ment should be discussed regarding any unique noise or vibration sensitivity in order to locate the equipment properly.

TABLE 9.2 Examples of Equipment That Can Be Shared Between Researchers and Research Groups


Balances

Centrifuges


Gas chromatographs

High-performance liquid chromatographs

Ice machines

Incubators

Mass spectrometers

NMRs

Ovens

pH meters

Refrigerators/freezers

Weigh enclosures


Large equipment such as centrifuges, shakers, and water baths often work best in separate equipment rooms. Pumps for older mass spectrometer units are both hot and noisy and are often located in either a small room or a hall. If in a closet, the area must have extra exhaust to remove heat, or else equipment may fail from overheating. With smaller and newer mass spectrometers, the pumps are often small and can fit into cabinets specifically designed for them. These pumps work especially well when water cooling is not required. Very few researchers need to hear their instrumentation running, but many want to see the equipment.

Another consideration crucial to equipment-intensive areas is the allowable vibration tolerance. Most analytical equipment such as NMRs, sensitive microscopes, mass spectrometers, and equipment utilizing light amplification (laser) require either vibration isolation tables or an area that is structurally designed to allow for very little vibration. Clarify the tolerance requirements with the user and equipment manufacturer during the equipment-programming phase, or early design process, so that the appropriate structure can be designed and the construction cost can be estimated more accurately.

9.B.7 Safety Equipment and Utilities

Each laboratory should have an adequate number and placement of safety showers, eyewash units, and fire extinguishers for its operations. (See Chapter 6, section 6.C.10, for more information.) The American National Standards Institute (ANSI) Z358.1-2004 standard provides guidance for safety shower and eyewash installation. The 2004 version recommends provision of tepid water, which can be complicated from an engineering standpoint. Although this standard does not address wastewater, most designers agree that emergency eyewash and shower units should be connected to drain piping. It is prudent to have floor drains near the units, preferably sloped to the drain to prevent excessive flooding and potential slip hazards. Consider choosing barrier-free safety showers and eyewash units that can accommodate individuals with disabilities. The maximum reach height for the activation control for safety showers is 48 in.

Sprinkler systems may be required by the building code and are almost always recommended. For areas with water-sensitive equipment or materials, consider preaction systems. Most dry or alternative systems do not function in a laboratory environment with chemical hoods and other ventilation. There may be resistance to the idea of installing sprinkler systems in laboratories, particularly laboratories that use water-sensitive chemicals or equipment. The following facts may be helpful:

   Each sprinkler head is individually and directly activated by the heat of the fire, not by smoke or an alarm system. Thus, small fires are not likely to activate the sprinkler and moderate-size fires will likely activate only one or two heads. Indeed, more than 95% of fires are extinguished by one or two sprinkler heads.

   Statistics show that the sprinkler head failure rate is 1 in 16 million.

   In the event that the water from the sprinkler system reacts with water-sensitive materials, ensuing fires would be quenched once the reaction stopped. Damage is likely to be less severe than if a fire was not suppressed and was allowed to reach other flammable or combustible materials in the laboratory.

   Laboratory equipment, including lasers, is just as likely to be harmed by the fire as by the water. Without the sprinkler system, a fire that is large enough to activate the sprinkler system would result in response by the fire department. The sprinkler heads are designed to release water at a rate of 10–15 gallons per minute (gpm), whereas a firefighter’s hose delivers 250–500 gpm.

   Dry chemical systems can seriously damage electronic and other laboratory equipment and are impractical in a building-wide system. Alternative agents are impractical because of the amount of space required for the cylinders and are most effective in rooms or areas that are sealed, which is not how laboratories are designed. These systems are most practical for an individual application, such as a piece of equipment or a “sealed” room.

   Locate utility shutoff switches outside or at the exit of the laboratory. The purpose of the switch is to shut down potentially hazardous operations quickly in the event of an emergency.

   Locate room purge buttons at the exits in laboratories with chemical hoods. For most laboratory buildings, activating the room purge button shuts down or minimizes supply air while increasing exhaust ventilation. In the event of a chemical spill, activating the purge system will help ventilate the resulting chemical vapors more quickly.

   Laboratories should have abundant electrical supply outlets to eliminate the need for extension cords and multiplug adapters. Place electrical panels in an accessible area not likely to be ob-



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