Permeability of spaces.

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§ 174.090 Permeability of spaces.

When doing the calculations required in § 174.065 -

(a) The permeability of a floodable space, other than a machinery space, must be as listed in Table 174.090; and

(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.

Expand Table

Table 174.090 - Permeability

Spaces and tanks Permeability (percent)
Storeroom spaces 60.
Accommodation spaces 95.
Voids 95.
Consumable liquid tanks 95 or 0.1
Other liquid tanks 95 or 0.2


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