In June 2025, the IMO's Maritime Safety Committee adopted Resolution MSC.581(110), issuing Revised Recommendations for Entering Enclosed Spaces Aboard Ships — formally replacing A.1050(27). The objective is simple but urgent: reduce the persistent number of fatalities and serious incidents caused by unsafe atmospheres in enclosed spaces such as cargo holds, ballast tanks, pump rooms, and technical compartments.
What Has Changed Under MSC.581(110)?
The revised resolution introduces updated guidance on:
- Atmospheric testing requirements — more rigorous pre-entry testing protocols covering oxygen deficiency, flammable gases, and toxic vapour levels.
- Permit-to-work systems — clearer requirements for formal documentation, designated responsible officers, and defined approval chains before any entry commences.
- Standby and rescue provisions — enhanced requirements for trained standby personnel and rescue equipment to be in position before any entry begins.
- Competency requirements — updated guidance on the training and demonstrated competency expected of officers and crew members who supervise or participate in enclosed space entry operations.
- Drilling and familiarisation — increased emphasis on regular, realistic drills to ensure crew members can execute rescue operations effectively under pressure.
Critical fact: Enclosed space incidents remain one of the leading causes of multiple-fatality accidents in shipping. In many cases, rescuers are also overcome when attempting to recover the initial victim — a scenario that proper standby provisions and team training are specifically designed to prevent.
Implications for ISM Code Compliance
MSC.581(110) is a recommendation, not a mandatory regulation — but it will be incorporated into port state control inspection criteria and vetting checklists. Operators whose SMS procedures and crew training have not been updated to reflect the revised guidance risk adverse findings during PSC inspections and SIRE/CDI vettings.
How Singapore Marine Agency Supports Compliance
SGMA's audit and compliance team can assist operators in reviewing and updating enclosed space entry procedures within their SMS, assessing crew training records and competency evidence against MSC.581(110) guidance, facilitating drills and providing trained observers to evaluate crew performance, and preparing for HSEQ, ISM, and ISPS audits that incorporate the revised enclosed space requirements.
Contact us to discuss how we can help your fleet stay ahead of the latest MSC recommendations and maintain a strong compliance posture across your operations.