Lab Safety Control Measures



A.   Ventilation

     1.   Laboratory ventilation is normally designed to provide 
	  eight air changes per hour.  This flow is not necessarily 
	  sufficient to prevent accumulation of chemical vapors.       
	  Laboratory work shall be conducted in a fume hood, glove 
	  box, or similar device when:

          a.   Procedures call for work with toxic substances 
	       which are volatile;  i.e., evaporate at normal 
	       temperature and pressure, or

          b.   There is a possibility the action level or PEL 
	       (see Appendix III) will be exceeded.

     2.   The protection provided by the laboratory fume hoods 
	  is dependent upon two important factors:

          a.   proper use of the hood, and

          b.   maintenance of adequate airflow through the hood.

     3.   The way the hood is used will determine the degree of 
	  protection it will provide.  Each employee is responsible 
	  for implementing the following work practices when           
	  using a hood.

          a.   Continually monitor air being drawn into the hood 
	       by attaching a kim wipe or light-weight strip of 
	       paper to the bottom of the sash.

          b.   Operate the hood at the proper sash position;  
	       i.e.,  maximum 12 inch sash height for hoods with 
	       vertical sliding (up and down) sashes and the        
	       sashes closed as much as possible for hoods with 
	       horizontal sliding (left and right) sashes.  This 
	       helps to ensure optimum protection when conducting 
	       operations in the hood.  A small sash opening maximizes 
	       air velocity through the hood face and may provide 
	       additional protection from unexpected splashes or 
	       chemical reactions. 

          c.   Avoid using the hood for storage of bottles and 
	       equipment, especially along the back wall.  Any 
	       apparatus that must be housed within the hood should 
	       fit completely inside the hood.  Elevate the apparatus 
	       on blocks (at least 2 inches off the benchtop) to 
	       allow air to flow freely around and beneath.
	  d.   Manipulations within the hood should be performed at 
	       least 6 inches inside the face of the hood or as far 
	       towards the back of the hood as possible.  This minimizes 
	       the possibility of contaminants escaping from the hood.

          e.   Fully close the hood sash and turn off the fan 
	       (if possible) when the hood is not in use.  The fan 
	       should remain on if volatile materials are being        
	       temporarily (i.e., for the duration of a current 
	       project) stored in the hood.

          f.   Things which cause air turbulence across the face of 
	       the hood such as fans, window air conditioning units, 
	       or excessive movement should be avoided.

          g.   Exhaust hoods do not provide adequate protection for 
	       all operations involving toxic materials.  A higher level 
	       of containment should be used for procedures where 
	       minor contamination can be serious.  If you are in 
	       doubt about the level of containment needed for
	       operation, ask your PI or contact the CHO.

     4.   EHSO conducts annual surveys of fume hoods to ensure 
	  adequate airflow is maintained through the hood face.  
	  Face velocities should be between 80 and 120 feet per 
	  minute (fpm).  Hoods that do not meet these minimum 
	  standards are considered "inadequate" and should not 
	  be used for protection from toxic or volatile materials.  
	  Contact EHSO at x65180 if you suspect the hood is not 
	  working properly.

     5.   At no time shall laboratory fume hood alarms be tampered 
	  with or disabled.  Upon activation of the alarm work within 
	  the hood should cease and facilities and/or the EHSO must 
	  be notified.  


The range and quantity of hazardous substances used in laboratories 
requires preplanning to respond safely to chemical spills.  The 
cleanup of a chemical spill should only be done by knowledgeable 
and experienced personnel.  Spill kits with instructions, adsorbents, 
reactants, and protective equipment should be available to clean up 
minor spills.  A minor spill is one that does not spread rapidly, 
does not endanger people or property except by direct contact, 
does not endanger the environment, and the laboratory staff is 
capable of handling safely without the assistance of safety and 
emergency personnel.  All other chemical spills are considered 
major and EHSO must be notified at x63202.  In the event of a 
minor spill the following procedures shall be carried out:

     1.   Attend to anyone who may have been contaminated or hurt.

     2.   Ensure that the fume hood(s) is on.  Open windows where 
	  possible to increase exhaust ventilation and if the spilled 
	  material is flammable, turn off all ignition and heat sources.

     3.   Secure cleanup supplies.  Neutralize acids and bases, if 
	  possible.  Ensure protective apparel is resistant to the 
	  spill material.

     4.   Control the spread of the liquid by containing the spill.

     5.   Absorb the liquid by adding appropriate absorbent materials 
	  from the spill's outer edges toward the center.  

     6.   Collect and contain the cleanup residues by scooping it into 
	  a plastic bucket or other appropriate container.

     7.   Properly dispose of the waste as hazardous waste.

     8.   Decontaminate the area and affected equipment.  Ventilating 
	  the spill area may be necessary. 

     9.   Document what happened, why, what was done, and what was 
	  learned.  Such documentation can be used to avoid similar 
	  instances in the future.  Major incidents are almost always 
	  preceded by numerous near misses.

In any event, there should be supplies and equipment on hand to deal 
with the spill, consistent with the hazards and quantities of the 
spilled substance.  These cleanup supplies should include neutralizing 
agents (such as sodium carbonate and sodium bisulfate) and absorbants 
(such as vermiculite and sand).  Paper towels and sponges may also be 
used as absorbent-type cleanup aids, although this should be done 
cautiously.  For example, paper towels used to clean up a spilled 
oxidizer may later ignite, and appropriate gloves should be worn 
when wiping up highly toxic material with paper towels.  Also, when 
a spilled flammable solvent is absorbed in vermiculite or sand, the
resultant solid is highly flammable and gives off flammable vapors 
and, thus, must be properly contained or removed to a safe place.  
If you have questions regarding spill clean up requirements please 
contact EHSO at x63198.

In the event of a major spill the following procedures shall be 
carried out:

     1.   Attend to anyone who may be hurt or contaminated if it 
	  can be accomplished without endangering yourself.
     2.   If flammable materials are spilled, de-energize 
	  electrical devices if can be done without endangering 

     3.   Call Campus Security at x66911.


Proper disposition of all hazardous materials used in laboratories 
is primarily the responsibility of the PI or researcher to whom a 
laboratory is assigned.  Safe disposition of hazardous materials 
is required whenever a PI or researcher leaves the University or 
transfers to a different laboratory.  The following procedures 
should be completed when a Principle Investigator or researcher 
leaves the University or transfers to a different laboratory.

     1.     Assure that all chemical containers are labeled with 
	    the name and hazard.   All containers must be securely 
	    closed.  Beakers, flasks, vials, evaporating dishes, etc. 
	    must be emptied and the contents properly disposed.  
	    Remember to check refrigerators, freezers, cold rooms, 
	    fume hoods, biological safety cabinets, bench tops, storage 
	    cabinets, stock rooms, etc.

One of the most problematic situations is the sharing of storage 
units such as refrigerators, freezers, cold rooms, stock rooms, etc., 
particularly if no one has been assigned to manage the space.  Shared 
spaces must be properly surveyed in order to locate and appropriately 
dispose/designate remaining chemicals.

     2.   Determine which chemicals are usable and transfer responsibility 
	  for these materials to another party who is willing to take 
	  charge of them.  If a new user cannot be found, the materials 
	  should be disposed.
     3.   Controlled substances must be disposed of as specified by the
	  DEA permit under which it is held.  Abandonment of a controlled 
	  substance is a violation of the Drug Enforcement Agency (DEA)
	  requirements.  Permission to transfer ownership of a 
	  controlled substance to another individual must be received 
	  from DEA.

     4.   Remove compressed gas cylinder connections, replace cylinder 
	  caps, and return cylinders to suppliers.  If cylinders are 
	  non-returnable, contact the Hazardous Materials Management 
	  Program at x63198.

     5.   If laboratory equipment will be left for the next occupant, 
	  clean or decontaminate it before departing the laboratory.
     6.   If laboratory equipment will be discarded, be aware that 
	  capacitors, transformers, mercury switches, mercury 
	  thermometers, radioactive sources and chemicals must       
	  be removed prior to disposal.  Contact the EHSO for assistance.

     7.   Wash off fume hood surfaces and bench tops.  

     8.   Prepare chemicals targeted for hazardous waste disposal by 
	  following procedures in Appendix VII.  This process should 
	  be started at least a month before departure from the 
	  laboratory to allow ample time to properly dispose all 
	  materials.  Hazardous waste pickup should be completed before 
	  the laboratory is vacated.  Contact the EHSO Hazardous Materials 
	  Management Program at x63198.

     9.   Notify the department Chair and the Chemical Hygiene Officer 
	  at x65180 when the laboratory has been cleared.