HomeMy WebLinkAboutD91 Chem Hyg Aug10 (4) (3)
CONTENTS
1. PURPOSE
2. SCOPE AND APPLICABILITY
3. RESPONSIBILITIES
4. INSTRUCTIONS
5. RECORDS
6. DEFINITIONS
7. REFERENCES
8. APPENDICES
Appendix A – CHEMICAL INVENTORY FORM
Appendix B - CHEMICAL LABORATORY SAFETY
1. PRUDENT SAFETY PRACTICES FOR LABORATORY PERSONNEL
2. HANDLING AND USE OF CHEMICALS: LABORATORY OPERATIONS
3. HANDLING AND USE OF LABORATORY EQUIPMENT
4. CHEMICAL SPILLS
5. USE OF LABORATORY HOODS
6. LABORATORY USE OF GLOVES
Appendix C – DIRTY DOZEN OF LABORATORY CHEMICALS
PURPOSE
It is the policy of Idaho Falls School District #91 to provide a place of employment that is free from recognized hazards and to comply with all federal, state, and local laws and regulations
affecting the safety and health of its employees. This Chemical Hygiene Plan (CHP) helps ensure that Idaho Falls School District 91 employees and students who conduct activities in
District laboratories are protected from health hazards associated with laboratory use of hazardous chemicals (see def.). It provides uniform laboratory practices and protective measures
for use districtwide to minimize risks associated with laboratory chemical operations.
This procedure also helps maintain exposures to hazardous chemicals below established maximum safe levels, including the American Conference of Government Industrial Hygienists (ACGIH)
Threshold Limit Values (TLVs), Idaho General Safety and Health Standards, IDAPA 17, Title 10, Section 300, “Toxic and Hazardous Substances”, and the Occupational Safety and Health Administration
(OSHA) Permissible Exposure Limits (PELs). This procedure is issued in compliance with Idaho General Safety and Health Standards, IDAPA 17, Title 10, Section 111, “Laboratories and
Chemical Storage Safety Rules”.
SCOPE AND APPLICABILITY
This procedure applies to all Idaho Falls School District 91 laboratory use of chemicals and personnel using District 91 laboratories (such as visiting teachers, students, and personnel
from outside agencies). With respect to the laboratory use and potential exposure to laboratory chemicals, this procedure provides information regarding:
Chemical Hygiene Plan administration
Standard operating procedures
Chemical inventory, reference material, and labeling
Identification, evaluation, and control of chemical hazards
Engineering controls, PPE, and safe work practices
Carcinogens (see def.), reproductive toxins (see def.), and highly toxic chemicals (see def.) (particularly hazardous substances)
Employee information and training
Medical surveillance requirements
The occasional visitor to the district, such as a guest or sales person, is not included in the definition of employee and is therefore not subject to the CHP requirements.
Students pose a unique consideration; because students are not employees, provisions of the CHP do not formally cover them. However, safe chemical usage must be taught to all students
who use the lab. Students shall not be allowed to use District 91 laboratories unless a laboratory instructor directly supervises them. Students shall not be allowed to use District
laboratories outside of regular classes unless they first obtain permission from the school Chemical Hygiene Officer and are directly supervised during their work.
Appendix B provides policies and practices to standardize the methods used to promote chemical laboratory safety and minimize the risk associated with laboratory operations.
The Idaho General Safety and Health Standards, IDAPA 17, Title 10, Section 111, “Laboratories and Chemical Storage Safety Rules” is the primary basis document for chemical use in laboratory
operations. Other OSHA Standards, or certain parts of some OSHA Standards, may also be applicable to laboratory operations. The District Environmental Safety and Health Engineer should
be contacted regarding applicability questions.
RESPONSIBILITIES
The following personnel have key responsibilities for implementation of the Chemical Hygiene Plan:
Superintendent: The Superintendent is ultimately responsible for chemical hygiene within Idaho Falls School District #91 and, along with other administrators, provides continuing support
for the district-wide chemical hygiene program.
Environmental Safety and Health Engineer: The Environmental Safety and Health (ES&H) Engineer is responsible for coordinating the implementation and ongoing compliance with the CHP,
reviewing the CHP annually and updating as needed, coordinating safety inspections and conducting training on the chemical hygiene program.
Principal: The Principal is responsible for the chemical hygiene program at his or her school. The Principal appoints a Chemical Hygiene Officer for the school, and monitors, supports
and ensures school employees’ compliance with the CHP.
Chemical Hygiene Officer: The Chemical Hygiene Officer (CHO) is designated by the Principal to act as the point of contact for the school. The CHO is generally the head of the science
department for the school. The CHO works with the Laboratory Instructors and the ES&H Engineer to ensure the chemical
inventory is current, MSDS’ are available, and that student laboratory safety training and laboratory safety inspections are completed and documented.
Laboratory Instructor: The Laboratory Instructor is responsible for laboratory operations in his or her particular lab. The Laboratory Instructor is the person most familiar with activities
in their assigned laboratory, and works with the Principal, CHO and ES&H personnel to ensure the laboratory is operated in accordance with the CHP. It is the Laboratory Instructor’s
responsibility to conduct and document student laboratory training and laboratory inspections to ensure safe and compliant use of chemicals and laboratory equipment.
INSTRUCTIONS
Chemical Hygiene Plan Administration
Principal: Appoint a qualified individual to act as Chemical Hygiene Officer (CHO) for the entire school.
Identify individual Laboratory Instructors for each laboratory in the school. The instructors should be someone very familiar with the activities in the assigned laboratory, such as
the laboratory instructor.
Notify the Environmental Safety and Health (ES&H) Engineer of the names of the assigned CHO and Laboratory Instructors and the laboratories for which they are responsible.
Ensure personnel working in a laboratory are knowledgeable of specific hazards in the laboratory and have appropriate technical skill to perform the assigned work.
Ensure that personnel assigned to laboratories operating under this procedure have read this procedure.
NOTE: A copy of the CHP is available on the ES&H website (under construction).
Ensure personnel working in a laboratory are knowledgeable of specific hazards in the laboratory and have appropriate technical skill to perform the assigned work.
Ensure laboratory environment and work behaviors are safe.
Notify the employee and ES&H Engineer of any suspected employee overexposures to a hazardous chemical (see def.) and any work-related injuries or illnesses (suspected or actual).
Chemical Hygiene Officer: Serve as the primary contact in your school for ES&H, Principal and the laboratory instructors.
Ensure annual review of chemical inventory has been completed by each lab instructor and submit final inventories to ES&H Engineer using form in Appendix A.
Work with laboratory instructor to ensure all chemicals associated with the curriculum are reassigned or disposed prior to changes in curriculum or transfer or termination of an individual
involved in teaching in that location.
Laboratory Instructor: Serve as the primary contact in your laboratory for ES&H and the CHO.
Inspect the laboratory at the beginning of each school year using the Idaho Division of Building Safety Laboratory Checklist, located on the ES&H webpage.
Post the following emergency telephone numbers in an easily seen location: Fire Department, Physician or Hospital Emergency Room, Poison Control Center, Police, and Rescue.
Insure the laboratory has a spill kit that is adequately equipped for the chemicals used in the laboratory.
Check eye washes and safety showers at the beginning of each semester/trimester to insure they are functional. If a device is not functioning properly, submit a work order to have it
repaired.
If the laboratory is equipped with a fume hood, check the hood to ensure it is operating under negative pressure at the beginning of each semester/trimester. If the hood is not functioning
properly, submit a work order to have it repaired.
Maintain familiarity with all activities in the laboratory, including status of experiments and emergency shutdown procedures for both attended and unattended experiments.
Ensure that all operations within a laboratory are controlled such that potential incompatibilities have been mitigated.
Plan and conduct each activity in accordance with applicable experiment instructions.
Demonstrate good personal chemical hygiene habits (see Appendix B).
Ensure chemicals are kept in a locked storage location not accessible to students when not being used.
Know the hazards of chemicals used within the laboratories.
Work with CHO on conducting annual review of chemical inventory.
Conduct laboratory activities in a manner that promotes the safety of all employees and students working in the laboratory.
Report all suspected or actual work-related injuries, illnesses, and suspected over exposure to hazardous agents to the CHO, ES&H Engineer, and Principal.
Environmental Safety and Health Engineer: Work with school administration, the CHO and Laboratory Instructors to develop and implement appropriate chemical hygiene policies and practices.
Serve as a technical resource to assist school administration and employees in carrying out their responsibilities identified in the CHP.
Assist school administration, the CHO and Laboratory Instructors, as requested, in conducting self-assessments of their laboratories.
Maintain knowledge of the current regulatory requirements concerning regulated hazardous chemicals.
Review and evaluate the effectiveness of the CHP at least annually and update it as necessary.
Standard Operating Procedures
Environmental Safety and Health Engineer: Refer to the following regulatory standards for chemical-specific information, as needed:
NOTE: In addition to requirements specified Idaho General Safety and Health Standards, IDAPA 17, Title 10, Section 111, “Laboratories and Chemical Storage Safety Rules” applicable requirements
of District procedures or other regulatory standards are (1) exposure limits, (2) provisions to prevent eye and skin contact, (3) exposure monitoring (if employee exposures routinely
exceed the action level (see definition)), and (4) medical surveillance (if employee exposures routinely exceed the action level).
29 CFR 1910, Subpart Z, Toxic and Hazardous Substances
American Conference of Governmental Industrial Hygienists Threshold Limit Values for Chemical Substances and Biological Exposure Indices
Chemical Inventory, Reference Material, and Labeling
Chemical Inventory
Idaho Falls School District 91 uses the Flynn Scientific chemical management and storage system to ensure compliant and compatible storage of laboratory chemicals. Specific labeling
and storage information can be found in any Flynn Scientific catalog. If a chemical cannot be found in the Flynn catalog, please contact the ES&H Engineer for assistance with storage
requirements.
Laboratory Instructors: Ensure chemicals are labeled, managed and stored per Flynn Scientific or the ES&H Engineer’s recommendations.
Ensure all hazardous agents are listed on the Chemical Inventory using the form in Appendix A. An Excel version of this form is available for downloading on the ES&H Webpage.
Submit additions and/or deletions to the inventory to the CHO within two weeks of purchasing or disposing of a chemical.
Review and update Chemical Inventory at least annually to ensure it correctly reflects the chemicals and quantities on hand and submit marked up copy to CHO.
Chemical Hygiene Officer: Maintain accurate Chemical Inventory for the school.
Update the school’s chemical inventory within two weeks of receiving notification on additions and/or deletions from Lab Instructor.
Review and update the school’s Chemical Inventory at least annually to ensure it correctly reflects chemical types and quantities and submit revised inventory to the ES&H Engineer.
Chemical and Waste Disposal
Laboratory Instructors: While performing your annual inventory update, identify chemicals that are no longer used for the curriculum, have expired, or do not have an identified owner.
For chemicals you would like disposed, write “dispose” in the Comments column and submit Inventory form to the CHO.
For laboratory waste you would like to disposed, label the waste with a description of the contents, including concentrations of chemicals and contact the ES&H Engineer
Chemical Hygiene Officer: Submit a list of items needing to be disposed at your school to the ES&H Engineer.
Reference Material
Laboratory Instructor: Obtain and make accessible suitable reference material including, but not limited to, Material Safety Data Sheets (MSDSs) (see def.) for each hazardous agent
listed on the inventory.
MSDS’ for most laboratory chemicals can be found on the Flynn Scientific MSDS CS located in each laboratory binder or at http://www.flinnsci.com/search_MSDS.asp. If unavailable from
these sources, obtain the MSDS from the manufacturer.
Educate employees and students on how to obtain MSDSs.
Ensure employees do not use chemicals for which an MSDS is not available.
Obtain hazard information from the MSDS or other reference material for each chemical used and contact the Laboratory Instructor, ES&H Engineer, and/or CHO if questions arise.
Labeling
Laboratory Instructor: Ensure all chemicals used in your lab are properly labeled.
Label secondary storage or dispensing containers of chemicals with the name and concentration of the constituent(s) so personnel can:
Identify contents and associated hazards
Locate the applicable MSDS or reference material
NOTE 1: The preferred method of identifying contents is writing the entire chemical name(s). Appropriate abbreviations are acceptable.
NOTE2: Specific hazards, including, but not limited to, carcinogens, reproductive toxins, and highly toxic agents, should be noted in the labeling of secondary containers, especially
when stock solutions are prepared that will be stored/handled in the laboratory for extended periods of time. This is helpful in limiting storage and handling of particularly hazardous
substances to designated areas, as well as providing heightened awareness regarding the hazards to employees that are handling these chemicals.
Mark or label in-process reaction vessels in laboratories, laboratory glassware, samples of unknowns pending analysis, or experiments and analyses in process, as necessary to facilitate
identification of the contents.
Mark or label waste containers to show the type of waste that can be safely deposited.
Identification, Evaluation, and Control of Hazards
Laboratory Instructors: Identify and evaluate potential exposures to hazardous chemicals during laboratory operations.
Provide the CHO and the ES&H Engineer with a description of work activities and chemicals used.
Environmental Safety and Health Engineer: Provide input regarding potential chemical hazards.
Implement any necessary control measures to reduce employee exposure.
Periodically check the implementation and effectiveness of controls.
Engineering Controls, Personal Protective Equipment, and Safe Work Practices
Environmental Safety and Health Engineer: Assist School with determining engineering controls as appropriate to eliminate or minimize exposure to employees.
NOTE: Recommended engineering controls include: (1) providing adequate air changes in the laboratory (typically this would be 4-12 air changes per hour), (2) directing air into the laboratory
from non-laboratory areas and out to the exterior of the building, (3) substituting less hazardous chemicals for hazardous chemicals, and (5) isolating users from exposure to chemicals.
Laboratory Instructor: Ensure students or other employees use laboratory hoods or other specialized ventilation systems when required for protection from hazardous chemicals.
Ensure use of personal protective equipment as outlined in laboratory procedures
Refer to Appendix B regarding safe work practices in laboratories.
Carcinogens, Reproductive Toxins, and Highly Toxic Chemicals (Particularly Hazardous Substances)
It is the policy of Idaho Falls School District #91 to limit the usage of particularly hazardous substances through substitution with less hazardous substances. Particularly hazardous
substances include carcinogens, reproductive toxins and highly toxic agents. No particularly hazardous substances are allowed in District
laboratories without written approval of the Superintendent in concert with the recommendations of the ES&H Engineer.
Laboratory Instructor: Work with CHO and ES&H Engineer to identify designated areas for the handling of carcinogens, reproductive toxins, and highly toxic chemicals if needed.
NOTE: The designated area may be the entire laboratory or, at the Laboratory Instructor’s discretion, a limited area of the laboratory. The designated area should be identified by an
appropriate sign, but may be identified in other ways (e.g., within a laboratory document) for special circumstances.
IF the ES&H Engineer has determined there is a significant potential for employee exposure to carcinogens at or above the action level (per applicable OSHA standards),
THEN implement a carcinogen control program.
Enforce the required use of special containment devices, special waste disposal methods, and personnel decontamination, including washing, as necessary.
Ensure that spills are cleaned up per Appendix A, Section 4, “Chemical Spills”.
Use designated areas to handle particularly hazardous substances.
Use containment devices (e.g., laboratory hoods, glove boxes) to handle particularly hazardous substances whenever feasible.
Wear appropriate personal protective equipment to help prevent skin contact, absorption, or ingestion of particularly hazardous substances.
Wash upon completion of any work with hazardous substances.
Employee Information and Training
Principal: Upon initial assignment, ensure adequate job-specific training and information sessions are provided to all employees. Provide refresher courses, as necessary.
Ensure all Laboratory Instructors and other employees handling chemicals read and understand the Chemical Hygiene Plan.
Chemical Hygiene Officer: Provide training on general categories of chemical hazards, as needed, as applicable to the work activities.
Provide supplemental information and training, as needed, for those chemicals (including those produced in the laboratory) and experiments with unique hazards not sufficiently addressed
by categorical, job-specific training. This training must include:
Methods and observations used to detect the presence of hazardous agents (i.e., monitoring, appearance, or odor)
Physical and health hazards of the hazardous agents
Measures employees can take to protect themselves from these hazards, including specific procedures implemented, appropriate work practices, emergency procedures, and PPE.
Laboratory Instructors: Ensure all students have received training on chemical and laboratory safety and document this training with the CHO. This training shall be held at the beginning
of each semester/trimester and whenever practice demonstrates a need.
Environmental Safety and Health Engineer: Provide support and assistance with training as requested by the Principal, CHO, or Laboratory Instructors.
Medical Surveillance Requirements
Principal, Chemical Hygiene Officer, Laboratory Instructors: Report occurrences, including actual or suspected exposures to hazardous chemicals to the ES&H Engineer.
Principal: Ensure employees covered under the Chemical Hygiene Plan are given the opportunity to receive medical attention (including follow-up examinations deemed necessary by the physician)
under the following conditions:
A. Whenever an employee develops signs or symptoms associated with a hazardous chemical to which the employee may have been exposed in the laboratory
B. Whenever an event such as a spill, leak, explosion, or other occurrence takes place in the work area resulting in the likelihood of a hazardous exposure to employee(s)
C. If routinely exposed above the action level as required by a State or OSHA standard.
Make available, when requested, all relevant MSDSs and any other available toxicological data to the medical facility whenever an employee reports to or is transported to one, due to
a chemical exposure.
Make available, when requested, all relevant MSDSs and any other available toxicological data to the medical facility whenever an employee reports to or is transported to one, due to
a chemical exposure.
When medical consultations and/or examinations are provided as required by this procedure, provide medical personnel with the following information (as applicable):
The identity of the hazardous chemical(s) to which the employee may have been exposed
A description of the conditions under which the exposure occurred including quantitative exposure data, if available, and
A description of the signs and symptoms of exposure that the employee is experiencing, if any.
Environmental Safety and Health Engineer: Assist the Principal in gathering information.
RECORDS
None
DEFINITIONS
Action Level. A concentration designated in , IDAPA 17, Title 10, Section 300 or 29 CFR Part 1910 for a specific substance, calculated as an 8-hour, time-weighted average, which initiates
certain required activities such as exposure monitoring and medical surveillance. If 29 CFR Part 1910 does not designate an action level, monitoring and surveillance shall be initiated
when the concentration is one-half the PEL or TLV.
Boiling Point. The temperature at which the vapor of the liquid is in equilibrium with atmospheric pressure (defined at standard atmospheric pressure of 760 mm of mercury).
Carcinogen. Carcinogens regulated by OSHA; or listed as an IARC-1, -2A, or -2B; NTP -1 or -2; ACGIH A1 or A2 carcinogen; or a mixture containing at least 0.1% by weight or volume of
any of these (see Carcinogen definition, MCP-2703).
Corrosive Chemical. The action of the chemical will result in an immediate, acute deterioration or destruction of tissue or other materials.
Cryogenic Fluid. A substance that exists only in the vapor phase above minus 73(C at one atmosphere pressure and that is handled, stored, and used in the liquid phase at temperatures
at or below minus 73(C while at any pressure.
Flash Point. The minimum temperature at which a liquid gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid.
Hazardous Chemical. A chemical for which there is statistically significant evidence based on at least one study conducted in accordance with established scientific principles that
acute or chronic health effects may occur in exposed employees. Chemicals that are carcinogens, toxic or highly toxic agents, reproductive toxins, irritants, corrosives, sensitizers,
hepatotoxins, nephrotoxins, neurotoxins, agents which act on the hematopoietic systems, or agents that damage the lungs, skin, eyes or mucous membranes are considered hazardous chemicals.
Highly Toxic Chemical. A chemical falling within any of the following categories:
A chemical that has a median lethal dose (LD50) of 50 milligrams or less per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.
A chemical that has a median lethal dose (LD50) of 200 milligrams or less per kilogram of body weight when administered by continuous contact for 24 hours
(or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between 2 and 3 kilograms each.
A chemical that has a median lethal concentration (LC50) in air of 200 parts per million by volume or less of gas or vapor, or 2 milligrams per liter or less of mist, fume, or dust,
when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each.
NOTE: Occasional cases are found in the toxicology literature when the animal data fall outside the categories listed above, yet limited evidence indicates a higher level of toxicity
to humans. Whenever the data show a degree of human acute toxicity falling into one of the categories listed above, this chemical is considered highly toxic based on the human evidence,
regardless of the animal data.
Ignition Temperature. The minimum temperature that will initiate a self-sustained combustion independent of the heat source.
Laboratory. Laboratory means a facility where the “Laboratory Use of Hazardous Chemical” occurs. It is a workplace where relatively small quantities of hazardous chemicals are used
on a non-production basis.
Laboratory Use of Hazardous Chemicals. Handling or use of hazardous chemicals in which all of the following conditions are met:
Chemical manipulations are carried out on a laboratory scale in which the containers used for reactions, transfers, and other handling of substances are designed to be easily and safely
manipulated by one person. Laboratory scale excludes those work places whose function is to produce commercial quantities of materials.
Multiple chemical procedures or chemicals are used.
The procedures involved are not part of a production process, nor in any way simulate a production process.
Protective laboratory practices and equipment are available and in common use to minimize the potential for employee exposure to hazardous chemicals.
Lower Explosion Limit. The minimum concentration of a combustible vapor, by volume percent in air, below which a flame will not be propagated in the presence of an ignition source.
Material Safety Data Sheet. Written or printed material concerning a hazardous agent, prepared in accordance with 29 CFR 1910.1200. An MSDS for any chemical, or product can be provided
by the manufacturer.
Readily Accessible. Available to employees without barriers, and the employee must know how to access an MSDS without asking for help.
Reproductive Toxin. A chemical that affects the reproductive capabilities including chromosomal damages (mutagens) and effects on the fetus (teratogens).
Upper Explosion Limit. The maximum concentration of a combustible vapor, by volume percent in air, above which a flame will not be propagated in the presence of an ignition source.
REFERENCES
IDAPA 17, Title 10, Section 111, Laboratories and Chemical Storage Safety Rules
IDAPA 17, Title 10, Section 300, Toxic and Hazardous Substances
29 CFR 1910.1450, Occupational Exposure to Hazardous Chemicals in Laboratories
29 CFR 1910.1200, Hazard Communication
CRC Handbook of Laboratory Safety, Third Edition (1990)
Prudent Practices for Handling Hazardous Chemicals in Laboratories, National Research Council, 1981
Practice for Occupational and Educational Eye and Face Protection, American National Standards Institute, ANSI 287.1-1989
Fire Protection for Laboratories Using Chemicals, National Fire Protection Association, NFPA 45, 1996
APPENDICES
Appendix A, Chemical Inventory Form
Appendix B, Chemical Laboratory Safety
Appendix C, Dirty Dozen Laboratory Chemicals
Appendix A – Chemical Inventory Form
Material Name/Constituents
Flynn Storage Category
Physical Form
Cont. Type
Cont. Size
Amount Remaining
Number of Cont.
Owner
Lab
Comments
Appendix B - CHEMICAL LABORATORY SAFETY
PRUDENT SAFETY PRACTICES FOR LABORATORY PERSONNEL
Plan the work carefully regardless of the size of the task.
Ensure that the right equipment is available, is in good condition, and is used for its designed purpose.
Read and understand the MSDS before using any new chemical.
Be aware of proper waste disposal methods for the chemicals you are handling.
Mouth suction to pipet chemicals or to start a siphon shall NOT be permitted for any reason; a pipetter, pipet bulb, or aspirator shall be used.
Ensure that all systems are assembled in a stable and solid manner.
Do not work alone with chemicals.
Work with particularly hazardous substances in an approved fume hood, glove box, or other control device.
Use an explosion shield or other protective enclosure if there is a possibility of a violent reaction.
Practical jokes or other behavior that might distract, startle or confuse another person can be dangerous and must be avoided.
If you leave an operation unattended for any period of time, leave the laboratory lights on, post a sign, and take necessary precautions for the event of a failure of a utility service.
An unattended laboratory must be locked any time chemicals are out of loced cabinets or storerooms.
Handle chemicals carefully at all times, use appropriate containers and carrying devices, and close containers after use.
Work safely and deliberately following approved procedures.
Follow good housekeeping practices and be careful to properly store chemicals not in use.
Ensure that you are familiar with and follow emergency procedures and know the location of safety showers, panic buttons, etc.
Do not block egress from the work area.
Use required protective equipment, wear appropriate clothing, and confine long hair.
Eating, drinking, smoking, and chewing are prohibited in laboratories except in approved areas.
Wash any portion of the body that has contacted chemicals.
Remove PPE and dispose of appropriately to prevent contamination outside of laboratories, designated areas, or other chemical handling areas.
Seek guidance from your Laboratory Instructor, or safety professional for any unresolved safety issues.
Minimize all chemical exposures. General precautions include avoiding all skin contact, wearing appropriate PPE (safety glasses and gloves as a general precaution), and working in adequately
ventilated areas.
Avoid underestimation of risk. Minimize exposure even for chemicals of no known significant hazard. Assume any mixture will be more hazardous than its most toxic component. Assume
all substances of unknown toxicity are toxic.
HANDLING AND USE OF CHEMICALS: LABORATORY OPERATIONS
Corrosive Chemicals (see def.)
The categories of corrosive chemicals are broad, and include acids and bases, dehydrating agents, and oxidizing agents. They are commonly considered to be corrosive materials since
their actions can result in an immediate, acute, erosive effect on tissue and other material.
The following is specific information and safe practices to be used when dealing with these categories of corrosives.
Acids—Concentrated strong acid can cause severe and painful burns. Generally, inorganic acids are more dangerous than organic acids, although the latter can cause deep-seated burns
on extended contact with the skin. Weaker acids such as hydrofluoric (HF) and glacial acetic acid are also very corrosive and very penetrating. Dilute HF is one of the most insidious
acids because several hours
may pass after the HF has penetrated the skin before the affected person is aware of the exposure.
Alkalis—Alkali metal hydroxides are very dangerous when allowed to come into contact with tissue. Contact with the skin may be less painful than a comparable exposure to acid. Damage
may extend to greater depths as a result of the lesser pain because the injured person may not be as aware of the seriousness of the incident.
Nonmetal chlorides—Compounds such as phosphorous trichloride and corresponding bromides react violently with water.
Dehydrating agents—Strong dehydrating agents, such as sulfuric acid, sodium hydroxide, phosphorus pentoxide, calcium oxide, and glacial acetic acid, can cause severe burns to the eyes
because of their strong affinity for water. When they are added to water too rapidly, violent heat-release reactions, accompanied by spattering, can occur.
Halogens—Halogens are corrosive on contact with the skin, eyes, and the linings of the respiratory system. Halogens can also be toxic when inhaled.
High energy oxidizers—Oxidizing agents, such as chlorates, perchlorates, peroxides, nitric acid, nitrites, and permanganates, represent a significant hazard in the laboratory because
of their propensity (under certain conditions) to undergo vigorous reactions when they come into contact with easily oxidized materials such as metal powders and organic materials (such
as wood, paper, and other organic compounds). Elements from group 7B of the periodic table (fluorine, chlorine, bromine) react similarly to oxygen and are classified as oxidizing agents
as well. Table 1 is a list of common, powerful, oxidizing agents.
Table 1. Common High Energy Oxidizing Agents.
Ammonium perchlorate (NH4ClO4)
Ammonium permanganate (NH4MnO4)
Barium peroxide (Ba2O2)
Bromine (Br2)
Calcium chlorate (Ca[ClO3]22H2O)
Calcium hypochlorite (Ca[ClO]2)
Chlorine (Cl2)
Chlorine trifluoride (ClF3)
Chromium anhydride or chromic acid (CrO3)
Dibenzoyl peroxide ([C6H5CO]2O2)
Dinitrogen tetroxide (in equilibrium with nitrogen dioxide) (N2O4;NO2)
Fluorine (F2)
Hydrogen peroxide (H2O2)
Magnesium perchlorate (Mg[ClO4]2)
Nitric acid (HNO3)
Nitrogen trioxide (N2O3)
Perchloric acid (HClO4)
Potassium bromate (KBrO3)
Potassium chlorate (KClO3)
Potassium perchlorate (KClO4)
Potassium peroxide (K2O2)
Propyl nitrate (normal) (CH3[CH2]2NO2)
Sodium chlorate (NaClO3)
Sodium chlorite (NaClO2)
Sodium perchlorate (NaClO4)
Sodium peroxide (Na2O2)
Ammonium perchlorate (NH4ClO4)
Ammonium permanganate (NH4MnO4)
Barium peroxide (Ba2O2)
Bromine (Br2)
Calcium chlorate (Ca[ClO3]22H2O)
Calcium hypochlorite (Ca[ClO]2)
Chlorine (Cl2)
Chlorine trifluoride (ClF3)
Chromium anhydride or chromic acid (CrO3)
Dibenzoyl peroxide ([C6H5CO]2O2)
Dinitrogen tetroxide (in equilibrium with nitrogen dioxide) (N2O4;NO2)
Fluorine (F2)
Hydrogen peroxide (H2O2)
Magnesium perchlorate (Mg[ClO4]2)
Nitric acid (HNO3)
Nitrogen trioxide (N2O3)
Perchloric acid (HClO4)
Potassium bromate (KBrO3)
Potassium chlorate (KClO3)
Potassium perchlorate (KClO4)
Potassium peroxide (K2O2)
Propyl nitrate (normal) (CH3[CH2]2NO2)
Sodium chlorate (NaClO3)
Sodium chlorite (NaClO2)
Sodium perchlorate (NaClO4)
Sodium peroxide (Na2O2)
Perform work with these corrosive materials in a fume hood or other control apparatus appropriate for the material and quantity being used. Consult the MSDS for information concerning
the PEL and TLV for the particular corrosive chemical being used.
Use personal protective equipment (PPE) that is appropriate for the chemicals being used. Appropriate PPE will depend on several factors, including the type of corrosive, the amount
and concentration being handled, and the type of handling. However, for activities that present a risk of splashing corrosives into one’s eyes or onto one’s skin, PPE should include
chemical goggles and neoprene or butyl rubber gloves. Severe exposures may also require laboratory aprons and full face shields. In certain situations it may be sufficient to wear
safety glasses and nitrile gloves (e.g., when work process creates very little risk of splashing, when working with sufficiently small volumes, when working in a fume hood with the
sash down, or if working with sufficiently dilute solutions). Appropriate PPE (eye protection, gloves, etc.) will be specified in laboratory procedures. Consult the MSDS, glove selection
literature, or a safety and health professional when choosing the proper gloves for each corrosive chemical. Corrosive chemicals should only be used in laboratories that are equipped
with both a safety shower and an eyewash fountain. Locate this safety equipment prior to chemical use.
When available, corrosive chemicals should be purchased in containers coated with a protective plastic film so in the event they are dropped, the probable result will be a leak through
the film instead of a potentially dangerous splashing of the chemical. Keep the container sizes and quantities on hand as small as possible, consistent with the rate of use.
When using strong acids, an appropriate spill kit shall be readily available for neutralizing small spills.
When mixing concentrated acid with water, it is important that the acid be added to the water. Addition of water to a concentrated acid solution results in the generation of a significant
amount of heat that often causes the acid to splatter or breaks the glass container. Strong solutions of NaOH or KOH, when diluted with water, will also generate a significant quantity
of heat.
Solvents
The hazards associated with solvents originate in their ability to easily form vapors (and sometimes be readily absorbed through intact skin). These vapors contribute to the increased
likelihood of inhaling the solvent or, if the solvent is flammable, initiating a fire. Absorption through intact skin increases employee overall exposure.
The potential of inhaling toxic vapors from solvents can be minimized by limiting the quantity of solvents used and working with the solvents in an approved laboratory hood. Some solvents
can also be a skin hazard due to their ability to defat the protective oils from the skin, thereby increasing the potential for dermatitis. The potential for dermatitis can be minimized
by engineering controls, proper glove selection, and good hygiene practices. Consult the MSDS, glove selection literature, and/or a safety and health professional when choosing the
proper gloves for each solvent.
The potential fire hazard of flammable solvents is determined by the solvent’s boiling point and flash point. Definitions for both of these properties are provided in Section 6 of this
procedure. Three other important factors are the ignition (autoignition) temperature, the lower explosion (or flammable) limit (LEL) (see def.), and the upper explosion (or flammable)
limit (UEL) (see def.). Definitions for these terms are also provided in Section 6, Definitions.
The National Fire Protection Association (NFPA) uses boiling point and flash point properties to assign flammable liquids to various classes.
When using solvents in the laboratory, consult the MSDS or other reference data before using the solvents to determine if it is a flammable or combustible liquid.
For a fire to occur involving a flammable liquid, three conditions must be met: (1) the concentration of the vapor must be between the upper and lower flammable limits, (2) an oxidizing
material must be available (usually the air in the room will suffice), and (3) a source of ignition must be present.
The following measures are recommended to mitigate the three factors required to cause a fire:
Perform work with flammable solvents in an appropriate fume hood whenever possible. Using a fume hood helps prevent the buildup of vapors. Small quantities (<200 ml for class 1A and
1B and <500 ml for class 1C flammable liquids) of solvents may be used outside the hood provided adequate ventilation is present.
Keep the amount of flammable solvents in use to the absolute minimum required to complete the work being performed. Store all flammable solvents not in use in an approved storage cabinet
or storage area.
Eliminate possible ignition sources that could cause a fire to start. Open flames are an obvious source of ignition. Hidden ignition sources, such as sparks from electric motors, light
switches, and other electrical equipment, are also common in laboratory operations. Hot surfaces are another potential ignition source. Some flammable liquids have ignition temperatures
(see def.) low enough to be ignited by coming into contact with the surface of a light bulb. Review the data available for the solvents that will be used and survey the laboratory
to identify and eliminate possible ignition sources.
Reactive Metals
Lithium, potassium, and sodium are three metals that react vigorously with moisture. Other metals, such as magnesium, also react when they are in a dispersed form, like fine shavings
or powdered. In the reaction with water, the corresponding hydroxide is formed along with flammable hydrogen gas.
The chemical hazards of lithium, potassium, and sodium are similar. All three form explosive mixtures with a number of halogenated hydrocarbons. All three react vigorously or explosively
with some metal halides, although potassium is significantly worse in this respect, and the reaction of all three in forming a mercury amalgam is violent. Also, they all react vigorously
with oxidizing materials. Potassium will form the peroxide and superoxide when stored under oil at room temperature and may explode violently when cut or handled. Sodium reacts explosively
with aqueous solutions of sulfuric and hydrochloric acids.
Store lithium and sodium under mineral oil or other hydrocarbon liquids that are free of oxygen and moisture or in an inert (argon for lithium, argon or nitrogen for sodium) atmosphere.
Store potassium under dry xylene.
Since these three metals all react vigorously with moisture, avoid skin and eye contact that could result in burns from the severe heat and direct action of the hydroxides. Always use
these materials in an appropriate hood or glove box. As a minimum, use appropriate gloves and eye protection as personal protective equipment. Lithium will react with pure nitrogen.
Research involving reactive metals shall be evaluated to determine the appropriate size and type of Class D fire extinguisher to be available within the laboratory.
Finely Divided Metal Powders
Unstable and very rapid reactions can occur with some finely divided metals when presented with sources of oxygen and ignition. When particle sizes become very small (very high specific
surface areas), some metals become pyrophoric (capable of igniting spontaneously in air at ambient temperatures).
In all cases, three simultaneous events must occur to produce a powder metal explosion:
Dust cloud of finely divided metal
Source of oxygen
Ignition source
During measuring, pouring, and mixing operations, the potential for generating a dust cloud of fine metal particles is very high, almost unavoidable. For safety in these operations,
it is important to try to minimize the creation and duration of dust clouds, while denying the system oxygen and sources of ignition. Thermite mixtures are examples of energetic materials
which do not require any gaseous oxygen sources, because they contain at least one metal oxide. Once ignited, thermites can burn as easily in a vacuum or in an inert environment as
they can in air.
In many cases the most preventable of the three coincident events is the ignition source. Ignition sources fall into three additional groups, 1) obvious heat and spark sources, 2) mechanical
heat generators, and 3) self heating and static discharge. Electrostatic discharge can ignite some types of metal clouds, if grounding provisions are inadequate. Zirconium, magnesium,
and aluminum powders are among the most vulnerable to electrostatic ignition. Zirconium in particular is prone to generate static charges within dust clouds.
Among the more common members of this group of high dust explosion hazard metals are zirconium, magnesium, aluminum, lithium, and sodium. This group is characterized by low oxygen concentration
requirements (<3%), low energy required for ignition, ignition temperatures below 600oC, low powder concentrations needed, and high energy release after ignition.
Examples of common medium hazard metals are tin, zinc, iron, silicon, manganese, and copper. These metals require more oxygen (>10%), require more energy, higher ignition temperature
(300 to 800oC), have greater metals concentration hazard thresholds, and have lower energy release.
Cobalt, Lead, and Molybdenum are common examples of metals with a low dust explosion hazard. These metals have high ignition temperatures (>700oC) and require very high powder concentrations
before ignition occurs.
Guidelines for Metal Classes:
High Dust-Explosion Hazard Metal Powders
Powders in the high dust explosion hazard group having particle sizes less than 150m (or -100 sieve) should be treated with significant caution to avoid accidental ignition.
Use inert environments to the extent possible for loose powder handling. Because of the low oxygen concentrations required for ignition, storage and mixing containers should be evacuated
and refilled with argon or other inert gas approved by the Industrial Hygienist. As an alternative, loose powder handling may be performed in an argon filled glove box.
Avoid dust cloud formation, particularly when handling loose powders in air. Avoid powder agitation that would result in a fine dispersion of powder.
Ground sufficiently to avoid static discharge. As appropriate, ground all containers during measuring, mixing, and storage of powders. Laboratory personnel handling fine metal powders
shall be grounded by using wrist bands, grounding floor mats or other similar devices. For static grounding, continuity with ground (i.e., a finite resistance) needs to be demonstrated.
Each specific application needs to be evaluated by a Safety Engineer to ensure the appropriate mat or grounding devices are used.
Isolate powders from heat sources. Obvious heat sources, and mechanical friction heat (bearings, etc.) should be avoided. By using fairly small amounts, the self heating problem can
be avoided. It has been suggested that micro mechanical heating due to intense particle impact might be possible. Although this source of heating has not been substantiated, it would
be easily avoided through slower, smoother, less aggressive mixing practices.
Even with other precautions, accidental ignitions should be anticipated and personal protective measures should be used. For open handling of powders in air, fire resistant garments,
(such as welding smocks etc.) and full face protection are recommended. The use of fire retardant gloves is also recommended to the
extent reasonable. In operations that require fine measurements of small quantities of powders, use of such gloves may be prohibitive or may cause other hazards. For operations in
inert gas glove boxes, only normal laboratory clothing should be necessary.
The magnitude of the physical hazard caused by an accidental ignition increases as the quantity of the powder increases. When practical, isolate powders from one another and minimize
the stored quantities to avoid secondary ignitions. Make use of bulk storage away from personnel to reduce the potential hazard to personnel.
Mixing operations should be done only by bonded and grounded mechanical devices. Additionally, sufficient shielding protection shall be placed around the mixing device to limit collateral
damage to people and equipment if an accidental ignition occurs.
Medium Dust-Explosion Hazard Metal Powders
These materials may have different handling criteria due to the strong influence of the specific surface area of the metal powder and the various chemical interactions of metals in this
category. When in doubt, high hazard handling procedures are recommended. It should be remembered that a small change in specific surface area can cause an abrupt change in the hazard
associated with this group of metals.
Low Dust-Explosion Hazard Metal Powders
Alone, these powders offer little danger of hazardous ignition due to lack of sensitivity to electric discharge and high ignition temperatures. Grounding and other protective provisions
should not be required for this group of materials.
Thermites
Thermites contain a mixture of one or more powdered metals and one or more metal oxides. Consequently, thermites are a special subclass of the powdered metals concern. In most cases,
thermites are more difficult to ignite than the original powdered metals that they contain. However, once ignited, thermite mixtures contain an oxygen source in the form of metal oxide
powders. Consequently no gaseous oxygen source is needed for combustion. No type of fire extinguisher will be effective on burning thermites.
Thermites commonly contain one or more of the high hazard powdered metals. Consequently, thermites should be treated like the high hazard metals.
Compressed Gases
Safety issues of compressed gases range from the chemical properties of the gases to the physical integrity of the gas cylinders.
Idaho Falls School District 91 has added the following requirements or precautions:
Do not use copper tubing for acetylene or oxidizing gases such as oxygen.
Do not open acetylene cylinder valves more than one-half turn; open all other cylinder valves fully to prevent leakage around the valve stem.
Many gases are heavier than air, so they may collect in depressions or areas with little air movement and become a danger to unsuspecting persons.
Many gases do not have a distinctive odor or are not sufficiently irritating to warn of their presence. Some gases that do have an odor, such as hydrogen sulfide, desensitize the sense
of smell at levels that are dangerous.
Ensure adequate ventilation for systems involving toxic gases. If possible, set up the systems totally within a fume hood. Contact ES&H to evaluate the hood air flow with system in
place. Carefully leaktest all systems before introducing toxic materials into the system. Periodically test them from introduction, during, and after performing any maintenance or
modifications to the system that could affect its integrity.
Carcinogens
During laboratory experiments, it may become necessary to use a known or suspect carcinogenic material. Before using a carcinogen, evaluate the possibility of using a suitable substitute.
If a suitable alternative is not feasible or cannot be found, follow the requirements of Section 4.6 of the Chemical Hygiene Plan.
HANDLING AND USE OF LABORATORY EQUIPMENT
3.1 Sharps and Glass
SHARPS
Generally, sharps refers to items such as syringe needles, glass GC syringes, and other needles. A significant number of injuries from "sharps" occur in research labs each year. A high
percentage of these injuries are avoidable. Anyone who uses a sharp is personally responsible for its correct use and for its safe disposal. Consider the following:
Safe Use
Sharps should only be used when absolutely necessary.
Sharps must never be left lying where they are likely to cause injury to others.
Used “disposable” needles should not be re-sheathed after use.
If at all possible, dispose of needles immediately without recapping them.
If needles must be recapped, use the "one-hand" technique: (1) place cap on flat surface, then remove hand from cap, (2) with one hand, hold the syringe and use the needle to scoop up
the cap, and (3) when the cap covers the needle completely, use the other hand to secure the cap on the needle hub.
Disposal
All sharps must always be disposed of in the approved "sharps bins."
Non-contaminated broken glass should be placed in large cardboard containers for transport to and disposal in the trash dumpsters.
Do not bend or break the needle and do not remove a needle from the syringe by hand.
Syringes and needles should not be separated before disposal.
It is essential that sharps bins are not over-filled, as used needles protruding from the containers constitute a significant hazard.
Before the bins are removed to the collection point, they must be checked to ensure that the lid is securely attached to the base and that the flap has been securely closed.
Sharps must never be placed directly into autoclave bags used for biological waste, or into waste bins used for general waste items.
GLASS
Glass is involved in a high percentage of laboratory accidents. Glass reagent bottles may be dropped and shattered. Flasks may explode or implode due to pressure differential. Tubing
may break while being handled, causing cuts that can be severe. Glass systems may fail due to stress. Individuals may burn themselves handling hot beakers or flasks or while trying
to fabricate glass items. All glassware should be inspected for sharp edges and cracks prior to use and be repaired or removed, as appropriate.
Laboratory glassware shall never be used for beverage or food containers, even if properly marked. The risk of confusion and the potential for serious injury is far too great for this
to be an acceptable practice.
Virtually all glass laboratory containers should be made of borosilicate glass, except containers required for unusual applications that may require glass with different characteristics.
Glass containers or systems that may undergo especially demanding heat stress should be made of silica glass.
Spherical glass containers are stronger than glass items of comparable wall thickness that have different shapes. Larger items, especially if they are non-spherical, should be made with
heavy walls to withstand the pressures to which they might be exposed.
Tape glass containers or portions of glass equipment under pressure; if they implode or explode, the tape will minimize any flying shards of glass. Metal enclosures or screens will also
protect nearby personnel.
Cuts from mishandling glass tubing are common, especially while attempting to insert tubing into a rubber stopper, hose, or piece of plastic tubing. Unfired broken glass is usually extremely
sharp, and severe cuts may result if tubing breaks while attempting to force it through a stopper. To safely insert a piece of tubing (or a glass thermometer) into a hole, follow these
procedures:
A. The hole should not be too small. The hole should be large enough to just grip the tubing. If a new hole is to be cut in a stopper, the borer should be one size smaller than one
that will just barely slip over the tubing. The hole should be clean and regular. Lubrication of the borer helps cut a clean hole.
B. The edges of the glass tubing being inserted shall be fire polished. An unpolished edge will tend to dig into the sides of the stopper.
C. Lubricate the glass tubing with water, glycerol, stopcock grease, or other available lubricants compatible with the intended use.
D. Wrap a cloth around the glass. Either wrap the hand holding the stopper or hose with another cloth, such as a piece of toweling; or put on leather work gloves or stainless steel
wire mesh gloves.
E. Grasp the glass tubing at a point within 1 to 2 inches of the end to be inserted into the hole.
F. Push the end of the glass into the hole while exerting moderate pressure with a slight twisting motion. Do not attempt to push or twist too vigorously since this may lead to exerting
sufficient lateral force on the glass to break it.
It is also possible to get cut while deliberately breaking glass. To break a section of tubing, score a nick with a sharp file extending about a third of the way around the circumference,
preferably in a single smooth stroke. Multiple scribe marks will often lead to a jaggedly broken piece of tubing. To break the tubing, wrap a cloth around the tubing, place the thumbs
against the covered glass on the side opposite the cut, and exert pressure on the glass
3.2 Heating Baths
Heating baths are used to heat containers partially immersed in them and maintain containers at a stable temperature, on some occasions, for extended periods of time. Heating baths
shall be in durable, nonbreakable containers and set up with a firm support so avoid being tipped over. Do not place heating baths near either flammable or combustible material that,
if exposed to continuous heating over a sufficient period of time, could reach kindling temperatures. In other words, heating baths should not be used, unattended, for prolonged, continuous
use. Also, do not place them near sources of water (particularly deluge showers), since bath liquids can splatter violently from the container if water is sprayed into the hot bath.
Take care in selecting the most appropriate bath fluid for the task to be conducted. Extra care is needed for bath fluids that are flammable, such as mineral oil, glycerine, and paraffin.
Knowledge of the physical properties of each bath fluid will assist in determining the appropriate fluid needed to safely attain and maintain the desired temperature.
Appropriate gloves and/or tools should be used when inserting or removing material from hot baths.
3.3 Laboratory Ovens
Electrically heated ovens are found in many laboratories and can be a source for igniting flammable vapors. Many ovens exhaust potentially toxic and flammable vapors or fumes into the
laboratory since most are not equipped with local exhaust ventilation. In addition, these vapors or fumes can accumulate to dangerous levels within the oven. Therefore, do not use
laboratory ovens to heat any material from which a toxic vapor or fume would be expected to evolve unless provisions are made to properly exhaust the fumes. Consult an Industrial Hygienist
or fire protection engineer when it is determined that a laboratory oven must be vented to control potential personnel exposures.
Appropriate gloves and/or tools should be used when inserting or removing material from hot ovens.
3.4 Laboratory Refrigerators
Under no circumstance shall laboratory refrigerators or freezers containing chemicals and/or biological agents be used to store food or beverages. Laboratory refrigerators must be labeled
with a sign stating no food is allowed.
The confined space within refrigeration units permits accumulation of vapors from improperly sealed containers. This can allow flammable and toxic concentration to accumulate within
the refrigerator. Therefore, laboratory workers should ensure all containers stored in a refrigerator or freezer are tightly stoppered or sealed to prevent evaporation or spilling
of materials. Beakers, flasks, and bottles containing toxic or flammable chemicals sealed only with aluminum foil or plastic wrap are unacceptable for storage in a refrigerator. Care
should also be taken to ensure that chemicals within the container do not become over-pressurized which may cause the container to burst.
Flammable chemicals that must be stored at reduced temperatures shall be stored in refrigerator devices designed to be explosion-resistant.
CHEMICAL SPILLS
Personnel Safety
Personnel safety is paramount when cleaning up a chemical spill. If the spilled chemical has been inhaled or ingested, seek medical assistance immediately. If a potentially irritating
or corrosive chemical has contacted an employee's eyes, skin, or clothing, immediately remove contaminated clothing and wash the affected body part.
If the eyes or skin are exposed to corrosive chemicals, immediately rinse the skin or eyes for 15 minutes and seek medical attention.
If hydroflouric acid (HF) contacts the skin, HF acid burn gel (2.5% calcium gluconate in water-soluble gel) should be massaged into the skin after rinsing the area of the skin exposed
to HF acid for one minute.
Spill Assessment
CAUTION
If there is any doubt that the spill cannot be safely cleaned up, a conservative approach must be taken by summoning outside help.
If any of the following conditions exist that would prevent the laboratory personnel from safely mitigating the spill, outside help must be summoned:
The spilled chemical has come into contact with eyes, mouth, nasal cavity, or skin and requires immediate use of the eyewash or safety shower
The quantity (based on the toxicity, reactivity or flammability) of the spilled chemical has placed or will place the laboratory personnel in imminent danger
The laboratory personnel do not have the proper personal protective equipment (PPE) needed to safely clean up the spill
The size of the spill is larger than can be contained with any readily available adsorbents, neutralizing agent, spill pillows, or other containment material(s)
The spilled chemical is being, or is likely to be, released into an uncontrolled environment and cannot be controlled with readily available material
Equipment in the facility or laboratory cannot be controlled and may initiate a hazardous situation when contacted by the spilled material.
Notification
Upon initial discovery of a chemical spill, all personnel in the adjacent area must be warned of the chemical spilled, quantity, and hazard(s), if known. As appropriate, the area shall
be posted to warn others and avoid contamination. Notify both the Laboratory Instructor, CHO and ES&H Engineer as soon as possible.
Spills Not Requiring Outside Help (as indicated in Section 4.2, Spill Assessment)
Outside help must be summoned if conditions exist, as specified in spill assessment, Section 4.2 of this appendix. Outside help may be summoned by dialing 9-911. Help will also be
summoned if a fire alarm, a help-needed button, safety shower, or sprinkler system is activated. Further information is available in the emergency response plan for the respective
areas. Spills which reach the outside environment must be reported to the ES&H Engineer.
Upon notification, the response organization may request the following information:
Incident and location
Number of injured and type of injuries
Chemical(s) involved and quantity
Initial mitigative action taken
Accountability of employees near the incident
Name of a contact person familiar with the operation
Laboratory personnel present when the spill occurred
Special conditions that exist in the laboratory.
Spills Not Requiring Outside Help (as indicated in Section 4.2, Spill Assessment)
Notify the Laboratory Instructor and CHO of the spill.
Each area has appropriate materials (spill pillows, adsorbents, neutralizing agents, etc.) for cleaning up small spills. Gloves, eye and face protectors and other PPE is also available
to many operations. Personnel shall only use the available resources where the use and limitations of the resources are fully understood.
Disposal
Once the spill is under control, the ES&H Engineer shall be contacted for information on proper disposal of the chemical and contaminated materials used to clean up the spill.
USE OF LABORATORY HOODS
Fume hoods are required in laboratories per the International Fire Code based on the hazard ranking of the chemicals used:
When corrosive materials are dispensed or used, mechanical exhaust ventilation in accordance with section 2705.2.1.1 shall be provided (I.F.C. Section 3105.1.2)
Where gases, liquids or solids having a hazard ranking of 3 or 4 in accordance with NFPA 704 are dispensed or used, a mechanical exhaust ventilation shall be provided to capture gases,
fumes mists or vapors at the point of generation.. (I.F.C. 2705.2.1.1)
Exception: Gases, liquids or solids that can be demonstrated not to create harmful gases, fumes, mists or vapors.
In general, implementation of the following items is necessary only for those activities where the potential for airborne hazards exists. In some situations implementation of the following
items is not necessary, such as those that don’t use hazardous chemicals or generate hazardous air contaminants and equipment set-up.
Prior to using a laboratory hood, ensure the hood has negative pressure. If the hood is not working adequately, place a sign on the hood that it is inoperable submit a work order requesting
the hood be evaluated. No work involving hazardous chemicals can be performed in the hood until the evaluation is complete.
Equipment in the hood should not block air-flow to slots in the baffle. When placing experimental equipment within the hood that has the potential to affect the air flow characteristics
of the hood, the hood must be checked to ensure negative pressure is adequate.
While working within the hood, adjust the hood sash position to a point where manipulations within the hood are not restricted, but where the sash still provides a shield for the head
and upper body. Position the sash such that the openings are at or less than the maximum opening indicated on the notice sticker and/or arrow(s) applied to the hood. The sash should
be lowered when user is not manipulating material within the hood, unless conditions indicate otherwise.
If any airflow indicating device indicates the hood is not functioning properly, immediately place a sign on the hood that it is inoperable and submit a work order for repair. The Laboratory
Instructor is responsible for ensuring operation of the hood is discontinued until the hood is recertified for use.
Equipment that might be a source of emission (including in case of breakage) should not be placed closer than 6 inches from the plane of the hood face.
Large equipment should be elevated at least two inches above the base of the fume hood.
Recirculating laboratory hoods (ductless laboratory hoods that pass air from the hood interior through an adsorption or absorption filter and then discharge the air into the laboratory)
are not acceptable for use.
Do not place your face inside the hood. Keep hands out as much as possible.
Do not store chemicals in the hood.
Clean up spills immediately.
Periodically clean hood interior.
Avoid cross drafts and disruptive air currents in front of the fume hood.
Heat sources (burners, hot plates, etc.) inside a hood can increase the likelihood of contaminants escaping from inside the hood into the worker’s breathing zone.
LABORATORY USE OF GLOVES
Chemicals present many types and degrees of dermal hazards. They may be irritants, corrosives, sensitizers, or systemic toxins via cutaneous absorption. Some chemicals have “skin” designations
per the American Conference of Governmental Industrial Hygienists (ACGIH) or the Occupational Safety and Health Administration (OSHA). This designation means that cutaneous exposure
can contribute significantly to the overall exposure. This may also be true for other chemicals, even though they don’t have skin designations. Protecting one’s hands from exposure
is an important concern.
Hand protection from chemical exposure is a challenge because laboratory workers normally require a high level of manual dexterity as well as needing protection against a variety of
chemicals. In order to meet the manual dexterity requirements, thin gloves are desired. Unfortunately, only a few glove materials are available in thin styles.
The effectiveness of a specific glove in protecting a worker is a function of several factors, including:
Type of glove material
Thickness of glove material
Specific chemicals being used
Whether or not combinations of chemicals are being used
Duration of contact between the chemical and the glove
Generic glove effectiveness is defined by three parameters: (1) breakthrough time, (2) permeation rate, and (3) degradation. Breakthrough time is the time it takes a chemical to pass
through the glove material until it is first detected by an analytical instrument in a standardized test. The permeation rate is defined as the speed of movement of the chemical through
the protective material once it has broken through. Degradation is the change in physical properties of the glove material as a result of reactions with the chemical. All of these
parameters are important when choosing appropriate gloves.
In many cases, the skin itself provides a barrier against chemical absorption. However, several factors can reduce the effectiveness of the skin’s protection mechanisms, such as:
Washing hands with soap prior to exposure
Covering the hands, e.g., wearing gloves
Cuts or abrasions
Often, nitrile gloves have been recommended for use in the laboratory. It is a relatively effective glove material, with respect to those materials available in a thin style. Latex
is another type of glove material available in a thin style. However, neither nitrile nor latex provides an effective barrier against all classes of chemicals. It is important to
recognize this limitation because (1) skin contact can result in significant exposure and (2) workers may have a false sense of security. In spite of these issues, nitrile or latex
gloves are often recommended for the following reasons:
Small amounts of the chemicals are being handled
Contact with the chemical is not expected
A high level of manual dexterity is required
If thin nitrile or latex gloves are being used, and if a given chemical has a short breakthrough time with the specific glove type, then the gloves should be immediately removed and
the hands thoroughly rinsed if contact with the chemical does occur.
There are cases where certain glove types are required by OSHA standards. For example, OSHA requires “impervious” gloves for workers handling methylene chloride. The only glove material
impervious to methylene chloride is polyvinyl-alcohol (PVA).
Other circumstances may also warrant requiring specific glove types regardless of whether or not these glove materials are available in thin styles. For example, when handling chemicals
that are highly toxic via cutaneous absorption (e.g., dimethylmercury), it may be safer to use thicker impervious gloves while sacrificing some manual dexterity.
The following table provides some examples of available information regarding specific chemicals and appropriate glove use. First it indicates if a chemical has a skin designation per
ACGIH or OSHA. Next, it briefly describes the consequence of skin exposure. Finally, breakthrough times are indicated for both the preferred glove type and nitrile and latex gloves.
Note that glove thickness is an important factor when establishing breakthrough times. The breakthrough times listed are for moderately thick gloves, and would be shorter for thinner
gloves. Please note that the information in this table is only for generic comparison of glove materials with pure chemicals. It is not intended to provide specific guidance regarding
acceptable glove contact times.
Chemical
Skin Notation
Consequence of Skin Exposure
Preferred glove type / breakthrough time
Nitrile breakthrough time
Latex breakthrough time
Acetone
No
Irritation
Butyl rubber /
>8 hours
3 minutes
2.4 minutes
Dimethyl sulfoxide
No
Irritation, allergic reactions, blood disorders
Butyl rubber /
>8 hours
28.2 minutes
79.8 minutes
n-Hexane
Yes
Irritation, blisters
PVA / >8 hours
78.6 minutes
4.8 minutes
Methanol
Yes
Irritation, CNS effects
Butyl rubber /
>8 hours
10.8 minutes
1.8 minutes
Methylene chloride
No
Irritation, CNS disturbances, suspect carcinogen
PVA / >8 hours
1.8 minutes
<1 hour
Nitric acid (30-70%)
No
Yellowing of skin, irritation, pain, burns
Butyl rubber
(>8 hours)
Neoprene
(>4 hours)
5 minutes
<5 minutes
Toluene
Yes
Irritation
PVA / >8 hours
<5 minutes
0.6 minutes
NOTE: PVA will dissolve when in contact with aqueous solutions
Finally, workers must remember that exposure may not be limited to those times when a chemical is being directly handled. Chemicals can spread through various means, some inherent to
the chemical (e.g., vaporization) or physically by the worker him/herself. For example, by wearing contaminated gloves to write in lab notebooks, handle equipment, or open doors, clean
surfaces can become contaminated. This may result in unprotected exposures to the worker or other employees. Therefore, it is important to remove contaminated gloves in a defined
area. Employees must ensure that work practices
address preventing the spread of chemicals to those areas where employees may not be wearing the appropriate gloves.
Help in choosing gloves is available. Work control documentation should specify appropriate personal protective equipment, including gloves if they are required for performing certain
tasks. Contact your local industrial hygienist or the chemical hygiene officer if you have any questions.
Appendix C – Dirty Dozen of Laboratory Chemicals
Excerpted from the Science Safety Guide prepared by Mr. Richard Kay, Idaho Department of Education.
Metallic Potassium: The yellow substance encrusting your supply of potassium metal is a violent shock-sensitive explosive that can turn any laboratory into an inferno. Metallic potassium
reacts with moisture to form potassium hydroxide and hydrogen. This reaction evolves heat, which ignites the hydrogen and either burns—or if confined explodes. It is extremely difficult
to extinguish. Ignition can be spontaneous. Metal which has oxidized while in storage under oil may explode violently when handled or cut. Get rid of any supply of metallic potassium
you have in stock. Students should never be permitted to handle this substance.
Metallic Sodium: Reacts exothermally with the moisture of body of tissue surfaces causing both thermal and chemical burns. This substance decomposes moisture to evolve hydrogen and
heat. It is spontaneously flammable in air when heated. Get rid of your metallic sodium. Students should never be permitted to handle this substance.
White Phosphorous: White phosphorous creates severe burns when exposed to organic tissues. Reacts violently—Get rid of it. Never allow students to handle this material.
Phosphorous Trichloride, Fuming Sulphuric Acid, Fuming Nitric Acid, Iodine Chloride, Etc.: Dispose of these substances or contact the appropriate individuals for disposal.
Carbon Tetrachloride, Benzene, Chloroform, Chlorobenzene, Etc.: If you must keep these materials, store properly where fumes are not released into the classroom.
Mercury: Mercury is an extremely dangerous cumulative poison and it should be handled with great care. Mercury is difficult to handle and teachers should be aware of the dangers. Mercury
is readily absorbed via the respiratory tract, and since it easily spills and flows, great care should be exercised in handling this material. It is extremely important that mercury
spills be cleaned up as soon and as completely as possible. Chronic effects include severe neurotoxicity, as well as swelling of gums and excessive salivation. Alkyl mercury and phenyl
mercury compounds may be absorbed through the skin and the mercury alkyl mercury compounds may cause permanent brain damage. Both sets of compounds cause severe delayed skin burns.
Inorganic salts of mercury (for example mercuric chloride) may be extremely corrosive to the mucus membranes.
Picric Acid: Picric acid, properly known as trinitroethenol, is a substance which becomes highly explosive and unstable with age. This substance is no longer in common use, but
some laboratories may still have supplies on hand. Picric acid is very similar in structure to TNT and has the same explosive capabilities. A large enough quantity could take down
an entire building. In the event you have a supply on hand, do not touch it. Contact the appropriate explosive experts for removal and disposal.
Asbestos: In the event there is asbestos in your laboratory, students and staff members should be alerted to the potential health hazards of the fibers of asbestos. Worn or cracked
asbestos material that may release particle into the air might be found in apparatus of science laboratories of in the construction of various areas of older buildings where heating
and cooling pipes are insulated with asbestos. In all situations, the asbestos material should be handled or protected so as to avoid dusting the fragments into the air. Worn materials
should be discarded and replaced. Substitute non-asbestos materials whenever possible.
Carbon Disulfide: Forget the experiment on dissolving sulphur. A hot steam pipe can ignite carbon disulphide vapors. Get rid of any supply you might have in stock.
Ethel Ether: Ethel ether is a substance which decomposes with age to form highly-explosive peroxides. In addition, ethel ether fumes are highly explosive. In the event you must purchase
and use this solvent, purchase it in extremely small quantities (i.e., 250 ml) and dispose of any remaining at the end of the school year. Do not store.
Potassium Chlorate: An experiment on generating oxygen and testing its properties is much better conducted using hydrogen peroxide with MnO2 catalyst or sodium hypochlorite (bleach),
using cobalt chloride or cobalt nitrate solution as catalyst. If you must keep chlorates, perchlorates, or permanganates for some purpose, keep only small quantities in locked cabinets
away from the young explosive experts.
Hydrofluoric Acid: An extremely dangerous substance. It is extraordinarily corrosive to skin and mucus membranes, producing painful burns which are very slow to heal. If spilled on
the skin near the fingernails, the result is not only painful, but if may easily cause loss of the finger. The burn immediately works in its way to the bone. Hydrofluoric acid is not
suitable for use in student laboratories under any conditions. If you have a supply on hand, it should be disposed of immediately and not replaced.