have you considered doing the nebosh course yourself ? , it is usually done over twelve days ,(1 day a week ) but courses are also done intensively over two weeks or in the evenings,costs can vary, there are three colleges in my area charging £350 , £600 , and £850 (big difference in costs eh). it is quite a high level qualification though.
i am doing the course at the moment , i will be taking my exams in june (two written exams),i pased my practical last year.