Caution over CO2 levels for HES testing

An IMCA, International Marine Contractors Association product story

Edited by the Engineeringtalk editorial team Jul 26, 2005

Following the completion of a specially commissioned study, IMCA is advising that caution should be exercised in relation to the CO2 level used in the testing of Hyperbaric Evacuation Systems.

In 1999, IMCA (International Marine Contractors Association) issued a protocol for the thermal testing of hyperbaric lifeboats, with an information note and technical information for those responsible for such testing.

The same protocol was then thoroughly reviewed and updated and in September 2004; 'The Evaluation and Testing of the Environmental Control of Hyperbaric Evacuation Systems (HES)' was published.

This protocol included an increased injection rate for carbon dioxide, based on figures for the metabolic heat output of divers.

"Despite detailed discussion prior to publication of the protocol, verification tests by members have identified that the stated figure may have been too high," explains IMCA's technical director, Jane Bugler.

"For this reason we commissioned Professor Michael Tipton of Portsmouth University, a leading expert on respiratory physiology, to undertake a series of representative tests and obtain data on CO2 production levels for subjects in an HES in different wave conditions with a view to recommending a reasonable and safe requirement for scrubbing CO2 within an HES.

"Professor Tipton's report has now been received and we will be updating the protocol to reflect the findings, and publishing a revised version of the protocol later in the year.

In the meantime we advise that caution should be exercised in relation to the CO2 level used in any testing undertaken".

Hugh Williams, IMCA's chief executive reflects what a long way IMCA has come in the past 10 years: "Calling on one of the UK's foremost experts on respiratory physiology is a measure of the levels to which we now work on behalf of our members in the quest for that holy grail - zero-injuries," he explains.

Copies of the HES protocol and further information on Professor Tipton's findings are available from IMCA.

About IMCA.

The International Marine Contractors Association is an international association with its 270+ members in more than 35 countries representing offshore, marine and underwater engineering companies.

IMCA has four technical divisions, covering marine/specialist vessel operations, offshore diving, hydrographic survey and remote systems and ROVs, plus geographic sections for the Americas Deepwater, Asia-Pacific, Europe and Africa and the Middle East and India regions, as well as a core focus on safety, the environment, competence and training.

IMCA seeks to promote its members' common interests, to resolve industry-wide issues and to provide an authoritative voice for its members.

IMCA publishes over 170 guidance documents and technical reports.

These have been developed over the years and are widely distributed.

They are a definition of what IMCA stands for, including widely recognised diving and ROV codes of practice, DP documentation, marine good practice guidance, the 'Common Marine Inspection Document', safety recommendations, outline training syllabi and the IMCA competence scheme guidance.

In addition to the range of printed guidance documents, IMCA also produces safety promotional materials and circulates information notes and safety flashes.