On a construction site, keeping cylinders on carts for extended periods of time may be more convenient but without modifications it's both a safety hazard and an OSHA violation.
Safety dictates that the carts used at a construction site should have a firewall installed between the two cylinders - - especially if one cylinder is oxygen and the other is acetylene. The reason to have a separation/firewall standard is to prevent the spread of fire and multicylinder explosions in the event that a single cylinder leaks and a fire begins. Both storage options - separation and firewall - usually will require an employer to set up a storage area some distance from the welding or cutting area.
In an explanation of its 1926.350(a)(10) standard, OSHA said that $quot;storage$quot; of gas cylinders is defined as $quot;when it is reasonably anticipated that gas will not be drawn from the cylinder within 24 hours (overnight hours included),$quot; and is based on the recognition that welding and cutting operations usually involve gas being drawn sporadically. A period of time shorter than 24 hours would mean that gas cylinders would have to be transported back and forth from work area to storage area.
Two construction companies in the state of New York were handed fines of more than $25,000 and $33,000 for violations that included improper storage of gas cylinders, in February 2005. Other sites have even been shut down. Unless a site manager can document that gas cylinders had been used in the previous 24 hours, it is better, and less costly, to ensure any carts holding gas cylinders on site meet the OSHA specifications.