40 CFR Appendix Table 30 to Subpart G of Part 63 - Table 30 to Subpart G of Part 63—Roof Fitting Loss Factors, KFa, KFb, and m, a and Typical Number of Fittings, NT

Table 30 to Subpart G of Part 63—Roof Fitting Loss Factors, KFa, KFb, and m, a and Typical Number of Fittings, NT
Fitting type and construction details Loss factors b Typical number of fittings, NT
KFa (lb-mole/yr) KFb (lb-mole/[mi/hr] m-yr) m (dimensionless)
Access hatch (24-in-diameter well) 1.
Bolted cover, gasketed 0 0 c 0
Unbolted cover, ungasketed 2.7 7.1 1.0
Unbolted cover, gasketed 2.9 0.41 1.0
Unslotted guide-pole well (8-in-diameter unslotted pole, 21-in-diameter well) 1.
Ungasketed sliding cover 0 67 c 0.98
Gasketed sliding cover 0 3.0 1.4
Slotted guide-pole/sample well (8-in-diameter unslotted pole, 21-in-diameter well) ( d).
Ungasketed sliding cover, without float 0 310 1.2
Ungasketed sliding cover, with float 0 29 2.0
Gasketed sliding cover, without float 0 260 1.2
Gasketed sliding cover, with float 0 8.5 1.4
Gauge-float well (20-inch diameter) 1.
Unbolted cover, ungasketed 2.3 5.9 c 1.0
Unbolted cover, gasketed 2.4 0.34 1.0
Bolted cover, gasketed 0 0 0
Gauge-hatch/sample well (8-inch diameter) 1.
Weighted mechanical actuation, gasketed 0.95 0.14 c 1.0
Weighted mechanical actuation, ungasketed 0.91 2.4 1.0
Vacuum breaker (10-in-diameter well) NF6 (Table 31).
Weighted mechanical actuation, gasketed 1.2 0.17 c 1.0
Weighted mechanical actuation, ungasketed 1.2 3.0 1.0
Roof drain (3-in-diameter) NF7 (Table 31).
Open 0 7.0 e 1.4 NF8 (Table 32 f).
90 percent closed 0.51 0.81 1.0
Roof leg (3-in-diameter) NF8 (Table 32 f).
Adjustable, pontoon area 1.5 0.20 c 1.0
Adjustable, center area 0.25 0.067 c 1.0
Adjustable, double-deck roofs 0.25 0.067 1.0
Fixed 0 0 0
Roof leg (2 1/2-in-diameter) NF8 (Table 32 f).
Adjustable, pontoon area 1.7 0 0
Adjustable, center area 0.41 0 0
Adjustable, double-deck roofs 0.41 0 0
Fixed 0 0 0
Rim vent (6-in-diameter) 1 g.
Weighted mechanical actuation, gasketed 0.71 0.10 c 1.0
Weighted mechanical actuation, ungasketed 0.68 1.8 1.0

a The roof fitting loss factors, KFa, KFb, and m, may only be used for wind speeds from 2 to 15 miles per hour.

b Unit abbreviations are as follows: lb = pound; mi = miles; hr = hour; yr = year.

c If no specific information is available, this value can be assumed to represent the most common or typical roof fittings currently in use.

d A slotted guide-pole/sample well is an optional fitting and is not typically used.

e Roof drains that drain excess rainwater into the product are not used on pontoon floating roofs. They are, however, used on double-deck floating roofs and are typically left open.

f The most common roof leg diameter is 3 inches. The loss factors for 2 1/2-inch diameter roof legs are provided for use if this smaller size roof is used on a particular floating roof.

g Rim vents are used only with mechanical-shoe primary seals.