Marking Snap-Back Zones? Stop and Think!

If a mooring-line breaks under load, the sudden release of energy will cause the two broken ends of the line to recoil or ‘snap-back’ with high speed and force. Anyone standing in the snap-back zone is at risk of serious injury or event death.

North’s Loss Prevention team regularly conduct seminars for sea-staff employed on Members’ vessels. One of the most requested seminar topics is ‘Mooring Operations and Accidents’. Feedback from deck officers and ratings who have attended recent seminars is that ‘snap-back’ zones are still painted on the mooring decks on many ships as a matter of routine.

The painting on deck of mooring line snap-back zones became popular after the publication of the 2010 edition of the United Kingdom Marine and Coastguard Agency (UK MCA) ‘Code of Safe Working Practices for Merchant Seamen’(COSWP) which stated, under section 25.3.10:

“When moorings are under strain all personnel in the vicinity should remain in positions of safety, i.e. avoiding all ‘Snap-Back’ Zones. It is strongly recommended that a bird’s eye view of the mooring deck arrangement is produced (an aerial view from a high point of the ship can be utilised) to more readily identify danger areas”.

Many shipowners took this to mean that potential snap-back zones should be permanently painted on deck, which was not the MCA’s intention. The painting of snap-back zones on deck actually led to an increase in mooring accidents. The UK MCA therefore revised the wording in the 2015 edition of the COSWP, under section 26.3.2:

“Owing to the design of mooring decks, the entire area should be considered a potential snap-back zone. All crew working on a mooring deck should be made aware of this with clear visible signage”.

And under section 26.3.3:

“The painting of snap-back zones on mooring decks should be avoided because they may give a false sense of security”.

Potential snap-back zones should be discussed and identified during a toolbox talk before every mooring operation, but not permanently marked or painted. Also see our 2015 Industry News on the subject: Danger of Painting Snap-Back Zones on Deck