PART V PRECAUTIONS AGAINST ASPHYXIATION, INJURIOUS FUMES OR EXPLOSIONS

66 Exceptions from Regulations 59 and 63
1 The provisions of paragraphs (1) (c) and (1) (d) of Regulation 59 as to naked light certificates and the provisions of Regulation 63 as to the cleaning and ventilation of oil-tanks, shall not apply in the case of minor repairs to be carried out—
(a) to the outer surface of an oil-tank on board or in a vessel; or
(b) in or to the outer surface of any compartment or space adjacent to any such oil-tank,
in cases where the only oil last carried was oil having a flash point of one hundred and fifty degrees Fahrenheit or above (Pensky-Martens closed test):
Provided that adequate areas of the interior and exterior surfaces of the oil-tank or, as the case may be, of the compartment or space adjacent thereto, in the immediate neighbourhood of the part to be repaired shall be freed from oil or sludge; so, however, that as respects repairs to be carried out to the outer surface of an oil-tank below the level of any oil in that tank only the exterior surface of that oil-tank need be so freed.
In every case to which this paragraph applies appropriate special precautions shall be taken for preventing and extinguishing fire.
2 The provisions of paragraphs (1) (a) and (1) (b) (iii) of Regulation 59 as to naked light certificates shall not apply in the case of minor repairs involving the application of a naked light to the outer surface only of the hull of a tanker in which the only oil last carried as cargo was liquid methane, liquid propane or liquid butane, being liquid methane, liquid propane or liquid butane at atmospheric pressure, provided that a naked light certificate has previously been obtained on the same day and is in force in respect of the space between the hull and any oil-tank on board, and the space is adequately and continuously ventilated by mechanical means so as to ensure that an inflammable concentration of gas or vapour cannot be formed in it during the period for which the naked light certificate is in force.
3 The provisions of paragraph (1) (a) of Regulation 59 shall not apply to any part of a tanker where naked lights were allowed when the vessel was in service afloat:
Provided that the said paragraph (1) (a) shall apply whilst any oil-tank in the tanker is open except an oil-tank in respect of which a naked light certificate is in force.
4 The provisions of paragraph (1) (a) of Regulation 59 shall not apply in the case of tankers in which the only oil last carried was oil used for the purpose of a basin trial or a trial trip.