(Confined) Enclosed Space Entry and Rescue 25.05.2024 12:39Entry into (Confined) Enclosed Spaces onboard ships is sometimes a necessary but dangerous work activity.
An Enclosed Space is a space with poor or no natural ventilation which is not designed for continuous occupancy, where access is limited and which may contain a dangerous atmosphere.
Enclosed spaces include but are not limited to cargo tanks, double bottoms, cargo pumprooms, duct keels,1 ballast tanks, void spaces, peak tanks, cofferdams, chain lockers, bunker tanks, freshwater tanks, machinery internals and any other spaces that are normally kept closed.
An enclosed space may include a deck area that due to its construction and location has poor or limited access and where a dangerous atmosphere may accumulate. The hazards identified below may be present around such a deck area.
Due to the high risks associated with enclosed space entry and the number of accidents that have occurred on board various types of ship, IMO has issued two specific sets of safety Guidelines:
1. Assembly Resolution A.1050(27) (Revised Recommendations for Entering Enclosed Spaces Aboard Ships);
2. MSC.1/Circ.1401 (Guidelines on Tank Entry for Tankers Using Nitrogen as an Inerting Medium).
The above IMO Assembly Resolution and Guidelines are important documents that should be followed when entering enclosed spaces and when inert gas (nitrogen) is used as an inerting medium. The guidance provides for practical application of these IMO guidelines.
Enclosed space atmospheres can be hazardous due to one or a combination of the following conditions:
- Oxygen deficiency;
- Inert gas including nitrogen;
- Presence of toxic and/or flammable gases;
- Accumulation of toxic and or heavy gases at lower levels within the space; and/or
- Oxygen enrichment.
