6.2 Confined space an enclosed or partially enclosed space which:
(a) is at atmospheric pressure during occupancy;
(b ) is not intended or designed primarily as a place of work;
(c )may have restricted means for entry and exit; and
(d) may -
(i) have an atmosphere which contains potentially harmful levels of contaminant;
(ii) not have a safe oxygen level; or
(iii) cause engulfment.
Confined spaces include but are not limited to -
(A) storage tanks, tank cars, process vessels, boilers, pressure vessels, silos and other tank-like compartments;
(b ) open-topped spaces such as pits or degreasers;
(c )pipes, sewers, shafts, ducts and similar structures; and
(D) any shipboard spaces entered through a small hatchway or access point, cargo tanks, cellular double bottom
tanks, duct keels, ballast and oil tanks, and void spaces, but not including dry cargo holds.