LABORATORY AND FIELD SAFETY. Millie Tran and Sheryl Mansour Environmental Health and Safety Department San Diego State University (619) 594-6778. Areas of Regulatory Oversight for Laboratory Safety. Radiation Safety Radiation Safety Committee – RUA Mitch Lanahan RSO - (619) 594-6879
Millie Tran and Sheryl Mansour
Environmental Health and Safety Department
San Diego State University
Radiation Safety Committee – RUA
Mitch Lanahan RSO - (619) 594-6879
Institutional Biosafety Committee – BUA
Millie Tran, Sheryl Mansour BSO – (619) 594-2865/6965
Environmental Health & Safety Department
Alvin Shoemaker, Charles Adkins (619) 594-6098/2857 – HazMat/HazWaste
Millie Tran, Sheryl Mansour (619) 594-2865/6965 – Chemical Hygiene
This Laboratory and Field Safety Training is for employees who work in a laboratory or out in the field where hazardous chemicals are being handled or stored.
Cal OSHA Occupational Exposure to Hazardous Chemicals in the Laboratories
The Chemical Hygiene Plan is a chemical safety manual for laboratory workers that contains:
Standard Operating Procedures (SOP's) are written procedures explaining how to safely work with hazardous chemicals.
Lab-specific SOPs are required for any work with hazardous chemical or any application of hazardous operations specific to the protocol or if not already developed in the chemical hygiene plan’s general standard operating procedures.
The Chemical Hygiene Plan (CHP) contains basic SOPs for:
However, labs must create SOPs for procedures/chemicals not in CHP such as :
The Occupational Exposure to Hazardous Chemicals in the Laboratories Regulationis a CalOSHA regulation requiring that lab employees shall be protected from occupational exposure to hazardous chemicals, be informed of the hazardous chemicals present in the lab/field, and be trained before doing any work involving hazardous chemicals in academic and research labs.
Which statement about the Chemical Hygiene Plan is correct?
In order to incorporate safety aspects of handling and storage into your standard operating procedures, you must understand and recognize the hazards associated with the
Chemicals that release energy in a violent fashion either by their natural chemical composition or by the manner they are handled can become a physical hazard. These materials can be safely used if the specific hazard(s) are understood. The main physical hazards at SDSU are:
The National Fire Protection Agency (NFPA) places flammable liquids and combustible liquids in different classes based on their flash points.
Flammable liquid has a flash point below 100° F. Combustible liquid has flashpoints over 100° F.
Examples of common flammable/combustible liquids:
Alcohols- ethanol, methanol, isopropanol
Ketones – acetone
BTX – benzene, toluene, xylene
ethyl ether, ethyl acetate
Most organic chemicals are also flammable or combustible.Flammable & Combustible Liquids
To safely work with flammables observe the following guidelines:
Oxidizers are materials which can react with other substances promoting combustion by giving off electrons and undergoing reduction. These reactions can result in a fire or an explosion.
Examples of common oxidizers are:
To safely work with oxidizers observe the following guidelines:
Peroxidizable chemicals can undergo auto oxidation to form organic peroxides that can become explosive with impact, heat or friction.
These chemicals may become more hazardous as they age; peroxides may form even when the container has not been opened.
Examples of common peroxide formers in SDSU labs include:
Never open a bottle that has solid formation around the lid. (Friction caused by unscrewing the cap can lead to explosion.) Contact the EHS for safe disposal.
Good management of peroxidizable materials starts with:
To safely work with oxidizers observe the following guidelines:
Reactive materials can release heat or a toxic or flammable gas upon contact with water.
Pyrophoric materials can react with air and ignite spontaneously at or below 113°F.
Peroxides and peroxide-forming chemicals:
Compressed gases may pose a physical and/or health hazard depending on the gas being used.
Individually Secured Group Chained
When transporting a cylinder don't forget to:
Poison gases must be stored as follows:
air monitoring and alarm system
A person must be exposed (inhalation, skin absorption, ingestion) to a health hazard for it to cause harm or health effect.
The level and duration of exposure determines the severity of the health effect.
The effects of exposure to hazardous chemicals vary with the amount of exposure or "dose."
We will discuss basic toxicology principles, then specific health effects that a chemical exposure will cause.
The dose-response relationship is important in understanding the cause and effect relationship between chemical exposure and health effects.
All chemicals are toxic at a high enough dose…
Dose- Response Relationship
1- No-effect range (Safe region) 2- Range of increasing effect with increasing dose 3- Maximum effect range
Our goal is to reduce workplace exposures to the level where no adverse effects are observed, into the safe region of the dose-response relationship.
SubstanceLD50 (mg/kg, oral, rat)
Vitamin C 11,900
Ethyl alcohol 7,060
Osmium tetroxide 162 (mouse)
Nicotine & salts 50
How should an LD50 value be used?
Substances associated with the occurrence of cancer in animals or humans are called carcinogens.
Common lab carcinogens and their uses are:
Safe Work Practices
In general, keep exposure as low as possible by:
Sensitizers are a group of chemicals that will cause, through an immune response, the exposed person to become allergic to the chemical. Upon sensitization, small exposures will illicit abnormally severe responses.
Examples of sensitizers:
Mutagens can cause damage to the genes, causing heritable mutations and abnormalities in the offspring.
Teratogens cause harm to the fetus or embryo during pregnancy, but the mother does not show any signs of toxicity.
Corrosives has a low or high pH (<2.0 or >12.5). Therefore, acids and bases are corrosive. If corrosive chemicals come in contact with skin or eyes, they cause irreversible and visible damage at the site of contact. The damage will be acute.
Irritants will cause reversible, but still painful, inflammation when in contact with the skin, eyes, nose or respiratory tract.
The LD50 of a material refers to dose or amount of material that will cause toxic effects in test animals.
The LD50 is the single dose that is lethal to 50% of the animals tested. However, the toxic effects of a chemical are not determined by the LD50.
The risk of exposure to particularly hazardous substances can be reduced by:
Hazard control methods must be implemented by the lab supervisor to reduce employee exposure to hazardous chemicals in the laboratory.
This section covers the three types of hazard control methods to reduce employee exposure to workplace hazards:
One way to control worker exposure to workplace hazards is through policies and procedures. Some examples of the administrative controls used in labs are:
Some points to consider are:
A Material Safety Data Sheet (MSDS) is a valuable reference. It is important to consult an MSDS before introducing a new chemical into a lab protocol or working with hazardous substances.
MSDS shall be received with incoming shipments of hazardous chemicals and shall be readily accessible to lab employees.
Prepared by its manufacturer, an MSDS provides information to help you understand the intrinsic hazards of the chemical including:
Engineering Controls include devices such as fume hoods, glove boxes or other enclosures that reduce exposure or remove contaminants from the work environment.
Fume hoods work by moving air from the lab, into the hood, and exhausting to the outside atmosphere.
Use a chemical fume hood anytime your work involves:
with a PEL <50 mg/kg.
To ensure that airflow is not interrupted, and that the fume hood offers as much protection as possible:
inside the fume hood (behind sash).
(some hoods have an on/off switch).
(between your face and materials in the fume hood).
NOTE:Laminar flow hoods and biosafety cabinetsdo not provide any protection from chemicals.
EHS inspects fume hood performance regularly, and at times may put "Match arrows for proper ventilation" stickers on the hood. Use the hood sash at or lower than the sticker to assure that air speed is adequate.
Personal protective equipment includes any devices or clothing worn by the worker to protect against the hazards in the environment.
Before Entering the Lab
To reduce the risk of latex allergy:
Protective gloves must be worn when there is a potential for a hand injury or skin contact with chemicals, extreme temperatures or abrasives.All protective gloves have limitations. Chemicals will eventually permeate gloves, however they can be safely used for specific time periods when the conditions and use of the chemicals are known.
Protective Glove Recommendations
For prolonged chemical contact or immersion use reusable gloves:
Neoprene - Recommended for corrosives (pH <2.0or >12.5), solvents and alcohols.
Nitrile (Blue or green) - Recommended for non-halogenated solvents
such as hexane, methanol and puncture or abrasion hazards.
Nomex or Zetex - Recommended for temperature extremes
such as handling cryogenic fluids like liquid nitrogen.
Viton - Recommended for chlorinated and aromatic solvents
such as carbon tetrachloride and benzene.
Butyl - Recommended for aldehydes, ketones and esters
such as acetaldehyde, formaldehyde and propanone.
Limitations of reusable gloves: Reusable gloves may limit fine motor skills for specific tasks.
Keep your lab clean!