It's in the AGA-8 standard. According to Table 1: Ranges of Gas Mixture Characteristics Consistent with this Report  the expanded range for Gross Heating Value is 0 to 1800 BTU/scf
(where scf = standard cubic feet = ft3).

reference: AGA Report No. 8, Second edition, November 1992.

Julkaistu: Schneider Electric Suomi