Thanks for your question. I will try to help.
If he is coming to the UK for simple training and will not actually be carrying out any formal work then he will have to apply for a standard visit visa,The webpage on this is here:
You will see that it confirms that if he visits for business then he is permitted to carry out training, which a health and safety course would fit in to.
Obviously, he (not you as employer) would have to make the actual application but you can execute a sponsorship declaration if you wish to asssit him.
You can go to a local solicitor to draft a sponsorship declaration in which you state the terms of his visit, that he is to return at the end of it and that you shall pay the costs of any unforeseen expenses that should occur during his stay so that nether of you will need to access public funds. This will help
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