§ Mr. Alfred Morrisasked the Minister of Housing and Local Government what tests he uses, and what standard he applies, in deciding whether a solid manufactured fuel should be declared an authorised fuel for the purposes of the Clean Air Act, 1956.
§ Mr. MellishIt has hitherto been necessary, in the absence of any recognised test or standard, to applyad hoc tests to ensure that fuels were substantially smokeless. After consulting the Clean Air Council, my right hon. Friend has decided to adopt the British Standards Institution's method of measuring smoke from manufactured solid fuels for domestic open fires, set out in B.S. 3841: 1965, and to accept the standard of smokelessness recommended by the Institution. This is that the smoke emission, measured by the 135W British Standards method, should not exceed 5 grammes of smoke per hour, i.e. about 20 per cent. of the amount of smoke emitted by bituminous coal under the same conditions. All the manufactured solid smokeless fuels which have so far been authorised comply with this standard.