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.
| 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 |
| 1 Whichever results in the more disabling condition. | |
| 2 If tanks are partially filled, the permeability must be determined from the actual density and amount of liquid carried. | |