The coastguard operates four S-92s based on Shetland and Lewis
Urgent checks have been ordered on the gearboxes of helicopters operating in the North Sea.
Manufacturer Sikorsky is telling helicopter companies worldwide to carry out inspections after cracks were found in the gearboxes of S-92 helicopters.
Bristow and CHC, which operate the aircraft for rescues and transporting offshore workers to oil platforms, said it would comply fully with the request.
The gearboxes will now be checked after every 10 hours of flying.
A CHC spokesperson said: "CHC has had no recent issues with the S-92 that it operates in the UK North Sea and currently complies with the latest maintenance guidelines, which involve regular inspections, undertaken after every 10 flying hours.
"This equally applies to the four S-92 search and rescue aircraft it operates on behalf of the Maritime and Coastguard Agency.
"We will continue to take advice from the manufacturer and welcome any proactive measures to further enhance the safety and reliability of the aircraft."
A spokesman for Bristow said: "Bristow Helicopters is complying fully with the enhanced inspection regime required by Sikorsky during the manufacturer's investigation of cracks reported in some S-92 gearbox feet.
"Safety is always our first priority and inspection of the feet is required every 10 flying hours, which means daily inspection for Bristow's Scatsta fleet of S-92s."
The Unite union expressed concern, and said it would be seeking reassurances from Sikorsky, as well as raising it with the Health and Safety Executive (HSE) and the helicopter liaison group on behalf of the offshore workforce.
The helicopters were given the all-clear in March after being grounded following a fatal crash in Canada.