Portable tanks defined

As defined in NFPA 30 portable tanks have capacities above 60 gallons (227 L) and usually below 660 gallons (2498 L). 

Hazardous substances, as defined in 49 CFR 171.8, transported in cargo tanks, portable tanks, or hopper-type vehicles with capacities in excess of 3,500 water gallons, or in bulk explosives Division 1,1,... 

DOT defines a portable tank as any package over 110 gallon capacity and designed primarily to be loaded into or on, or temporarily attached to, a transport vehicle or ship. DOT Specification 51 covers welded or seamless steel... 

A portable tank is defined by TC and DOT as any packaging, except a cylinder having a 1000-lb (454-kg) or less water capacity, over 110 U.S. gallons (380 L) capacity and designed primarily to be loaded into or on, or temporarily attached to, a transport vehicle or ship. A portable tank is equipped with skids, mounting, or accessories to facilitate handling of the tank by mechanical means. As defined, a portable tank is not a cargo... 

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