46 C.F.R. § 154.445 Design vapor pressure.
Title 46 - Shipping
If the surfaces of an independent tank type B are mostly flat surfaces, the Po must not exceed 69 kPa gauge (10 psig).
Title 46: Shipping
PART 154—SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES
Subpart C—Design, Construction and Equipment
Independent Tank Type B
§ 154.445 Design vapor pressure.