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Circular: Length of diving umbilicals for manned underwater operations

In a circular to the industry, the PSA clarifies matters relating to the length of diving umbilicals for manned underwater operations.


Over the last two years, the Petroleum Safety Authority Norway (PSA) has noted that operating companies and diving contractors have increasingly used diving umbilicals that are significantly longer than the 45 metres which the NORSOK standard says should not be exceeded.

Extended umbilicals for divers have been used as a risk-compensation measure for the overall operation and for the diving support vessel itself, so as to allow the vessel to standoff farther from the facility.

The PSA is of the opinion that this may lead to divers being exposed to unacceptable risk, and that the practice contravenes the regulations.

In the letter, circulated on 19 January 2015, we refer to the following regulations and guidelines:

Activities Regulations Section 93 Manned underwater operations

When conducting manned underwater operations, operational measures shall be implemented to prevent those participating from being subjected to injury or illness, and to reduce the likelihood of mistakes that can lead to hazard and accident situations. Cf. ChapterVII.

Framework Regulations Section 11 Risk reduction principles

Harm or danger of harm to people, the environment or material assets shall be prevented or limited in accordance with the health, safety and environment legislation, including internal requirements and acceptance criteria that are of significance for complying with requirements in this legislation. In addition, the risk shall be further reduced to the extent possible.

In reducing the risk, the responsible party shall choose the technical, operational or organisational solutions that, according to an individual and overall evaluation of the potential harm and present and future use, offer the best results, provided the costs are not significantly disproportionate to the risk reduction achieved.

If there is insufficient knowledge concerning the effects that the use of technical, operational or organisational solutions can have on health, safety or the environment, solutions that will reduce this uncertainty, shall be chosen.

Factors that could cause harm or disadvantage to people, the environment or material assets in the petroleum activities, shall be replaced by factors that, in an overall assessment, have less potential for harm or disadvantage.

Assessments as mentioned in this section shall be carried out during all phases of the petroleum activities.

This provision does not apply to the onshore facilities' management of the external environment.

We also point to:

NORSOK U-100 concerning manned underwater operations

The standard describes factors relating to the length of diving umbilicals.

In the letter, the PSA reminds recipients of its circular concerning the unacceptable use of risk calculations for deviating from the requirements of HSE legislation, and especially item 3 concerning the unacceptable use of risk calculations as an argument for choosing solutions which provide a lower level of safety than the established minimum level.

The PSA believes that the industry's use of very long umbilicals for divers, as a compensatory measure for a lack of space for diving support vessels and/or difficulty of access to the divers' worksites, will normally be in contravention of the regulations.

 

Contact: Bjarne Sandvik, phone +47 51 87 34 50, e-mail: Bjarne.Sandvik@ptil.no