As a HSE officer for a sub-contracting company, I have visited a site that has major non compliances and is dangerous. They have ignored the recommendations of my reports and the site is now getting worse.

Should I report the main contractor to HSE, even if it means I might lose my job for damamging my employer commercially?

How likely it is that you will get another job, continue to report and raise matters on site, remember they are grown men/women if they take no notice then isn't thier responsibility.

Explain to other workers who might be acting in a safe manner what the consequences could be for them.

I could live with myself if some halfwit decided to go against what I told and got hurt or killed, not sure what life my family would have without me earning.

Why not position yourself somewhere in the middle................
email something like,
Dear X, as part of my role I visited the site again recently to note that none of my recommendations have been implemented and standards remain poor. Accordingly I see little point in future visits that will do little more than generate duplicate reports of my previous visits, that are not acted upon. I consider that I have fulfilled my role in bringing this to your attention, and that the current site standards, deterioration, or improvement, now rest with yourself.

let me ask this question...are all the non conformance's you have identified high risk/medium risk/ low risk?...why not use the cost of each based on the risk and present it in that way....or the risk of losing the contract....or suggest a few solutions...ist a bit like crtisisng someones driving...everyone is perfect in thier own eyes...

Correct me if i'm wrong the title of the post is 'whistle blowing' I was under the impression that whistle blowing is protected by Law and you cannot loose your job over it.

It is in the interest in protecting others? If it is then your job may be protected.

Very difficult position given the poor track record of people using PIDA especially if you want to keep your job.
Same thing for lots of people using employment protection laws=complain/take action or keep your head down and hang onto your job-hopeless
You could always use Public Concern At Work-a whistle blowing charity which may help/or advise you and which provides a safer means of getting the message over without putting your head over the parapet-easy contact on the net.
Pretty well all commentators inc MP's find that whistleblowers are poorly protected-and you wouldn't want to try it in the NHS-see Private Eye ad nauseum
Or you could send me details and I'll do it for you if possible. I'm retired and live in la belle France so they'll find it difficult to do owt here
Regards
Mike
PS And people are always saying that we should learn the language and use the culture of management to get our advice over effectively, yeah right. What sort of leadership is that then?

Whats the problem just ring up or email or send a letter with all the non-conformities to the HSE, Fire brigde or environment agency anonymously and they will come in an sort the employer/site out nobody will know who whistle blew, it could be a member of the public, contrator or uion rep who sent it, after all thats what the HSE poster has the local hse office number on for, Ive done this a few times and it always get the situation resolved, strange how somebody outside the organisation out of the contol of the paymasters gets things done AKA the Authorities.