# Gas Safety (Management) Regulations 1996, Paragraph 1

Extent: E+W+S

In this Schedule—
“bar” means bars (absolute);
“barg” means bars (gauge);
“C” means degrees Celsius;
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“gross calorific value” means the gross calorific value, expressed in MJ/ m3, of a dry gas determined on the basis that the water produced by combustion is assumed to be condensed;
“mg/m3” means milligrams per cubic metre under the reference conditions;
“MJ/m3” means megajoules per cubic metre under the reference conditions;
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“relative density” (“RD”) means the ratio of VG to VA (expressed in the same units) where—
VG is the mass of a volume of the gas when containing no water vapour under the reference conditions; and
VA is the mass of the same volume of air containing no water vapour under those conditions;
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“WN” means the Wobbe Number of the gas, which is calculated in accordance with the following formula—
gross calorific value÷relative density
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Source: https://www.legislation.gov.uk/uksi/1996/551/schedule/3/part/III/paragraph/1 (the official version)
Page: https://openlegislation.uk/gas-safety-management-regulations-1996/schedule-3/part-III/paragraph-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.