There are health and safety officer jobs both onshore and offshore. Energy Insider YouTube channel have started publishing videos and one of their first is about HSE jobs or health and safety jobs in the energy industry.
Check out their video.
In the video, the guys visit a recruitment company called AAA to ask about the safety jobs in the energy sector. With some cool and professional cinematography, that makes the subject a bit more fun. See the health and safety job video here
They got some groupings for salaries, how much you were paid oviously depends on the level; HSE advisor, auditor/co-ordinator, manager or director.
NEBOSH and IOSH were the 2 courses that were mentioned in the video. Also auditor courses were mentioned as you progress in your career. The offshore survival courses are a must if your are working offshore, the BOSIET for oil and gas, and GWO BST for wind turbines.
Energy Insider also interview an HSE manager for a wind turbine service company called Aratellus. And they get info from him about being an HSE officer offshore, and also how to get a job as one.