1.  These regulations may be cited as the Dark Smoke (Permitted Periods) (Vessels) Regulations, 1958, and shall come into operation on the 1st day of June, 1958.

2.  The Interpretation Act, 1889, applies to the interpretation of these regulations as it applies to the interpretation of an Act of Parliament.

3.—(1) Emissions of dark smoke from a chimney of a vessel for not longer than the period specified in column (2) of the schedule to these regulations in respect of the class of case specified in column (1) shall be left out of account for the purposes of section 1 of the Clean Air Act, 1956:

Provided that—

(a)continuous emissions of dark smoke caused otherwise than by the soot blowing of a water tube boiler shall not exceed

(i)in the case of classes 1 and 2, 4 minutes;

(ii)in the case of natural draught oil-fired boiler furnaces in class 4, 10 minutes; and

(b)in no case shall black smoke be emitted for more than 3 minutes in the aggregate in any period of 30 minutes.

In this paragraph “black smoke” means smoke which, if compared in the appropriate manner with a chart of the type known at the date of the passing of the Clean Air Act, 1956, as the Ringelmann Chart, would appear to be as dark as or darker than shade 4 on the chart.

(2) For the purposes of the said schedule a vessel is not under way when it is at anchor or made fast to the shore or bottom, and a vessel which is aground shall be deemed to be under way.

SCHEDULE

EXPLANATORY NOTE

Section 1 of the Clean Air Act, 1956, as applied by section 20 of that Act, makes it an offence to emit dark smoke (as defined) from the chimney of a vessel, but provides that emissions of smoke lasting for not longer than such periods as may be specified by the Minister of Housing and Local Government by Regulations shall, in such classes of case and subject to such limitations as may be so specified, be left out of account for the purposes of the section. These Regulations specify the permitted emissions of smoke.