46 CFR § 153.558 - Special requirements for phosphoric acid.
---
identifier: "/us/cfr/t46/s153.558"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 153.558 - Special requirements for phosphoric acid."
title_number: 46
title_name: "Shipping"
section_number: "153.558"
section_name: "Special requirements for phosphoric acid."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "O"
subchapter_name: "CERTAIN BULK DANGEROUS CARGOES"
part_number: "153"
part_name: "SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 3703; Department of Homeland Security Delegation No. 0170.1. Section 153.40 issued under 49 U.S.C. 5103. Sections 153.470 through 153.491, 153.1100 through 153.1132, and 153.1600 through 153.1608 also issued under 33 U.S.C. 1903 (b)."
regulatory_source: "CGD 73-96, 42 FR 49027, Sept. 26, 1977, unless otherwise noted."
cfr_part: "153"
---
# 153.558 Special requirements for phosphoric acid.
A phosphoric acid containment system must be:
(a) Lined with natural rubber or neoprene;
(b) Lined with a material approved for phosphoric acid tanks by the Commandant (CG-ENG); or
(c) Made of a stainless steel that resists corrosion by phosphoric acid.
“Phosphoric acid”, as defined in § 153.2, includes phosphoric acid, superphosphoric acid, and aqueous solutions of phosphoric acid.
[CGD 73-96, 42 FR 49027, Sept. 26, 1977, as amended by CGD 82-063b, 48 FR 4782, Feb. 3, 1983; CGD 88-100, 54 FR 40042, Sept. 29, 1989]