Safety gas cylinders

Always fasten cylinders to the lab bench with safety straps. A common type of gas cylinder safety strap is shown in Figure 20-6. The holder is screw clamped to the bench top and the cylinder is then strapped to it. 

Figure 20-6. Gas Cylinder Safety brackets. Left Bench mount. Right Wall mount.

C-14 Procedures for Testing of DOT Cylinder Pressure Relief Device Systems. Describes a new set of test procedures and apparatus for fire testing compressed gas cylinder safety (pressure) relief devices as required by DOT regulation, 49 CFR, Section 173.34(d). The procedures are applicable for cylinders which are less than 500 lbs. internal water volume and are designed to provide a means of testing to DOT requirements anywhere, with reliable test data and repeatable test results. Previous edition cited in 49 CFR (13 pages). 

Cylinder Safety If you plan to use compressed gas cylinders, safety should be a primary concern. A typical cylinder for analytical instruments has a pressure of 2000-3000 psig (140-210 bar) on delivery. A rupture at a cylinder valve causes rapid depressurization and can cause serious injury or structural damage to a lab (15). 

Compressed gas cylinders are used in gas welding. Except for the two cylinders on the welding cart, the oxygen and gas cylinders must be stored in separate areas. See chapter 2 for compressed gas cylinder safety. 

GAS CYLINDER SAFETY AND STAMPED MARKINGS Thomas J. Bruno and Paris D. N. Svoronos... 

Figure 15.4 shows a procedure for the refilling of returnable containers with a chemical of assured quality. (This will require some combination of documentation, sampling and analysis to ensure that the chemical is of the correct type, and in the intended condition.) This is applicable to drums and plastic containers, and bottles, but some modifications are necessary for pressure systems, i.e. gas cylinders, covered by the Pressure Systems Safety Regulations 2000 including ... 

The colors purple, brown, black, and gray have not been assigned a safety connotation. Specific color codes are also employed in the identification of alarms panel indicators, piping, compressed gas cylinders, electrical wiring, fire sprinkler temperature ratings, etc. Although these sometimes do not correspond with similar meanings. 

The sources of acetylene, nitrous oxide, and sometimes air are usually steel cylinders of the compressed gases purchased from specialty gas or welders gas suppliers. Thus, several compressed gas cylinders are usually found next to atomic absorption instrumentation and the analyst becomes involved in replacing empty cylinders with full ones periodically. Safety issues relating to storage, transportation, and use of these cylinders will be addressed in Section 9.3.7. The acetylene required for atomic absorption is a purer grade of acetylene than that which welders use. 

Phosgene is a highly toxic gas. All safety precautions must he followed during its preparation and handling. It is stored and shipped in leak-free steel cylinders in the complete absence of any water (or moisture). 

Steere, N. V. Ed., 1971, Handbook of Laboratory Safety, The Chemical Rubber Co. Press, Cleveland. Contains a chapter on compressed gas cylinders and cylinder regulators. 

The first level of safety for quality and control is the construction of compressed gas cylinders. The specifications for their construction in North America is defined by Department of Transportation (DOT) and Canadian Transport Commission (CTC) regulations. Cylinders are made from carbon steel or alloy steel with seamless, brazed, or welded tubing that is formed by billeting (drawing flat... 

Figure 11.22 on the next page shows a typical compressed gas cylinder. You can see that it is built to withstand high pressures. There are other safety precautions as well, however. 

The ballast bulb must be taped to prevent flying glass fragments in the unlikely event of breakage. Safety glasses should be worn for all laboratory work. Gas cylinders must be chained securely to the wall or laboratory bench (see pp. 644-646 and Appendix C). Liquid nitrogen must be handled properly (see Appendix C). 

Warning Never connect a gas cylinder directly to a closed system that is not specially designed to withstand high pressures (such as a combustion bomb for heats of combustion). Even when a regulator is used, remember that the diaphragm valve may slowly leak arrange for some kind of safety pressure release, if only a rubber tubing connection that can be easily blown off. 

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