Here are the answers:
1.) WHEN MUST THEY BE IN-STORAGE?
If you reasonably expect to use the oxy-acetylene within a 24-hour period, then you can leave them on the cart and it is considered to be “in-use”. Of course, they must be maintained in good condition, secured, upright, out of the way of vehicle traffic, etc.
2.) WHAT DOES STORAGE LOOK LIKE?
But, if you shut down for Sundays, for example, then you must put the cylinders “in-storage”. This means that the cylinders must be separated by at least 20-ft or have a 5-ft high fire wall separating them if they are closer than 20 feet apart.
Many companies still don’t do anything. As one of my students put it, “We change them out when they are empty!” So, I looked a little further into this issue and I found a letter of interpretation thanks to some help from the Compliance Assistance Specialists in my region. Click here to read the full letter. Otherwise, below I have pasted in a portion of it. Basically, as long as you are careful to fulfill 4 things, OSHA will consider it a “de minimus” violation and will not cite it. Read below:
Whether failure to comply with those storage requirements for single acetylene and oxygen cylinders on welding carts(1) or secured to substantial vertical surfaces should be considered de minimis(2) and not be cited.
The Agency has conducted an extensive review of the application of the storage requirements in construction to situations where there are only two cylinders on a cylinder cart or where the cylinders are secured to a wall or other substantial vertical surface.(3) The Agency has determined that, under §1926.350(a)(10), failure to comply with the storage requirements with respect to a single acetylene and a single oxygen cylinder on a cylinder cart would be considered a de minimis violation where all of the following parameters are met:
(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 materials (such as in a pathway for vehicles on a construction site).
(4) Both cylinders either have valves closed with protection caps on or are connected to a properly functioning regulator.