Equipment and accessories (e.g., hoses, valves, fittings, sensors) should be labeled regarding their intended use and any limitations (e.g., Maximum Allowable Working Pressure). Chemicals (including gases) should be labeled and expiration dates (if applicable) identified. See Hydrogen Storage and Piping Systems section.

Incidents are more common when incompatible chemicals are mixed or when chemicals are stored/transferred using incompatible equipment. Personnel should ensure that labels are read and understood prior to mixing, dispensing, or transferring chemicals.