Posted By John Allen Owen, I don’t think your installation will count as an Offshore Installation under the Offshore Regulations, the reason being that it is not handling hydrocarbons or extracting minerals by means of a bore hole. Precautions need to be taken however and your risk assessment for access to the platform will need to look at issues like, safety of the means of access, wind, tide and wave conditions and means of rescuing a person who falls in the water. What will happen for instance if people are landed on the installation and then cannot get off again due to a change in the weather? Is there a shelter with emergency food and water supplies? You should look for general guidance on civil engineering projects on or over water.

Posted By Chris Packham Owen I would add to the shelter, etc., a two-way radio to allow communications. True the individual workers may have their own with them but this may only have limited battery life and communication can be important in organising rescue, dealing with any (medical?)emergency and for morale. Chris

Posted By Dave Merchant Your situation is similar to wind farm access, in that it's "off shore" in a practical sense, but not "offshore" in a legal one. The BWEA has extensive safety guidance notes for offshore access which you might find useful, covering things like what emergency provisions should be carried, etc. http://www.bwea.com/safety/ In terms of training, typically people accessing an inshore platform from a boat are expected to either have basic offshore survival or be accompanied by two people who have (so any one casualty can be lost o/b and there's still a trained person to handle it). Immersion suits are generally not required for inshore waters when the water temp is over 20C and there's a standby vessel, but of course lifejackets are essential. Depending on how the platform is accessed, they may need harnesses and WAH/rescue training too. It's possible (but not guaranteed) that you'll have a cell signal out there, given the distance from shore - but you can't rely on it. The boat will have comms, so can always be used to relay messages.

Posted By John Allen Dave, thanks for the link to the BWEA. I've just started working on a project to build a barge which may be used in offshore windfarm construction. The link to the trade association site is very useful.