IACS interpretations on SOLAS safety standards

Eda Zenic -

The International Association of Classification Societies (IACS) has issued several Unified Interpretations (UIs) to clarify and standardize the application of specific safety-related provisions in the International Convention for the Safety of Life at Sea (SOLAS). These interpretations address electrical safety, escape routes, collision bulkhead valves, and safety systems in cargo pump-rooms. Below is a detailed summary of these interpretations and their implementation timelines.

Precautions Against Electrical Hazards in High-Risk Areas (SC11)

IACS has provided guidance on implementing SOLAS regulation II-1/45.5.3, which aims to mitigate risks from electrical hazards. Essential cables and wiring for emergency systems, including power, lighting, communications, and signaling, must be routed away from high fire-risk areas wherever practicable. These high-risk areas include cargo spaces carrying flammable goods, vehicle and ro-ro spaces, spaces storing flammable liquids, and pantries with cooking appliances.

By avoiding these areas, the integrity of critical electrical systems is preserved during emergencies. This interpretation is being implemented in two phases:

  • Ships contracted for construction on or after July 1, 2022, must comply with Rev.1.
  • Rev.2 updates are effective for ships contracted on or after January 1, 2026.

Escape Routes from Steering Gear Spaces (SC269)

To enhance crew safety, IACS clarified the expected escape route configurations for steering gear spaces under SOLAS II-2/13.4.2.2 and II-2/13.4.2.3.

  • Spaces without emergency steering positions: Only one escape route is sufficient.
  • Spaces with emergency steering positions:
    • Should have two escape routes unless there is direct access to the open deck.
    • If two escape routes are necessary, they are not required to lead directly to the open deck.

These provisions aim to ensure safe evacuation from steering gear spaces during emergencies. The interpretation applies to ships regardless of size and is phased as follows:

  • The original interpretation applies to ships contracted on or after July 1, 2016.
  • Rev.1 updates apply to ships contracted on or after January 1, 2018.
  • Rev.2 applies to ships contracted on or after January 1, 2026.

Guidance on Valves Piercing the Collision Bulkhead (SC306)

This interpretation provides guidance on compliance with SOLAS II-1/12.6.2, which permits a collision bulkhead to be pierced by one pipe for servicing the forepeak tank. The pipe must be fitted with a remotely controlled valve located at the bulkhead. The interpretation specifies that the valve:

  1. Can be either a manually operated or mechanically powered type with a fail-close arrangement.
  2. Must be capable of being closed manually or automatically if the remote control system fails.
  3. Must be made of steel, bronze, or other approved ductile material (ordinary cast iron is not acceptable).

These guidelines provide clarity on the acceptable materials, designs, and fail-close mechanisms for such valves. The interpretation applies to ships contracted on or after January 1, 2026.

Gas Detection and Bilge Alarms in Cargo Pump-Rooms (SC307)

IACS has clarified the use of hydrocarbon gas detection and bilge alarm systems in cargo pump-rooms, under SOLAS II-2/4.5.10. These systems are essential for detecting hazardous conditions and ensuring timely alerts.

Gas detection systems:

  1. Should continuously monitor hydrocarbon gas concentrations.
  2. Alarms (both visual and audible) should activate in the pump-room, control rooms, and navigation bridge when concentrations reach 10% of the lower flammable limit.
  3. Detectors must be strategically placed, covering key areas such as near pumps, 30 cm above the floor, near the ceiling, and in areas with limited airflow.

Bilge alarms:

  1. High liquid levels in the bilge should trigger alarms in the pump-room, cargo control room, engine control room, and navigation bridge.

These measures aim to ensure early detection of gas leaks and flooding risks, enhancing safety in pump-rooms. The interpretation applies to ships contracted on or after January 1, 2026.