Late onset of decompression illness (DCI)

  • Safety Flash
  • Published on 1 May 2004
  • Generated on 7 December 2025
  • IMCA SF 04/04
  • 2 minute read

IMCA has received a safety notice which provides a good reminder on the subject of decompression illness (DCI).

What happened?

A company has reported that, following an air dive, a diver developed a pain in his arm more than seven hours after decompression. Due to the length of time between the dive and the complaint appearing, it was assumed not to be diving related and painkiller medicine was administered. On worsening, two hours later, the diver was recompressed, but his condition did not markedly improve. It is believed that the period of non-recompression allowed the gas bubble(s) in his tissues to expand and cause internal lesions before dissipating. Thus the later therapeutic treatments, designed to dissolve the offending ‘bubbles’, were unsuccessful, as they could not provide relief for existing physical lesions.

The company has reminded its personnel that whenever a diver reports complaints which appear consistent with type I and/or type II symptoms, even up to 48 hours following an air or nitrox dive, the divers must be recompressed immediately, in accordance with company DCI treatment procedures. This should take place immediately – before or in parallel with contacting the diving doctor. If the case is DCI, correct action will have been taken. If it is not a DCI, therapeutic recompression will not make things worse.

Latest Safety Flashes:

Vessel ran aground

A vessel on a short voyage ran aground while navigating through a narrow channel at low tide.

Read more
Fire in the engine room – fuel spray fire

A fire broke out on the starboard main engine due to a leak from the fuel pipe connection.

Read more
Fire hazard: missing splash tapes on fuel hose connections

It was observed that several engine fuel hose connections were not fitted with splash tapes.

Read more
Dropped pallet during cargo transfer

A plastic pallet loaded with plastic lube oil drums fell while being hoisted.

Read more
Positive – Enhancing safety communication through digital monitors

All crew and office personnel have 24/7 access to essential safety and operational updates.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.