Laboratory and Field Safety by liuqingyan



           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

   Biological Safety
      Institutional Biosafety Committee – BUA
      Millie Tran, Sheryl Mansour BSO – (619) 594-2865/6965

   Chemical Safety
      Environmental Health & Safety Department
      Alvin Shoemaker, Charles Adkins (619) 594-6098/2857 – HazMat/HazWaste
      Millie Tran, Sheryl Mansour (619) 594-2865/6965 – Chemical Hygiene
    Work with Hazardous

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 Regulation

Cal OSHA Occupational Exposure to Hazardous Chemicals in the Laboratories

   The California Occupational Safety Health Administration (Cal OSHA) has determined that lab
    or field work typically differ from industrial operations in the handling and use of hazardous
    chemicals; thus, establishing the Occupational Exposure to Hazardous Chemicals in the
    Laboratories Regulation to protect lab or field workers.

   The key elements of this regulation are as follow:

        A written Chemical Hygiene Plan must be created and accessible to employees when
         hazardous chemicals or hazardous operations are involved.
        Employees shall be protected from occupational exposure to hazardous chemicals.
        Employees shall be provided and informed of the Material Safety Data Sheets (MSDSs)
         and other reference material.
        Employees shall be informed of the hazardous chemicals present in the lab/field or of the
         hazardous operations in which they are involved.
        Employees handling hazardous chemicals must be appropriately trained before doing any
         work involving hazardous chemicals or hazardous operations.
        Engineering controls and personal protective equipment must be provided, maintained, and
         replaced when necessary.
        Employees must be informed of the procedures to follow to respond to emergencies.
Basically, this CalOSHA regulation requires
the following provisions to ensure health and
safety of lab/field employees handling
hazardous chemicals:

 Avoid underestimation of risk
 Minimize all chemical exposures
 Observe exposure limits
 Institute chemical hygiene plan
         Chemical Hygiene Plan

The Chemical Hygiene Plan is a chemical safety manual for
  laboratory workers that contains:

   Basic standard operating procedures (SOPs).
    (Lab-specific SOPs must be created.)
   Criteria used to determine and implement control measures
    from exposure to hazardous chemicals.
   Circumstances requiring prior approval before application of
    hazardous lab operation, procedure or activity.
   Provision for additional employee protection for work with
    particularly hazardous substances such as “select
    carcinogens”, reproductive toxins, and highly acute toxins.
           Standard Operating Procedures
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

The Chemical Hygiene Plan (CHP) contains basic SOPs for:
 Handling Common Hazardous Chemicals
 Labeling of Chemicals
 Storing of Chemicals
 Responding to Small Lab Spills

However, labs must create SOPs for procedures/chemicals not in CHP such as :
 Select Carcinogens
 Highly Toxic Chemicals
 The Occupational Exposure to Hazardous
 Chemicals in the Laboratories Regulation is 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

   True
   False
  Which statement about the Chemical Hygiene
  Plan is correct?

A.   It is a campus policy.
B.   It contains general Standard Operating
     Procedures (SOP) that must be supplemented
     with lab-specific SOPs.
C.   All lab staff must be familiar with it.
D.   All of the above.

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
   materials,
   equipment used, and
   procedures performed.
          Physical Hazards

    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:

   Flammable and Combustible Liquids
   Oxidizers
   Peroxidizable chemicals
   Explosives
   Reactive materials
   Pyrophoric
   Compressed gases
            Flammable & Combustible
    Flammable & combustible liquids are some of the most
    commonly used hazardous chemicals at SDSU.
   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
            Flammable & Combustible
    To safely work with flammables
    observe the following guidelines:
   Keep flammables/combustible materials away
    from sources of ignition, open flames, hot
    surfaces, electrical equipment and static
    electricity. Do not store with acids or bases.

   Store flammable liquids in NFPA approved
    containers or inside cabinets or storage rooms
    designed for flammable materials.

   Small squirt bottles containing a volume of less
    that one-liter can be stored on the bench top.
    Larger volumes (>1 liter) need to be stored

   Assure fire extinguishers are in the area.
      Oxidizing Chemicals

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:
  Nitrous oxide
  Hydrogen peroxide
  Nitric acid
  Perchloric acid
  Nitrates
  Oxygen
  Sulfuric acid
         Oxidizing Chemicals

To safely work with oxidizers observe
 the following guidelines:

   Oxidizers are incompatible with organics. Store oxidizers
    separate from organics.

   Use oxidizers with extreme care and consult the MSDS
    for specific guidelines.
        Peroxidizable Chemicals

Peroxidizable chemicals can undergo auto
oxidation to form organic peroxides that can
become explosive with impact, heat or

These chemicals may become more
hazardous as they age; peroxides may form
even when the container has not been

Examples of common peroxide formers in
SDSU labs include:
    Ether
    Dioxanes
    Isopropyl ether             Never open a bottle that has solid formation around the
    Tetrahydrofuran             lid. (Friction caused by unscrewing the cap can lead to
                                       explosion.) Contact the EHS for safe disposal.
         Peroxidizable Chemicals
Good management of peroxidizable materials starts

   Dating all peroxide formers upon receipt and again after opening

   Dispose of, or test for peroxide formation at the expiration date or 18
    months if the container has not been opened.

To safely work with oxidizers observe the following

   Never open a bottle that has solid formation around the lid. (Friction
    caused by unscrewing the cap can lead to explosion.) Contact EHS
    for safe disposal.
           Reactive and Pyrophoric

Reactive materials can release heat or a toxic or flammable gas upon contact with

    Safe handling of these materials will depend on the specific materials and the conditions in which
     this material is handled.

    Consult the MSDS for the specific chemical for safe handling instructions and to develop an SOP
     for the operation.

        Sodium metal
        Lithium aluminum hydride

Pyrophoric materials can react with air and ignite spontaneously at or below 113°F.

    Pyrophoric materials should be handled and stored in inert environments.

        silane
        white or yellow phosphorous
  Peroxides and peroxide-forming chemicals:

A.   Must be dated when received and when opened.
B.   Can explode if subject to heat, shock or friction.
C.   Should be tested for peroxide formation at the
     expiration date because they become more
     hazardous as they age.
D.   All of the above.
        Compressed Gases
Compressed gases may pose a physical and/or health hazard
depending on the gas being used.

   Gas cylinders with regulators must be individually secured.
   Only cylinders with safety caps can be group chained.

Individually Secured                         Group Chained

When transporting a cylinder don't forget to:
   Use appropriate cart
   Secure cylinder in an upright position
   Make sure safety cap is in place
    Compressed gas containers must be handled with care and should be stored
    taking into account the property and hazard of the gases contained. This
    information can be found in the MSDS of the material.

   Store in areas separate from external heat sources such as flame impingement,
    intense radiant heat, electric arc, or high temperature steam lines.

   Store at least 20 feet from highly combustible materials such as oil or grease.

   Store or transport in a manner to prevent them from tipping, falling or rolling.
   Flammable gases (i.e. propane, hydrogen) must be stored in areas
    away from sources of ignition and kept separate from oxidizing gases
    (i.e. oxygen).

   Poison/toxic gases (NFPA H=3 or 4) i.e. chlorine, carbon monoxide,
    phosgene or ammonia can pose serious potential hazards to personnel
    and therefore special storage and handling measures are required.

    Poison gases must be stored as follows:
        Small size cylinders (fit inside hood)
             Use and storage in hood

        Large size cylinders (regular use) –
             Use and store in ventilated cabinets with
              air monitoring and alarm system
Health Hazards

 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."
            Health Hazard
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.
            Lethal Dose 50
   One of the most commonly used measures of toxicity is the LD50. The LD50 is
    one way to measure the short-term poisoning potential (acute toxicity) of a

   The LD50 is the single dose that is lethal to 50% of the animals tested. A
    chemical with a low LD50, like osmium tetroxide is highly toxic.
   The LD50 however, says nothing about the non-lethal toxic effects of
    chemicals. Some chemicals may have a high LD50, but may produce toxic
    effects at very small exposure levels, Sulfuric acid has an oral (rat) LD50 of
    2,140 mg/kg, but may be corrosive at concentrations as low as 15%, causing
    severe burns at very low quantities.
LD50 values for substances tested in the rat

   Substance                             LD50 (mg/kg, oral, rat)
   Vitamin C                             11,900
   Ethyl alcohol                         7,060
   Bromine                               2,600
   Osmium tetroxide                      162 (mouse)
   DDT                                   100
   Nicotine & salts                      50

How should an LD50 value be used?
 As an aid in developing emergency procedures in case of a major spill or accident.
 As an aid in developing guidelines for the use of appropriate safety clothing and
  equipment. For example, if the dermal LD50 value for a chemical is rated as extremely
  toxic, it is important to protect the skin with clothing and gloves made of the right chemical-
  resistant material.
 As part of the Material Safety Data Sheets. Remember, the LD50 is only an approximate
  figure so that lethal toxicity can be compared. It says nothing about levels at which other
  acute toxic, but non-lethal effects might occur.
           Permissible Exposure Limit
   PELs are regulatory limits on the amount or concentration of a
    substance in the air. PEL's are based on an 8-hour adult time weighted
    average (TWA) exposure.
   PEL's refer to airborne concentrations of substances that may be
   When working with materials that have a low PEL (< 50ppm), use
    administrative and engineering controls to minimize the generation of a
    vapors or dust in the first place. If these controls are not sufficient, use
    appropriate personal protective equipment.
Substances associated with the occurrence of cancer in animals or
  humans are called carcinogens.

   In the research laboratory, chemicals that have been deemed to be
    carcinogens will be labeled as such on the manufacturer's bottle. As
    with other chemicals, MSDS will provide further detail about the
    chemical hazards, means of exposure and necessary precautions.
    Further, a list of carcinogens can be found in the CHP.
   Carcinogens are a chronic hazard. That is, they do not cause harm
    upon initial exposure, but rather take repeated exposures over many

Common lab carcinogens and their uses are:
        Chloroform - laboratory solvent
        Formaldehyde - tissue preservation
        Carbon tetrachloride - laboratory solvent
Safe Work Practices

In general, keep exposure as low as possible by:
 Using engineering controls, such as fume hoods or glove
 Using PPE such as eye protection, lab coat and gloves.
 Keeping quantities to a minimum.
 Labeling bottle and storage area with the words carcinogen
   or cancer hazard.
 Developing an SOP.

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.

   A common lab example is formaldehyde. Exposure to
    formaldehyde/formalin can cause a sore throat and other respiratory
    problems if inhaled, and eczema-like symptoms upon repeated skin
   Sensitization can occur either from skin contact, or from inhalation.
   Note that a person who has allergic reactions to a chemical upon the
    first exposure is considered a sensitive individual.
   Sensitizers are also chronic health hazard.

Examples of sensitizers:
        Formaldehyde/Formalin
        Latex
             Reproductive Hazards

   Reproductive toxicity is a sub-chronic hazard that some research chemicals
    have. These can be either mutagens or teratogens.

Mutagens can cause damage to the genes, causing heritable mutations and
  abnormalities in the offspring.

        Ethidium bromide
        Formaldehyde, nicotine

Teratogens cause harm to the fetus or embryo during pregnancy, but the mother
   does not show any signs of toxicity.

        Ethyl alcohol
        Mercury compounds
               Corrosives and Irritants
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.
      Hydrochloric acid
      Ammonium hydroxide
      Acetic acid

Irritants will cause reversible, but still painful, inflammation when in contact with the skin, eyes, nose or
     respiratory tract.
        Chlorine and ammonia containing products
        Diluted acids
        Halogens
        Nitrogen dioxide
        Alkaline dusts and mists
        Ozone
        Phosphorus chlorides
        Hydrogen chloride
        Phosgene
        Arsenic trichloride
        Hydrogen fluoride
        Diethyl/dimethyl sulfate
 The LD50 of a material refers to dose or
 amount of material that will cause toxic
 effects in test animals.

 True
 False

 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.
         Minimizing Contact with
The risk of exposure to particularly hazardous
  substances can be reduced by:

   Substituting whenever possible for less toxic
    /hazardous materials
   Using as little material as possible
   Handling inside a fume hood
   Minimizing contact by the use of Personal
    Protective Equipment
   Developing a written SOP for operations involving
    highly toxic materials
           Chemical Storage Guidelines

   The storage area and cabinets should be labeled to identify the hazardous
    nature of the products stored within.

 Ensure that all chemicals are stored according to compatibility. (e.g.,
oxidizers such as sulfuric and nitric acid away from organics such as acetic
acid and acetone).
Flammables storage

   Flammable materials kept outside a cabinet should
    be in safety cans.
   Flammable liquids (>1L) must be stored inside
    flammable cabinets. Never store flammable liquids
    in a standard (non-explosion/fire proof) cabinet.
    Example: i.e. acetone, hexane, acetic acid, phenol,
    and chloroform
   Flammables include organic liquids, combustibles,
    organic acids and halogenated solvents.
    Halogenated solvents are not flammable, but this is
    the appropriate place to store them.
Acids Storage
 Store by acid class in separate secondary containment
    Organic
           Acetic Acid
           Formic Acid
           Citric Acid
           Benzoic Acid
           Butyric Acid
           Propionic Acid

      Inorganic
           Hydrochloric Acid
           Hydrofluoric Acid
           Hydrobromic Acid
           Phosphoric Acid
           Chromic Acid

      Oxidizing
           Nitric Acid
           Perchloric Acid
           Sulfuric Acid
Bases Storage
   Store in secondary containment
   Store away from acids and solvents
   Cannot be stored at or above eye level.
   Examples:
       Hydroxides
       Amines
       Ammonia
       Bleach
   Corrosive and flammable materials should be stored below
    eye level.
   Dry chemicals can be stored on shelves.

   Chemicals should not be stored on the floor except in
    approved shipping containers.
   Concentrated perchloric acid should be stored alone in a
    cabinet by itself.
      Hazard Control Methods

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:
   Administrative controls
   Engineering controls
   Personal protective equipment
       Administrative Controls

One way to control worker exposure to workplace hazards
is through policies and procedures. Some examples of the
administrative controls used in labs are:

   The SDSU CHP.
   Standard Operating Procedures.
   Lab-Specific SOP Training.
   Chemical Labeling.
   Material Safety Data Sheets.
   Security Training.
Lab Security
Some points to consider are:
   Recognize that laboratory security is related to but
    different from laboratory safety and develop a site-
    specific security policy.
   Control access to areas where hazardous materials are
    used and stored.
   Know who is in your laboratory area.
   Know what materials are being brought into your lab.
   Know what materials are being removed from your lab.
   Have a protocol for reporting security incidents.
Material Safety Data Sheets
  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:
      Physical and chemical properties
      Reactivity and stability information
      Physical and Health Hazards
      Acute and chronic toxicity information
      Permissible exposure limits
      Exposure control measures
      Handling and storage information
      Waste disposal
        Engineering Controls
Engineering Controls include devices such as fume
hoods, glove boxes or other enclosures that reduce
exposure or remove contaminants from the work

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:
       Toxic volatile materials (chloroform, formaldehyde)
        with a PEL <50 mg/kg.
       Carcinogens or particularly hazardous substances.
       A procedure that may create an aerosol of a toxic substance.
       Reactive or explosive materials or chemicals that may spatter.
       Toxic gases (NH3, CO, F).
Safe Operation of Chemical Fume Hoods
   To ensure that airflow is not interrupted, and that the fume hood offers as much
   protection as possible:

    Keep sources of emission at least 6 inches
     inside the fume hood (behind sash).
    Minimize storage of chemicals in the hood.
    Avoid blocking off baffle exhausts.
    Ensure that blower is working
     (some hoods have an on/off switch).
    Work with sash at proper operating level
     (between your face and materials in the fume hood).
    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.

NOTE: Laminar flow hoods and biosafety cabinets do not provide any protection
  from chemicals.
              Personal Protective Equipment
    Personal protective equipment includes any devices or clothing worn by the
    worker to protect against the hazards in the environment.

    Examples are:
        Lab coats,
        protective gloves,
        safety glasses,
        goggles,
        and face shields.

    Before Entering the Lab
   Make sure that you minimize exposed skin at all times by wearing the
    appropriate clothing (long sleeves/pants, close toed shoes). The appropriate
    personal protective equipment must be used at all times in the lab when
    chemical, radioactive, or biohazardous materials are being handled.
   It is advised to wear PPE even if not working with hazardous material, because
    you can be injured by someone else's accident!
Glove Selection and Use
   Protective gloves are an important aspect of protection against hazardous
    materials. The use of protective gloves can reduce the risk of a hand injury
    by 40%.
   It is critical that users select the correct glove material based on the
    chemicals used and the permeation data.
   The natural rubber proteins found in latex gloves may produce an allergic
    reaction with sensitive individuals. Some people may develop an allergy
    from latex after repeated use of latex products. The use of powdered gloves
    may take the allergic reaction much worse because the powder becomes
    airborne, carrying latex proteins, which are then inhaled.
  To reduce the risk of latex allergy:
   Substitute non-latex gloves when ever possible or use powder free, reduced
    protein content.
Glove Use
    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.
     Chemical Storage
General Rule
 Food containers MUST NEVER BE USED
  for chemical storage.
      Chemical Storage

 Provide earthquake restraints for all shelving
  where chemicals or glassware are stored.
 Provide secondary containment if there is a
  risk or spill or release.
A Cluttered Lab is a
Dangerous Lab!

       Keep your lab clean!

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