edward t:

I cannot answer the specific questions as I do not have copies of ANSI/NFPA 505 or ANSI/NFPA 58. ANSI/NFPA does not have free access to their materials like ITSDF does. The best I can do at this time is to provide a possible source for these materials.

I do not know the specific reason why Siegal Gas and Oil Corp. indicates that the tanks should be removed prior to filling. I figure, however, that LPG is there business, they know the regulations, they know the safety implications and I am not about to challenge them.

In your statement of 80% full and using a scale, wouldn't one have to remove the tank to weigh it?