Hi Lorraine

That's one of those "how long is a piece of string?" questions!

Depends on your background, how much you enjoy your current job and where you think you might want to go.

But possibly about seeing H&S as a benefit, assuming it is done proportionately, rather than being focused on "compliance". 

If the focus is on "compliance" you could soon find yourself in a tick box.

If you are looking at the benefits you might find yourself counting ticks and other sources of biohazards. You might broaden from H&S into e.g. adding on environment or many other areas. So from ticks, perhaps you might move on to phytophthoras.

After a Level 3 OSH qualification, one logical next step would be to move sideways into a similar qualification in an associated discipline such as environment, quality, fire, etc, or upwards via a Level 6 qualification. 

But probably wise to keep your options open and see how you feel when you get that Level 3 first.