Do you mean steps as in door steps, stairs or stepladders?

There are two sets of regulations that may be relevant. The Workplace (Health, Safety and Welfare) Regulations speak in broad generalities and don't have the kind of quantitative standards you're looking for. The Building Regulations do go into the dimensions that this kind of feature should be built to, but they are not a legal standard for existing features, only for how new ones should be built (and generally, over time, they have become more and more demanding). What is the problem you are trying to solve? Identifying legal standards often isn't the best approach.

Wow! Brilliant example of life-long-learning. I had no-idea that the Building Regs do no not apply to existing structures. I have spent Capital in the past ripping up some ridiculous 'slab' style steps insisting the rise and going did not meet the Building Regs. I must add no-one challenged the decision as the steps really were beyond a joke. There you go- I'm not perfect - just 99% perfect ;-) (and still don't actually believe it until I see it with my own eyes- off to do some googling now!)

Are you based in UK? If not ( as you appear to be a member of the Carribean Branch) the regulations quoted do not apply. You could refer to them as good practice and a standard to meet.