OSHA general industry standard 29 CFR 1910.253 (b)(4)(iii) reads as follows, "Oxygen cylinders in storage shall be separated from fuel-gas cylinders or combustible materials (especially oil or grease), a minimum distance of 20 feet (6.1 m) or by a noncombustible barrier at least 5 feet (1.5 m) high having a fire-resistance rating of at least one-half hour."
This standard raises the question, is an oxygen cylinder and an acetylene cylinder left on a welding/cutting cart considered in storage and subject to the storage requirements in 1910.253(b)(4)(iii)? In other words, are the cylinders required to be removed from the cart and put into proper storage or are the cylinders required to be on a cylinder cart with a firewall that meets the minimum height and fire-resistance rating requirements?
The answer to each of these questions is no. In general industry, OSHA will consider a single acetylene cylinder and a single oxygen cylinder on a cylinder cart to be "in use" or "ready to use" and not subject to the general industry cylinder storage provisions regardless of when gas will next be withdrawn from the unit.
However, for the cylinders to be left on the cart indefinitely, the following condition must be met to exempt general industry employers from the storage requirements in 1910.253(b)(4)(iii).
1. No more than a single acetylene cylinder and a single oxygen cylinder are on a cylinder cart. The cylinder cart must be specifically designed to hold/carry oxygen and acetylene cylinders in the upright position. The cylinders must be securely held to the cart (such as by straps, chains or other securing device).
2. The cart is on a firm, level surface.
3. The cart is not in an area where there is a reasonably foreseeable risk of being struck by vehicles, equipment, or material.
4. Both cylinders either have valves closed with protection caps on or are connected to a properly functioning regulator.
Keep in mind that OSHA standards are considered minimum requirements. If you want to go a step further to ensure a safer workplace you can use a firewall cylinder cart for your welding/cutting units. If you question whether you can always meet the four conditions described above, you should consider using firewall cylin