There really is no right answer to this question. The merits of safety training are highly subjective. There are three perspectives to look at when considering the depth of safety training to provide:
1. Legal requirements
2. Industry requirements
3. Your moral conscience
Legal requirements are horribly vague on overall safety training. OH&S legislation in each province and to an extent in each State relies heavily on "principles" and "due diligence". You develop your safety programs (including training) according to the principles, then if anything goes wrong, you must prove you were diligent in satisfying the requirements, based on what your industry peers would be reasonably expected to do.
So that leads us to the next consideration; industry requirements. Certain industries, such as oil and gas, or construction, have industry associations which provide guidance in the form of "Industry Recommended Practices" or IRP's. Enform is one of the most thorough at fulfilling this role. On safety training specifically, they had written IRP16(now withdrawn), which they call Basic Safety Awareness Training. At SafetySync, we liked this document so much, we essentially used their Appendix C as a roadmap for developing our inventory of safety training courses. The problem with this strategy is that we've now accumulated over 200 lessons, which total 50 hours of training. New lessons are constantly being added and existing ones updated. (Not easy to manage)
50 hours of safety training does seem at first like an awful lot. Especially with Enform's own Petroleum Safety Training (or PST 2.0) running at about 4 hours or the eGSO which runs about 30 minutes. The eGSO has been presented as the "minimum standards for a general safety orientation." I don't know of any job site that would allow their workers to only have eGSO training so I suspect that no one really considers it the minimum.
So does this mean that you can really send your workers on site with just their eGSO or PST?
It depends if your moral conscience will allow it. There are many more hazards in your line of work besides those touched-on in PST or eGSO. And there is considerably more knowledge pertaining to those hazards that might help your workers remain safe. Up until the last few years, there was no cost effective way of providing that information to employees. Some large companies, like Precision Drilling and Trican incur tremendous expense to bring all their employees to a centralized location for 5 days (40 hours!) of safety orientation and training. In most cases though, employers and safety professionals counted on supervisors to fill in the blanks. But if you choose the latter route, can you prove the training took place? And can you be sure your workers have been given the safety knowledge they need, especially with today's mobile workforce?
Fortunately, with the advent of online safety training, this extensive knowledge is readily available, and can be disseminated to anyone, at any time. Some providers, like SafetySync, allow safety managers to pick and choose which lessons to provide each job role within their company. In other words, you can leave out the lessons on Asbestos and Silica Dust if your workers never encounter those hazards. With the right tweaking, you can probably pare 50 hours of training down to about 15. You can even make the additional courses optional for your workers which is really going above and beyond. Iif your workers have access to the internet at the job site, they can take their training during slow periods while they wait for cement to harden or paint to dry.
So, to answer the question... You should provide your employees with safety training on any topic that is relevant to their work. This approach will satisfy legal, industry and your own moral obligations. Fortunately, with advanced online training systems, you can now do this easily, and without breaking the bank!