Chemical Safety

General Safety Guidelines

      Almost everyone works with or around chemicals and chemical products every day. Many
      of these materials have properties that make them hazardous: they can create physical (fire,
      explosion) and/or health hazards (toxicity, chemical burns). However, there are many ways
      to work with chemicals which can both reduce the probability of an accident to a negligible
      level and reduce the consequences to minimum levels should an accident occur. Risk
      minimization depends on safe practices, appropriate engineering controls for chemical
      containment, the proper use of personnel protective equipment, the use of the least quantity of
      material necessary, and substitution of a less hazardous chemical for the more hazardous one.
      Before beginning an operation, ask "What would happen if . . .?" The answer to this question
      requires an understanding of the hazards associated with the chemicals, equipment and
      procedures involved. The hazardous properties of the material and intended use will dictate
      the precautions to be taken.

      Another important distinction is the difference between hazard and risk. The two terms are
      sometimes used as synonyms. In fact, hazard is a much more complex concept because it
      includes conditions of use. The hazard presented by a chemical has two components: (1) its
      inherent capacity to do harm by virtue of its toxicity, flammability, explosiveness,
      corrosiveness, etc.; and (2) the ease with which the chemical can come into contact with a
      person or other object of concern. The two components together determine risk (the
      likelihood or probability that a chemical will cause harm). Thus, an extremely toxic chemical
      such as strychnine cannot cause poisoning if it is in a sealed container and does not contact
      the handler. In contrast, a chemical that is not highly toxic can be lethal if a large amount is
      ingested.

      Chemical safety is inherently linked to other safety issues including laboratory procedures,
      personal protective equipment, electrical safety, fire safety, and hazardous waste disposal.
      Refer to other chapters in this manual for more information on these topics. Knowledge + Common Sense + Caution = Chemical Safety

      Not all chemicals are considered as hazardous. Examples of nonhazardous chemicals
      include buffers, sugars, starches, agar, and naturally occurring amino acids.

      The following sections provide general guidelines for chemical safety.

Chemical Safety Guidelines

      Always follow these guidelines when working with chemicals:

• Assume that any unfamiliar chemical is hazardous.
• Know all the hazards of the chemicals with which you work. For example, perchloric acid is a corrosive, an oxidizer, and a reactive. Benzene is an irritant that is also flammable, toxic, and carcinogenic.
• Consider any mixture to be at least as hazardous as its most hazardous component.
• Never use any substance that is not properly labeled.
• Follow all chemical safety instructions precisely.
• Minimize your exposure to any chemical, regardless of its hazard rating.
• Use personal protective equipment, as appropriate.
• Use common sense at all times.

      The five prudent practices of chemical safety sum up these safety guidelines:

        1. Treat all chemicals as if they were hazardous.

        2. Minimize your exposure to any chemical.

        3. Avoid repeated exposure to any chemical.

        4. Never underestimate the potential hazard of any chemical or combination of chemicals.

        5. Assume that a mixture or reaction product is more hazardous than any component or
            reactant.

Material Safety Data Sheets

      Before using any chemical, read the container label and the appropriate Material Safety Data
      Sheets (MSDSs). Container labels and MSDSs are good sources of information for
      chemical safety. They provide the following information:

• Hazardous ingredients
• Exposure limits
• Physical and chemical characteristics, including the following:

          - Boiling point
          - Vapor pressure

• Physical hazards, including the following:

          - Flammability
          - Explosiveness
          - Reactivity

• Health hazards, including chemicals that are:

- Toxic
- Carcinogens
- Irritants
 

• First-aid procedures
• Proper leak, spill, and disposal techniques
• Proper storage and handling procedures
• Other special provisions 

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Safe Handling Guidelines

      Employees should treat all chemicals and equipment with caution and respect.

      When working with chemicals, remember to do the following:

• Remove and use only the amount of chemicals needed for the immediate job at hand.
• Properly seal, label, and store chemicals in appropriate containers. Keep the containers clearly marked and in a well-ventilated area.
• Check stored chemicals for deterioration and broken containers.
• Learn how to dispose of chemicals safely and legally. Follow TAMU waste disposal requirements.
• Clean up spills and leaks immediately.
• Know what to do in an emergency.

      Likewise, when working with chemicals, remember the following:

• Do not store chemicals near heat or sunlight or near substances which might initiate a dangerous reaction.
• Do not transport unprotected chemicals between the work area and other areas. Use a tray, rack, cart or rubber carrier. Always use a secondary container when transporting hazardous or highly odorous chemicals on an elevator.
• Do not pour hazardous chemicals down the sink.
• Do not put fellow workers or yourself in danger. 

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Hygiene and Chemical Safety

      Good personal hygiene will help minimize exposure to hazardous chemicals.

      When working with chemicals, follow these guidelines:

• Wash hands frequently and before leaving the laboratory. Also, wash hands before eating, drinking, smoking, or applying makeup.
• Remove contaminated clothing immediately. Do not use the clothing again until it has been properly decontaminated.
• Follow any special precautions for the chemicals in use.

      In addition, follow these special precautions:

• Do not eat, drink, smoke, or apply makeup around chemicals.
• Do not wear contact lenses near chemicals, especially corrosives or volatile solvents.
• Do not keep food or food containers anywhere near chemicals.
• Do not use laboratory equipment to serve or store food or drinks.
• Do not sniff or taste chemicals. 

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Hazard Communication Program

      TAMU has a written program (TAMU Hazard Communication Program) that complies with
      OSHA standards and the Texas Hazard Communication Act for hazardous chemicals. This
      program is available from the Environmental Health & Safety Department. It requires the
      following:

• Employee training (including recognition of signs of exposure)
• Labeling procedures
• MSDSs for chemicals at each workplace
• Instructions on how to read and interpret MSDSs
• Chemical inventory reporting procedures
• Recordkeeping requirements
• Emergency response procedures

      Refer to the TAMU Hazard Communication Program and other sections in this manual for
      detailed information on these topics.

      An integral part of hazard communication is hazard identification. Everyone who works with
      hazardous chemicals should know how to read and interpret hazard information. Signs, like
      the NFPA diamond in the illustration below, alert employees to the known hazards in a
      particular location.

      The following is a detailed explanation of the NFPA hazard classification codes:

• Health (Blue):
• 
  4 Can cause death or major injury despite medical treatment
  3 Can cause serious injury despite medical treatment
  2 Can cause injury. Requires prompt medical treatment
  1 Can cause irritation if not treated
  0 No hazard
• Flammability (Red):
• 
  4 Very flammable gases or liquids
  3 Can ignite at normal temperatures
  2 Ignites with moderate heat
  1 Ignites with considerable preheating
  0 Will not burn
• Reactivity (Yellow):
• 
  4 Readily detonates or explodes
  3 May detonate or explode with strong initiating force or heat under confinement
  2 Normally unstable, but will not detonate
  1 Normally stable. Unstable at high temperature and pressure.
  0 Normally stable and not reactive with water.
• Specific Hazard (White):
• Oxidizer - OX
• Acid - ACID
• Alkali - ALK
• Corrosive - COR
• Use No Water - W
• Radioactive - 

Corrosives

      A corrosive chemical destroys or damages living tissue by direct contact. Some acids, bases,
      dehydrating agents, oxidizing agents, and organics are corrosives.

Examples of Corrosives

      Examples of acidic corrosives include the following:

• Hydrochloric acid
• Sulfuric acid

      Examples of alkaline corrosives include the following:

• Sodium hydroxide (lye)
• Potassium hydroxide

      Examples of corrosive dehydrating agents include the following:

• Phosphorous pentoxide
• Calcium oxide

      Examples of corrosive oxidizing agents include the following:

• Halogen gases
• Perchloric acid

      Examples of organic corrosives include the following:

• Phenol
• Acetic acid

      NOTE:
      Concentrated acids can cause painful burns that are often superficial. Inorganic
      hydroxides, however, can cause serious damage to skin tissues because a protective
      protein layer does not form. Even a dilute solution such as sodium or potassium
      hydroxide can saponify fat and attack skin. At first, skin contact with phenol may not
      be painful, but the exposed area may turn white due to the severe burn. Systemic
      poisoning may also result from dermal exposure.

Safe Handling Guidelines for Corrosives

      To ensure safe handling of corrosives, the following special handling procedures should be
      used:

• Always store corrosives properly. Refer to the MSDSs and the Chemical Storage section of this manual for more information.
• Always wear gloves and face and eye protection when working with corrosives. Wear other personal protective equipment, as appropriate.
• To dilute acids, add the acid to the water, not the water to the acid.
• Corrosives, especially inorganic bases (e.g., sodium hydroxide), may be very slippery; handle these chemicals with care and clean any spills, leaks, or dribbles immediately.
• Use a chemical fume hood when handling fuming acids or volatile irritants (e.g., ammonium hydroxide).
• A continuous flow eye wash station should be in every work area where corrosives are present. An emergency shower should also be within 100 feet of the area.

Corrosive Example: Perchloric Acid

      Perchloric acid is a corrosive oxidizer that can be dangerously reactive. At elevated
      temperatures, it is a strong oxidizing agent and a strong dehydrating reagent. Perchloric acid
      reacts violently with organic materials. When combined with combustible material, heated
      perchloric acid may cause a fire or explosion. Cold perchloric acid at less than 70%
      concentration is not a very strong oxidizer, but its oxidizing strength increases significantly at
      concentrations higher than 70%. Anhydrous perchloric acid (>85%) is very unstable and can
      decompose spontaneously and violently.

      If possible, purchase 60% perchloric acid instead of a more concentrated grade. Always
      wear gloves and goggles while using perchloric acid. Be thoroughly familiar with the special
      hazards associated with perchloric acid before using it.

      Heated digestions with perchloric acid require a special fume hood with a wash-down
      system.

Flammables

      A flammable chemical is any solid, liquid, vapor, or gas that ignites easily and burns rapidly in
      air. Consult the appropriate MSDSs before beginning work with flammables.

Flashpoint, Boiling Point, Ignition Temperature, and Class

      Flammable chemicals are classified according to flashpoint, boiling point, ignition
      temperature. Flashpoint (FP) is the lowest temperature at which a flammable liquid gives off
      sufficient vapor to ignite. Boiling point (BP) is the temperature at which the vapor pressure of
      a liquid is equal to the atmospheric pressure under which the liquid vaporizes. Flammable
      liquids with low BPs generally present special fire hazards. The FPs and BPs of certain
      chemicals are closely linked to their ignition temperature — the lowest temperature at which a
      chemical will ignite and burn independently of its heat source.

      The following table illustrates flammable class characteristics:
 

The following table provides examples of common flammables and their flashpoint and class.
 

Conditions for a Fire

      Improper use of flammable liquids can cause a fire. The following conditions must exist for a
      fire to occur:

• Flammable material must be present in sufficient concentration to support a fire (i.e., fuel).
• Oxygen or another oxidizer must be present.
• An ignition source must be present (i.e., heat, spark, etc.).

      The following graphic illustrates the conditions for a fire:

Conditions for a Fire

      When working with flammables, always take care to minimize vapors which act as fuel.

Safe Handling Guidelines for Flammables

      Follow these guidelines when working with flammable chemicals:

• Handle flammable chemicals in areas free from ignition sources.
• Never heat flammable chemicals with an open flame. Use a water bath, oil bath, heating mantle, hot air bath, etc.
• Use ground straps when transferring flammable chemicals between metal containers to avoid generating static sparks.
• Use a fume hood when there is a possibility of dangerous vapors. (Ventilation will help reduce dangerous vapor concentrations.)
• Restrict the amount of stored flammables, and minimize the amount of flammables present in a work area.
• Remove from storage only the amount of chemical needed for a particular experiment or task.

Solvents

      Organic solvents are often the most hazardous chemicals in the work place. Solvents such as
      ether, alcohols, and toluene, for example, are highly volatile or flammable. Chlorinated
      solvents such as chloroform are nonflammable, but when exposed to heat or flame, may
      produce carbon monoxide, chlorine, phosgene, or other highly toxic gases.

      Always use volatile and flammable solvents in an area with good ventilation or in a fumehood.
      Never use ether or other highly flammable solvents in a room with open flames or other
      ignition sources present.

Solvent Exposure Hazards

      Health hazards associated with solvents include exposure by the following routes:

• Inhalation:

          Inhalation of a solvent may cause bronchial irritation, dizziness, central nervous system
         depression, nausea, headache, coma, or death. Prolonged exposure to excessive
         concentrations of solvent vapors may cause liver or kidney damage. The consumption of
         alcoholic beverages can enhance these effects.

• Skin contact:

         Skin contact with solvents may lead to defatting, drying, and skin irritation.

• Ingestion:

          Ingestion of a solvent may cause severe toxicological effects. Seek medical attention
          immediately.

      The odor threshold for the following chemicals exceeds acceptable exposure limits.
      Therefore, if you can smell it, you may be overexposed — increase ventilation immediately.

• Chloroform
• Benzene
• Carbon tetrachloride
• Methylene chloride

      NOTE:
      Do not depend on your sense of smell alone to know when hazardous vapors are
      present. The odor of some chemicals is so strong that they can be detected at levels far
      below hazardous concentrations (e.g., xylene).

      In addition, some solvents (e.g., benzene) are known or suspected carcinogens.

Reducing Solvent Exposure

      To decrease the effects of solvent exposure, substitute hazardous solvents with less toxic or
      hazardous solvents whenever possible. For example, use hexane instead of diethyl ether,
      benzene or a chlorinated solvent.

           NOTE:
           The best all-around solvent is water; use it whenever possible.

      The following table outlines possible solvent substitutions:
 

Solvent Example:

DMSO

      Dimethyl sulfoxide is unique because it is a good solvent with many water-soluble as well as
      lipid-soluble solutes. Due to these properties, dimethyl sulfoxide is rapidly absorbed and
      distributed throughout the body. It can also facilitate absorption of other chemicals such as
      grease, oils, cosmetics, and other chemicals that may contact the skin.

Toxic Chemicals

 
       The toxicity of a chemical refers to its ability to damage an organ system (kidneys, liver),
      disrupt a biochemical process (e.g., the blood-forming process) or disturb an enzyme system
      at some site remote from the site of contact. Toxicity is a property of each chemical that is
      determined by molecular structure. Any substance can be harmful to living things. But, just as
      there are degrees of being harmful, there are also degrees of being safe. The biological
      effects (beneficial, indifferent or toxic) of all chemicals are dependent on a number of factors.

      For every chemical, there are conditions in which it can cause harm and, conversely, for
      every chemical, there are conditions in which it does not. A complex relationship exists
      between a biologically active chemical and the effect it produces that involves consideration
      of dose (the amount of a substance to which one is exposed), time (how often, and for how
      long during a specific time, the exposure occurs), the route of exposure (inhalation, ingestion,
      absorption through skin or eyes), and many other factors such as gender, reproductive
      status, age, general health and nutrition, lifestyle factors, previous sensitization, genetic
      disposition, and exposure to other chemicals.

      The most important factor is the dose-time relationship. The dose-time relationship forms the
      basis for distinguishing between two types of toxicity: acute toxicity and chronic toxicity. The
      acute toxicity of a chemical refers to its ability to inflict systemic damage as a result (in most
      cases) of a one-time exposure to relative large amounts of the chemical. In most cases, the
      exposure is sudden and results in an emergency situation.

      Chronic toxicity refers to a chemical's ability to inflict systemic damage as a result of repeated
      exposures, over a prolonged time period, to relatively low levels of the chemical. Some
      chemicals are extremely toxic and are known primarily as acute toxins (hydrogen cyanide);
      some are known primarily as chronic toxins (lead). Other chemicals, such as some of the
      chlorinated solvents, can cause either acute or chronic effects.

      The toxic effects of chemicals can range from mild and reversible (e.g. a headache from a
      single episode of inhaling the vapors of petroleum naphtha that disappears when the victim
      gets fresh air) to serious and irreversible (liver or kidney damage from excessive exposures
      to chlorinated solvents). The toxic effects from chemical exposure depend on the severity of
      the exposures. Greater exposure and repeated exposure generally lead to more severe
      effects.

      Exposure to toxic chemicals can occur by:

• Inhalation
• Dermal absorption
• Ingestion
• Injection

          NOTE:
          Inhalation and dermal absorption are the most common methods of chemical
          exposure in the workplace.

      The following sections provide examples and safe handling guidelines for the following types
      of toxic chemicals:

• Toxicants
• Carcinogens
• Reproductive Toxins
• Sensitizers
• Irritants

          IMPORTANT:
          Minimize your exposure to any toxic chemical.

Acute Toxins

      Acute toxins can cause severe injury or death as a result of short-term, high-level exposure.

      Examples of acute toxins include the following:

• Hydrogen cyanide
• Hydrogen sulfide
• Nitrogen dioxide
• Ricin
• Organophosphate pesticides
• Arsenic

      Do not work alone when handling acute toxins. Use a fume hood to ensure proper
      ventilation.

Chronic Toxins

      Chronic toxins cause severe injury after repeated exposure.

      Examples of chronic toxins include the following:

• Mercury
• Lead
• Formaldehyde

Carcinogens

      Carcinogens are materials that can cause cancer in humans or animals. Several agencies
      including OSHA, NIOSH, and IARC are responsible for identifying carcinogens. There are
      very few chemicals known to cause cancer in humans, but there are many suspected
      carcinogens and many substances with properties similar to known carcinogens.

      Examples of known carcinogens include the following:

• Asbestos
• Benzene
• Tobacco smoke
• Chromium, hexavalent
• Aflatoxins

      Zero exposure should be the goal when working with known or suspected carcinogens.
      Workers who are routinely exposed to carcinogens should undergo periodic medical
      examinations.

Reproductive Toxins

      Reproductive toxins are chemicals that can produce adverse effects in parents and
      developing embryos. Chemicals including heavy metals, some aromatic solvents (benzene,
      toluene, xylenes, etc.), and some therapeutic drugs are capable of causing these effects. In
      addition, the adverse reproductive potential of ionizing radiation and certain lifestyle factors,
      including excessive alcohol consumption, cigarette smoking, and the use of illicit drugs, are
      recognized.

      While some factors are known to affect human reproduction, knowledge in this field
      (especially related to the male) is not as broadly developed as other areas of toxicology. In
      addition, the developing embryo is most vulnerable during the time before the mother knows
      she is pregnant. Therefore, it is prudent for all persons with reproductive potential to minimize
      chemical exposure.

Sensitizers

      Sensitizers may cause little or no reaction upon first exposure. Repeated exposures may
      result in severe allergic reactions.

      Examples of sensitizers include the following:

• Isocyanates
• Nickel salts
• Beryllium compounds
• Formaldehyde
• Diazomethane

Irritants

      Irritants cause reversible inflammation or irritation to the eyes, respiratory tract, skin, and
      mucous membranes. Irritants cause inflammation through long-term exposure or high
      concentration exposure. For the purpose of this section, irritants do not include corrosives.

      Examples of irritants include the following:

• Ammonia
• Formaldehyde
• Halogens
• Sulfur dioxide
• Poison ivy
• Phosgene

Reactives and Explosives

Reactive chemicals are sensitive to either friction or shock or they react in the presence of air, water, light, or heat. Explosive chemicals decompose or burn very rapidly when subjected to shock or ignition. Reactive and explosive chemicals produce large amounts of heat and gas; they are extremely dangerous.

Examples of reactive compounds include the following:
 

Cleaning Agents

      Many of the chemicals contained in cleaning agents are corrosive. Follow these guidelines
      when working with any cleaning agent:

• Always read and understand the label instructions or the MSDS before using any cleaning agent.
• Mix solutions to the recommended strength.
• When diluting acid with water, always add the acid to the water, not the water to the acid. (Concentrated acids may splatter when mixed improperly.)
• Wear appropriate eye protection and gloves for the job (e.g., neoprene, nitrile, or rubber).
• Do not leave aerosol cans in direct sunlight or areas where the temperature may exceed 120^øF. Heated aerosol cans may explode.

The following table outlines common cleaning agents, their hazards, and safety precautions:
 

Fume Hoods

      Fume hoods provide primary confinement in a chemical laboratory. They exhaust toxic,
      flammable, noxious, or hazardous fumes and vapors by capturing, diluting, and removing
      these materials. Fume hoods also provide physical protection against fire, spills, and
      explosion. Fume hoods provide the best protection when the fume hood sash is in the closed
      position. All chemical fume hoods must be ducted to the outside of the building.

Types of Fume Hoods

      There are three basic types of fume hoods: (1) standard, (2) bypass, and (3) auxiliary air. In
      addition, at TAMU, there are three classes of fume hoods: A, B, and C.

      STANDARD FUME HOODS
      The face velocity of a standard fume hood is inversely related to the open face area, allowing
      a constant volume of air to be exhausted. If the sash is lowered, the inflow air velocity
      increases.

          IMPORTANT:
          Face velocity that is too high may disturb sensitive apparatus, extinguish Bunsen
          burners, or create excessive turbulence.

Standard Fume Hood

      BYPASS FUME HOODS
      Bypass fume hoods are also called "balanced air" or "constant volume" fume hoods. As the
      sash is lowered, bypass fume hoods allow constant exhaust volumes that help keep the room
      ventilation system balanced. Constant exhaust volumes also eliminate the problem of high
      face velocity as the sash is lowered.

Bypass Fume Hood: Sash Open and Closed

      AUXILIARY AIR FUME HOODS
      Auxiliary air fume hoods are also known as "supplied air" hoods. They use an outside air
      supply for 50% to 70% of the hood's exhaust requirements. This type of hood is designed to
      reduce utility costs and conserve energy. The face velocity of an auxiliary air fume hood may
      vary.

Auxiliary Air Fume Hood: Sash Open and Closed

Classifications

      CLASSIFICATION TYPES
      The following guidelines are recommendations for face velocities of three classes of chemical
      fume hoods.

• Class A Fume Hood:

          Recommended average face velocity is 115 to 125 fpm with a minimum of 100 fpm at any
          point. This class of hood is suitable for use with highly toxic or volatile materials having a
          TLV of less than 1 ppm (e.g., tetraethyl lead, beryllium compounds, metal carbonyls, and
          carcinogens).

• Class B Fume Hood:

          Recommended average face velocity is 95 to 110 fpm with a minimum of 80 fpm at any
          point. This class of hood is suitable for use with materials having a TLV of 1-100 ppm
          (e.g., acids, formaldehyde, chloroform, and phenol).

• Class C Fume Hood:

          Recommended average face velocity is 75 to 95 fpm with a minimum of 60 fpm at any
          point. This class of fume hood is suitable for use with materials having a TLV greater than
          100 ppm (e.g., ethanol, butanol, and acetone). It is also suitable for operations that create
          nuisance dust and fumes.

Special Fume Hoods

      Special fume hoods are necessary when working with certain chemicals and operations.
      Examples of special fume hoods include the following:

• Perchloric acid fume hoods:

          These fume hoods have a water spray system to wash down the entire length of the
          exhaust duct, the baffle, and the wall. The water spray is used periodically or after each use
          to remove any perchloric acid or organic material that may have accumulated.

• Walk-in hoods:

          These fume hoods have single vertical sashes or double vertical sashes and an opening that
          extends to the floor. These hoods are typically used to accommodate large pieces of
          equipment.

• Radioisotope hoods:

          These hoods are labeled for use with radioactive materials. The interior of these hoods is
          resistant to decontamination chemicals. If special filtration is necessary with these fume
          hoods, contact the Environmental Health & Safety Department.

• Canopy hoods:

          These hoods capture upward moving contaminants and are good for heat-producing
          operations. Workers may be exposed to contaminants if they work under the hood,
          however.

Perchloric Acid Fume Hood

Canopy Fume Hood

Fume Hood Safety Considerations

      The potential for glass breakage, spills, fires, and explosions is great within a fume hood. Due
      to the chance for fires or explosions, fume hoods should be located towards the back of a
      laboratory, away from primary and secondary exits. Practice safe work habits when working
      with fume hoods, including the following:

• Air Flow and Ventilation:

      Employee traffic in front of a fume hoods or opening/closing laboratory doors can interfere
      with hood performance. Ensure that there is sufficient aisle space in front of fume hoods.

• Fume Hood Type:

      All fume hoods are not appropriate for all types of work. Ensure that hazardous chemicals
      are used in the proper type or class of hood. For example, use perchloric acid only in fume
      hoods specifically designed for perchloric acid.

Fume Hood Use and Care

      To ensure safety and proper fume hood performance, follow these guidelines:

• Use a fume hood when working with chemicals or procedures that may produce hazardous fumes or vapors.
• Know how to properly operate a fume hood before beginning work. Inspect the fume hood before starting each operation.
• Place equipment and chemicals at least six inches behind the fume hood sash. This practice reduces the chance of exposure to hazardous vapors.
• Do not allow paper or other debris to enter the exhaust duct of the hood.
• Do not store excess chemicals or equipment in fume hoods.
• Do not block the baffle area of the fume hood.
• Elevate any large equipment within the hood at least three inches to allow proper ventilation around the equipment.
• When working in a fume hood, set the sash at the height indicated by the arrow on the inspection sticker. The only time the sash should be completely open is while setting up equipment.
• Wear personal protective equipment, as appropriate.
• Do not alter/modify the fume hood or associated duct work.
• Clean up spills in the hood immediately.

          IMPORTANT:
          If a power failure or other emergency occurs (e.g., building fire or fire within the
          fume hood), close the fume hood sash and call for emergency assistance.

Fume Hood Inspections

      Fume hoods should be tested at least annually. Fume hoods should also be tested in the
      following circumstances:

• When an employee requests an inspection
• When a procedural change requires a hood classification upgrade
• After major repair work
• After a fume hood is moved

      The Environmental Health & Safety Department performs fume hood inspections and testing.
      The test includes an inspection of the hood system, airflow measurements, and an assessment
      of the use of the fume hood. If you suspect a problem with your fume hood, please contact
      the Environmental Health & Safety Department.

Spill Response

      Spills are likely whenever chemicals are used. Personnel should be trained and equipped to
      handle most of the spills in their work area. The Environmental Health & Safety
      Department has a trained and equipped Chemical Spill Response Team (CSRT). Contact
      the Environmental Health & Safety Department for assistance or advice about a chemical
      spill.

Spill Prevention and Planning

      Prevention is the best safety strategy for any environment. Use safe handling procedures and
      be aware of the potential hazards associated with chemicals. For example, before working
      with any chemicals, review the appropriate MSDSs.

      Be prepared to respond to a chemical spill. To prepare for a potential spill, follow these
      guidelines:

• Develop and periodically review written procedures for an emergency response plan.
• Keep a fully stocked chemical spill response kit available.
• Know the location and proper use of cleanup materials.
• Know how to turn off equipment, heat sources, electrical panels, etc.
• Review appropriate MSDSs.

Spill

Response Kit

      Work areas that contain potentially hazardous chemicals should have a chemical spill
      response kit. This kit should include the following:

• Disposable laboratory/surgical gloves
• Disposable vinyl gloves
• Safety goggles
• Absorbent (e.g., spill pillows, vermiculite, litter box filler, etc.)
• Plastic scoop
• Plastic trash bags

Responding to Chemical Spills

      The following sequence provides a brief overview of proper chemical response procedures:

      1. Notify others in the immediate area that a spill has occurred. Evacuate the area if
           necessary.

      2. Attend to injured and exposed people.

      3. Identify the spilled chemical(s).

      4. Based on the hazards and the personal protective equipment needed (e.g., respiratory
          protection), determine if you can safely clean the spill or if assistance is necessary. (Most
          spills can be cleaned safely by the people who were using the chemical.)

      If you determine that you can safely clean the spill without emergency assistance, follow these
      guidelines:

• Wear appropriate protective clothing and equipment.
• Have another person stand by during the cleanup.
• Clean up the spill and collect all wastes for proper disposal.
• Ventilate the area, as necessary, before it is reoccupied.
• Decontaminate reusable cleanup supplies such as scoops, rubber boots, etc.
• Restock the chemical spill kit and return it to the normal storage location.

      Do not take unnecessary risks with chemical spills. Call the Environmental Health & Safety
      Department whenever a spill involves the following:

• Large volume of spilled material
• Very hazardous material
• Very hazardous conditions (e.g., fire, explosion, toxicity, etc.)
• Strong odor
• Personnel injury or exposure

Chemical Storage

      Proper chemical storage is as important to safety as proper chemical handling. Often,
      seemingly logical storage ideas, such as placing chemicals in alphabetical order, may cause
      incompatible chemicals to be stored together.

General Guidelines

      Follow these guidelines for safe chemical storage:

• Read chemical labels and MSDSs for specific storage instructions.
• Store chemicals in a well-ventilated area; however, do not store chemicals in a fume hood.
• Maintain an inventory of all chemicals in storage.
• Return chemical containers to their proper storage location after use.
• Store glass chemical containers so that they are unlikely to be broken.
• Store all hazardous chemicals below eye level.
• Never store hazardous chemicals in a public area or corridor.

Separating Hazardous Chemicals

      In addition to the guidelines above, there are storage requirements for separating hazardous
      chemicals. Because an alphabetical storage system may place incompatible chemicals next to
      each other, group chemicals according to their hazard category (i.e., acids, bases,
      flammables, etc.).

      Follow these guidelines to ensure that hazardous chemicals are stored safely:

• Separate acids from bases. Store these chemicals near floor level.
• Isolate perchloric acid from organic materials. Do not store perchloric acid on a wooden shelf.
• Separate highly toxic chemicals and carcinogens from all other chemicals. This storage location should have a warning label and should be locked.
• Separate acids from flammables.
• Do not keep peroxide-forming chemicals longer than twelve months.
• Do not allow picric acid to dry out.
• If flammables need to be chilled, store them in a laboratory-safe refrigerator, not in a standard refrigerator.
• Flammables should be stored in a flammable storage cabinet.

      The following table provides examples of incompatible chemicals:
 

Shipping/Receiving Chemicals

      The U.S. Department of Transportation regulates the shipment of hazardous materials.
      Anyone who packages, receives, unpacks, signs for, or transports hazardous chemicals must
      be trained and certified in Hazardous Materials Transportation. Warehouse personnel,
      shipping and receiving clerks, truck drivers, and other employees who pack or unpack
      hazardous materials must receive this training. Contact the Environmental Health & Safety
      Department for more information on shipping or receiving hazardous chemicals.