IACS has revised the safety measures against chemical treatment fluids

The International Association of Classification Societies (IACS) has released a Unified Requirements document relating to the safety measures against chemical treatment fluids used for exhaust gas cleaning systems and the residues which have hazardous properties.

This document (UR M81 REV1 CLN) has been released on 1 July 2023 and will enter into force on 1 July 2024.

Under MARPOL Annex VI's regulation 14, ships must use fuel oil with limited sulphur content as per regulations 14.1 or 14.4.

Regulation 4 permits an alternate compliance method, endorsed by the Administration, that matches emission reduction effectiveness of Annex VI's requirements, including regulation 14 standards.

Certain exhaust gas cleaning systems, approved by the Administration as "alternate compliance methods," involve chemical use stored in bulk.

This UR's specified safety guidelines for chemical treatment fluids are applicable to these systems.

"Chemical treatment fluid" in this context denotes corrosive sodium hydroxide (NaOH) or hazardous calcium hydroxide (Ca(OH)2) solutions (Refer to section 2).

For exhaust gas cleaning systems employing different chemicals, safety protocols are determined through a risk assessment.

This assessment mitigates personnel hazards linked to these systems, aiming to reach a level equivalent to M81 2.1 to M81 2.16 compliant systems.

This UR requires consistent adoption by IACS Societies for EGCS under two conditions:

• i) for applications submitted on or after July 1, 2022, or
• ii) for installations in ships contracted for construction on or after July 1, 2022.

Rev.1 of this UR mandates uniform adoption by IACS Societies for EGCS under similar circumstances but for the dates of July 1, 2024.

The term "contracted for construction" signifies the date when the shipbuilding agreement is signed between the potential owner and the shipbuilder.

Refer to IACS Procedural Requirement (PR) No. 29 for more information on the "contract for construction" date.

For more information, please see the document below (available only to subscribers):

Safety Measures Against Chemical Treatment Fluids Used for Exhaust Gas Cleaning Systems and the Residues Which Have Hazardous Properties