Refrigeration safety

Fig. 3. Refrigerant safety group classifications estabUshedby ANSI/ASHRAE 34-1992 (2). See text.

This standard provides an unambiguous system for numbering refrigerants and assigning composition-designating prefixes for refrigerants. Safety classifications based on toxicity and flammability data are included. [from Section... 

See Figure 11-23 for a diagram of refrigerant safety group classification. The manufacture and use of some specific refrigerants have been canceled and/or restricted due to the detrimental effect on the ozone layer. 

Figure 11-23. Refrigerant safety group classification, per ANSI/ASHRAE Standard 34-1992, also see Table 11-3B. Used by permission ANSI/ASHRAE Standard 34-1992 including Addenda 34a-o and 34q-x, p. 5, 1992, 1996. American Society of Heating, Refrigerating, and Air Conditioning Engineers, Inc. All rights reserved.

BS 4434 1980 Refrigeration safety, British Standards Institntion, Milton Keynes... 

There is more to a laboratory than work benches and the instruments mounted on them. Free-standing equipment must also be considered. This includes refrigerators, safety storage cabinets for chemicals, safety shower, desk space, typewriter stand or computer terminal, or any other equipment that is not bench-mounted. File cabinets, which are real space-robbers, must not be forgotten. In one laboratory, much space was saved by placing two-drawer file cabinets beneath the large table used for sorting samples. 

Gradually all things that are to go into the laboratory, such as work benches, refrigerators, safety storage cabinets, floor-mounted equipment, desks, file cabinets, balance tables, and a myriad of other items, are in place. Now is another good time to check on traffic patterns. Will a piece of equipment stick out too far Will a desk chair cause obstruction Will the refrigerator door cause problems when open These are just a few of the questions that should be asked again. 

To carry out its mission, CPSC administers five statutes. They are (1) the Consumer Product Safety Act (CPSA), (2) the Federal Hazardous Substances Act (FHSA), (3) the Flammable Fabrics Act (FFA), (4) the Poison Prevention Packaging Act (PPPA), and (5) the Refrigerator Safety Act (RSA). Toxicological issues arise most frequently under the CPSA, FHSA, and PPPA. CPSC regulations implementing these statutes may be found at Title 16 of the Code of Federal Regulations (CFR) and are available on the Commission s website. 

Piping and plumbing -Control -Electrical -Refrigeration -Safety systems -Habitable environment -Emissions control -Bunkering and storage -Diagnostics systems -Maintenance systems... 

The third type of storage for anhydrous ammonia is pressurized storage without refrigeration. This is used at small terminals, ia some transport vehicles, and ia field appHcation equipment. For safety reasons, maximum allowable storage pressure ia vessels at retail locations and ia the field has been set at 1.83 MPa (265 psig) (8). This pressure is sufficient to prevent boiling at temperatures up to 46°C. Safety pop-off valves are provided to vent ammonia should higher temperatures be encountered. 

Anhydrous ammonia is moved worldwide ia specially designed vessels, barges, rail cars, and tmcks. AH modes are covered by rigid safety restrictions (8). Ships and barges usuaHy employ refrigeration or semirefrigeration to maintain the Hquid, while rail cars and tmcks normally depend only on pressure... 

The decomposition kinetics of an organic peroxide, as judged by 10-h HLT, largely determines the suitabiUty of a particular peroxide initiator in an end use appHcation (22). Other important factors ate melting point, solubiUty, cost, safety, efficiency, necessity for refrigerated storage and shipment, compatibihty with production systems, effects on the finished product, and potential for activation. 

Safety in Refrigeration Systems This is of paramount importance and should be considered at every stage of installation. 

AMD 1 Specification for safety and environmental aspects m the design, construction and installation of refrigerating appliances and systems (AMD 9383) dated 15 March 1997. Supersedes BS 4434 1989... 

All rail tank cars must be equipped with roller bearing wheels. Using a container designed for the maximum pressure that the contents can generate from ambient conditions will eliminate the need for refrigeration of the container for safety. Overpackaging can be used to provide maximum protection for example, use DOT Specification 105 tank cars instead of general purpose cars. 

MarshaU, J., A. Mundt, M. Hult, T. C. McKealvy, P. Myers, and J. Sawyer (1995). The Relative Risk of Pressurized and Refrigerated Storage for Six Chemicals." Process Safety Progress 14, 3 (July), 200-211. 

Elsworth, J., J. Eyre, and D. Wayne. 1983. Combustion of refrigerated liquefied propane in partially confined spaces, Int. Sym. Loss Prevention and Safety Promotion in the Process Industries. Harrogate (UK), IChemE Symp. Series No. 81. pp. C35-C48. 

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