Section 172.185 - Permeability of spaces(a) When doing the calculations required in § 172.170 , the permeability of a floodable space other than a machinery space must be as listed in Table 172.060(b).(b) Calculations in which a machinery space is treated as a floodable space must be based on an assumed machinery space permeability of 85%, unless the use of an assumed permeability of less than 85% is justified in detail.(c) If a cargo tank would be penetrated under the assumed damage, the cargo tank must be assumed to lose all cargo and refill with salt water up to the level of the tankship's final equilibrium waterline.