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Appendix
D: Health & Safety Design Considerations for Laboratories
For any new construction or renovation of laboratory areas, consider
health, safety and regulatory compliance issues early in the design stage
of the project. The following outlines some of these issues:
Layout (top)
- Laboratory space should be physically separate from personal desk
space, meeting space and eating areas. Workers should not have to go
through a laboratory space where hazardous materials are used in order
to exit from non-laboratory areas. Consider making visible separation
between lab and non-lab space, for instance with different flooring.
- Fire-rated hallway doors should have magnetic hold-open features,
such that the door will close in the event of an alarm.
- Doors to laboratories should not be fire-rated unless necessary.
- Entryways should have provisions for mounting emergency information
posters and other warning signage immediately outside the laboratory
(e.g., on the door).
- Each door from a hallway into a lab should have a view panel to prevent
accidents from opening the door into a person on the other side and
to allow individuals to see into the laboratory in case of an accident
or injury.
- Laboratory areas with autoclaves should have adequate room to allow
access to the autoclave and clearance behind it for maintenance. There
should also be adequate room for temporary storage of materials before
and after processing. Autoclave drainage should be designed to prevent
or minimize flooding and damage to the floor.
- For laboratories using radioactive materials:
- Eating and drinking areas should be physically separate and conveniently
located.
- Allow for security of laboratory and materials.
- Consider designing the lab to allow separation of radioactive materials
use from other laboratory activities.
Furniture
and Fixtures (top)
- Work surfaces should be chemical resistant, smooth, and readily cleanable,
such as chemical-grade Formica.
- Work surfaces, including computer areas, should incorporate ergonomic
features, such as adjustability, appropriate lighting and equipment
layout.
- Benchwork areas should have knee space to allow room for chairs
near fixed instruments, equipment or for procedures requiring prolonged
operation.
- Handwashing sinks for particularly hazardous chemicals or biological
agents may need elbow or electronic controls.
- Wet chemical laboratories and darkrooms should have solvent resistant
coved flooring using sheet goods rather than tile, particularly in areas
where fume hoods are located.
- Do not install more sinks or cupsinks than are necessary. Unused
sinks may develop dry traps, resulting in odor complaints.
- Sink faucets and hose bibs that are intended for use with attached
hoses are provided with back siphon prevention devices.
- Cabinets for chemical storage should be of solid, sturdy construction.
Hardwood or metal shelving is preferred. Some may require ventilation.
- Materials of construction should be carefully considered where corrosive
materials will be stored, e.g., corrosive-resistant liners or trays
on shelves, location away from copper fittings, etc.
- Allow space within the building for any central chemical and biological
or radioactive waste storage needs.
- Wall shelving should have heavy-duty brackets and standards and should
be attached to studs or solid blocking. For office spaces, bookcases
are preferable to wall-mounted shelving.
- Flammable liquid storage needs should be defined in advance so that
the laboratory may have space for a suitable number of flammable storage
cabinets. Per the Uniform Fire Code, quantities greater than 10 gallons
of flammable liquids must be stored in a flammable liquid storage cabinet,
unless safety cans are used. No more than 25 gallons of flammable liquids
in safety cans may be stored outside a flammable liquid storage cabinet.
- Flammable liquid storage is not allowed below grade or near a means
of egress, per the Uniform Fire Code.
- Flammable storage cabinets should not be vented unless there is a
significant odor or vapor control concern.
- Laboratories using corrosive liquids should have ample storage space
low to the floor, preferably in low cabinets, such as under fume hoods.
- Allow space for the variety of waste collection containers needed.
Depending on the laboratory, these may include laboratory trash, broken
glass, sharps, recyclable containers, used oil, medical waste, and/or
radioactive waste.
- Laboratories using compressed gases should have recessed areas for
cylinder storage and be equipped with devices to secure cylinders in
place.
- All laboratories should have storage space for supplies and combustible
materials, e.g., boxes of gloves, spill kits, boxes of centrifuge tubes,
etc.
Laboratory Ventilation (top)
- Laboratory ventilation rates should ensure 8-10 air changes per hour
minimum for occupied spaces and 6 air changes per hour minimum when
unoccupied.
- Bypass style fume hoods should be used. Auxiliary air hoods should
not be used.
- Fume hoods should have recessed work surfaces to control spills.
- The location of fume hoods, supply air vents, operable windows, laboratory
furniture and pedestrian traffic should encourage horizontal, laminar
flow of air into the face of the hood, perpendicular to the hood opening.
Hoods should be placed away from doors and not where they would face
each other across a narrow isle.
- Hoods must have a face velocity of 100-125 linear feet per minute
with the sash fully open or at its standard configuration (e.g., at
the stopper height).
- Each hood must have a continuous monitoring device, such as a magnehelic
gauge. The device should display either air velocity or static pressure,
rather than only an audible alarm.
- Supply air vents should be placed away from or directed away from
fume hoods to avoid interference. Air velocity caused by supply vents
should not exceed 25 feet per minute at the face of the hood.
- Noise from the fume hood should not exceed 65 dBA at the face of
the hood.
- Use hard ducting for the positive side of exhaust ducting for all
internal (penthouse) fans to prevent contaminant leakage into work areas.
- Fume hood exhaust ducts must not contain fire dampers.
- Unless otherwise specified (e.g., clean rooms), air pressure in the
laboratory should be negative with respect to the outer hallways and
non-laboratory areas.
- Consider the need for vented chemical storage areas or cabinets for
chemicals with low odor thresholds.
- Semi-conductor and other hazardous gases (e.g., silane, hydrogen
fluoride, chlorine, etc.) must be placed in vented gas cabinets
- Hoods for perchloric acid require stainless steel construction and
a wash-down system and a dedicated, isolated fan.
- Hoods requiring filters (such as those for some radioisotopes or
biological materials) should be designed and located such that filters
may be accessed and changed easily.
- Provisions should be made for local exhaust of instruments, gas cabinets,
vented storage cabinets or other operations requiring local ventilation.
- Single vertical sliding sashes are preferred over horizontal or split
sashes.
- Debris screens should be placed in the ductwork leading from the
hood.
Emergency Equipment (top)
- Laboratories using hazardous materials must have an eyewash and safety
shower within 100 feet or 10 seconds travel time from the chemical use
areas.
- Drench hoses support, but do not replace, safety showers and eyewashes.
- Eyewashes and safety showers should have plumbed drains.
- Eyewashes and safety showers should be standardized at least within
a laboratory building.
- Flooring under safety showers should be slip-resistant.
- Safety showers should have privacy curtains, particularly in large
laboratories or teaching laboratories.
- Fire extinguishers, safety showers and eyewashes should be conspicuously
labeled, particularly if recessed.
- Fire extinguishers appropriate for the chemicals and equipment in
use should be placed near the entrance of each laboratory, mechanical
and electrical room.
- Some chemical operations (e.g., distillation hoods) may benefit from
hood fire suppression systems.
- Windowless laboratories and environmental chambers should have emergency
lighting.
- Alarm enunciator panels should be descriptive of the area where the
alarm has activated.
Materials Handling (top)
- Loading docks should be equipped with dockboards and should have
enough room to maneuver pallets safely.
- Cryogenic liquid tanks should be placed in such a manner that their
controls could not accidentally be manipulated and such that they may
be secured to prevent unauthorized access.
- Cryogenic liquid tanks should be placed away from below grade areas
where dense vapors may collect and away from glass doors or windows.
- A phone should be placed near any loading area.
- Utility shut-off controls should be located outside the laboratory.
- Laboratories should have an abundant number of electrical supply
outlets to eliminate the need for extension cords and multi-plug adapters.
- Electrical panels should be placed in an accessible area not likely
to be obstructed.
- Ground fault circuit interrupters should be installed near sinks
and wet areas.
- Environmental chambers where evacuation or other alarms cannot be
heard should be equipped with strobe lighting or additional alarms.
- Central vacuum systems should not be used, since they are vulnerable
to contamination. Local vacuum pumps are preferable.
- All vacuum lines should have cold traps or filters to prevent contamination.
- Chilled water loops should be available for equipment in need of
cooling. Loops help to avoid excessive wastewater.
- Laser laboratories should have an emergency cut-off switch installed
near the entrance of the laboratory to turn off the laser remotely.
Many lasers require water-cooling systems requiring ground-fault circuit
interrupters.
- Laboratories using highly toxic gases should be equipped with alarmed
vapor sensors, preferably with automatic shutdown systems.
- Gas lines from highly toxic gases should use coaxial tubing for double
containment.
- Animal care and use areas must meet Association for Assessment and
Accreditation of Laboratory Animal Care International standards.
- Laboratories classified as Security Protection Level 2 (high value
equipment or security-sensitive materials) may require additional security
measures.
Established September 10, 1999 by Environmental Health and Safety. Contact
Robin Izzo at rmizzo@princeton.edu
or 258-6259 for any questions or concerns.
Health
and Safety Design Considerations
Project Checklist
Chemical,
Biological or Radioactive Material Use
 |
Chemical Type |
Consideration |
Section |
| |
General |
Solvent resistant coved flooring |
B |
| |
|
Possibly need ventilated storage |
C |
| |
|
Solid, sturdy shelving for storage |
C |
| |
|
Space for chemical waste storage |
C |
| |
|
Plumbed, conspicuously labeled eyewash and
safety shower within 100 feet or 10 second traveling distance |
E |
| |
|
Fire extinguishers mounted near entrance
of work or storage area and conspicuously labeled. |
E |
| |
Flammable Liquids |
More than 10 gallons in a lab needs flammable
liquid storage cabinet |
C |
| |
|
Storage not allowed below grade |
C |
| |
Corrosives |
Storage in low cabinets or shelves |
C |
| |
Perchloric Acid |
Stainless steel hood with washdown system |
D |
| |
Radioactive materials |
Physically separated eating and drinking
areas |
A |
| |
|
Separate radioactive material areas from
other areas |
A |
| |
|
Space for radioactive waste storage |
C |
| |
Biological Agents |
Handwashing sinks with elbow or electronic
controls |
B |
| |
|
Space for medical waste storage |
C |
| |
Highly Toxic Chemicals |
Handwashing sinks with elbow or electronic
controls |
B |
| |
Highly Toxic Gases |
Vented gas cabinet |
D |
| |
|
Coaxial tubing |
H |
| |
|
Alarmed vapor sensors |
H |
Equipment
 |
Equipment Type |
Consideration |
Section |
| |
Autoclave |
Adequate space for use, maintenance and materials
storage |
A
|
| |
|
Drainage to minimize flooding |
A
|
| |
Fume Hood |
Bypass style. No auxiliary air hoods. |
D
|
| |
|
Located to minimize cross-drafts and turbulence |
D
|
| |
|
Face velocity 100-125 linear feet per minute |
D
|
| |
|
Continuous monitoring device |
D
|
| |
|
No fire dampers in exhaust ducts |
D
|
| |
|
Debris screen |
D
|
| |
|
Single vertical sash |
D
|
| |
Distillation Hood |
Hood fire suppression system |
E
|
| |
Environmental Chamber |
Emergency lighting |
E
|
| |
|
Visual or audible local alarm if regular
alarm system cannot be heard inside the chamber |
F
|
| |
Cryogenic Liquid Tanks |
Controls secured or located to prevent accidental
opening |
F
|
| |
|
Not below grade or near glass doors or windows |
F
|
| |
Lasers |
Ground-fault circuit interrupters near water-cooling
systems |
G
|
| |
|
Consider use of chilled water loop |
G
|
| |
|
Carbon dioxide fire extinguishers, rather
than dry chemical extinguishers |
D
|
| |
|
Emergency cut-off switch at entrance |
G
|
| |
Equipment needing cooling |
Chilled water loops |
G
|
| |
Vacuum lines |
Local pumps preferred over central systems |
G
|
| |
|
Cold traps or filters to prevent contamination |
G
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