CHAPTER 7

GENERAL LABORATORY SAFETY

5.0 LABORATORY DESIGN

 

5.1  Overall Design Considerations

5.2  Walls and Ceilings

5.3  Floors

5.4  Work Surfaces

5.5  Furniture & Fittings

5.6  Electrical System

5.7  Fire Protection

5.8  Ventilation

5.9  Gas Cylinders


Dangers associated with research or clinical lab work can be minimized by proper laboratory design.  This section contains information about good laboratory design. Researchers or laboratory supervisors may find this information useful if they are:

         Relocating furniture and equipment within the laboratory;

         Collaborating with Facilities Planning to build or remodel a new or existing laboratory.

 

5.1       Overall Design Considerations

Good laboratory design should provide for:

         containment and separation of various potential hazards

         ability to clean

         ventilation and drainage systems

         storage for hazardous agents and equipment

         fire protection including sprinklers and emergency exits

         emergency response

         control of access

         support rooms outside the laboratory (e.g., offices, eating areas)

         properly located emergency showers and eyewashes

         clothing changing rooms

         personnel space (ideally 50 square feet per person)

         shielding or sterilizing facilities

         proper storage for water disposal

 

In a clinical laboratory, it may be necessary to provide areas for:

         dosage administration

         blood drawing

         patient waiting areas

 

5.2       Walls and Ceilings

Walls and ceilings should be smooth and impervious.  This will result in easier cleaning and decontamination of the facility, if necessary.  Walls and ceilings should have low flame spread. 

 

5.3       Floors

Floors should not flex under loads.  Spills should be contained (i.e., floors should be sealed or there should be a controlled floor drain).

 

5.4       Work Surfaces

Work surfaces should meet the following requirements:

         non-asbestos containing material

         hard solid surface

         scratch resistant

         of  low porosity

         heat, cold, chemical and stain resistant

         easy to clean and decontaminate

         continuous (i.e., as few seams as possible)

 

5.5       Furniture & Fittings

Furniture and fittings should be designed and constructed so that:

         any contamination can be easily removed;

         furniture must have durable impermeable coverings ,( i.e., vinyl not cloth).

         evacuation of the lab is not impeded in case of emergency;

         a sink is available specifically for hand washing

 

5.6       Electrical System

The electrical power main switch cut off should be labeled and located near the exit.  This switch should operate independently of the lighting system.

 

5.7       Fire Protection

Laboratories should be designed to minimize the potential for fires.   Should a fire occur, there should be a capability to limit its size and prevent the fire from spreading (e.g., self-closing fire doors).  As indicated earlier, there should be a means of safe exit for personnel.  An adequate supply of fire extinguishers should be provided as part of the design

Flammable storage cabinets are generally required whenever 1 liter of flammable per 100 square feet may be exceeded.  Contact EHS/Biological and Chemical Safety for additional information on flammable storage cabinets (extension 21781).

 

5.8       Ventilation

The method of ventilation in a laboratory depends on the toxicity of the substances and the nature of the experimental work being performed in the lab.  General ventilation is generally sufficient for low hazard/odor work.  The purpose of local exhaust ventilation systems is to capture hazardous and/or odiferous contaminants near their point of origin before they disperse into the laboratory.  Laboratories are to be under slightly negative pressure (~-0.1 w.g.) relative to adjacent areas.  This reduces the possibility of contaminants escaping into the hallway or other work areas.  For more information on laboratory ventilation specifications, contact EHS/B&C at 21781.

 

5.9       Gas Cylinders

Ideally, all gas cylinder stations should be located outside the building and gases should be piped into the point of use.  However, if they are brought inside the building, they must be secured when in use or being stored (See Section 3, Gas Cylinders).