(1) Before welding, cutting or heating is commenced on any surface covered by a preservative coating whose flammability is not known, a test must be made by a competent person to determine its flammability. Preservative coatings must be considered to be highly flammable when scrapings burn with extreme rapidity.

(2) Precautions must be taken to prevent ignition of highly flammable hardened preservative coatings. When coatings are determined to be highly flammable they must be stripped from the area to be heated to prevent ignition. A 1 1/2-inch or larger fire hose with fog nozzle, which has been uncoiled and placed under pressure, must be immediately available for instant use in the immediate vicinity, consistent with avoiding freezing of the hose.

(3) Protection against toxic preservative coatings.

(a) In enclosed spaces all surfaces covered with toxic preservatives shall be stripped of all toxic coatings for a distance of at least 4 inches from the area of heat application or the employees must be protected by air line respirators meeting the requirements of chapter 296-842 WAC, Respirators.

(b) In the open air employees must be protected by a filter type respirator in accordance with the requirements of chapter 296-842 WAC, Respirators.

(4) Before welding, cutting or heating is commenced in enclosed spaces on metals covered by soft and greasy preservatives, the following precautions must be taken:

(a) A competent person must test the atmosphere in the space to ensure that it does not contain explosive vapors, since there is a possibility that some soft and greasy preservatives may have flash points below temperatures which may be expected to occur naturally. If such vapors are determined to be present, no hot work must be commenced until such precautions have been taken that will ensure the welding, cutting or heating can be performed in safety.

(b) The preservative coatings must be removed for a sufficient distance from the area to be heated to ensure that the temperature of the unstripped metal will not be appreciably raised. Artificial cooling of the metal surrounding the heated area may be used to limit the size of the area required to be cleaned. The prohibition contained in WAC 296-304-03005 (2)(b) must apply.

(5) Immediately after welding, cutting or heating is commenced in enclosed spaces on metal covered by soft and greasy preservatives, and at frequent intervals thereafter, a competent person must make tests to ensure that no flammable vapors are being produced by the coatings. If such vapors are determined to be present, the operation must be stopped immediately and must not be resumed until such additional precautions have been taken as are necessary to ensure that the operation can be resumed safely.