What happened? A small gas cylinder, of what was presumed to be, hydrogen chloride, was abandoned in an outside, departmental cylinder storage area (below left). The storage area (below center) borders a busy public thoroughfare, is directly adjacent to a building's fresh air intake and has very limited security – there is room for an agile person to climb over the top of the storage area fence (below right).
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The cylinder (below) had a handwritten label which read, "Was HCl - Empty Discard." The painted words "Matheson" and "Hydrogen …," were barely visible on the cylinder. Most all other written identification was obliterated. The cylinder was approximately 35 years old, based on the hydrostatic testing date stamp. The cylinder was capped but not plugged.
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The manufacturer was being contacted to try and verify the handwritten label using the cylinder serial number stamp which was still legible. If possible, the cylinder would be properly labeled and preferably returned to the manufacturer or disposed of as hazardous waste.
Why did it happen? Hydrogen chloride (HCl) (PDF format) is a toxic and corrosive gas. This cylinder, which was presumed to contain HCl, was not properly stored and was kept well beyond any reasonable compressed gas storage time and the label deteriorated. The owner was either not aware of proper hazardous chemical labeling requirements and how to handler toxic/corrosive gases or chose not to follow the required practices.
How can a similar occurrence be avoided? All hazardous chemicals must be properly labeled at all times, from the time they are brought into University facilities, to the time they are removed for disposal per Chemical Management Best Practices - Labeling/Identification. Gas cylinders must be labeled with the name of the gas, manufacturer and address and warning of the gas' main hazard (e.g. TOXIC, CORROSIVE).
Gas cylinders must be actively managed through periodic inspection and assessment to monitor the conditions under which they were stored, and the conditions of use and the continuing need for them and/or they must be depleted and disposed of within the time frame specified in the material safety data sheet (MSDS). The storage life of corrosive gases is very limited (HCl MSDS (PDF format) – "Use a first-in, first-out inventory system to prevent storing full cylinders for long periods").
Toxic/corrosive gas cylinders must be located in a specially configured fume hood, gas cabinet or exhausted and empty cylinders must be stored in the same manner as full cylinders. When transporting toxic/corrosive gases the protective cylinder cap must be in place and the valve outlet must be capped or plugged (see Minimum Requirements for Toxic/Corrosive Gas Use (PDF format) and Compressed Gas Disposal).
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