CFR > Title 46 - Shipping > CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY > SUBCHAPTER F—MARINE ENGINEERING (parts 50 to 64) > PART 64—MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS > SUBPART B—Standards for an MPT (§64.11 to §64.55) > 64.19—External pressure.

64.19—External pressure.

(a) A tank without a vacuum breaker must be designed to withstand an external pressure of 7 1/2 psig or more.
(b) A tank with a vacuum breaker must be designed to withstand an external pressure of 3 psig or more.