if you employ someone you have to have a health and safety policy and if your company employs five people or more this policy has to be a written health and safety policy.
it is your duty to ensure your staff are trained for the work they are doing and you should do a risk assesment for all work undertaken.
training should cover safe,storage use and handling of chemicals used .(coshh) and lots more including manuel handling,working at height etc
if you google hse (health and safety executive) the website gives all the information you need under health and safety guidance.
it sounds more complicated than it actually is .
see previous post re health and safety training
the above information is given to steer you in the right direction, i am not qualified to give health and safety advice as i am only studying for my qualifications which i have not yet got.