Hi
I do a bit of health and safety in my current job what i would recommend is first visit the hse website, it is really good for getting/downloading information.
Your main goal as i see it would be firstly protect yourself for any injury you may perform on your customers.
Chemicals, use them correctly READ the datasheets.
Suppliers must give you these by LAW.
Make sure you use the CORRECT Personal protective equipment
PPE.and maintain it.
Make sure you pat test your equipment incase you fry a customer.(Get yourself some stickers and a multimeter keep a log of checks.)Earth continuity.
Make sure you label all decanted fluids correctly.
Dont take any risks with chemicals.
you probably wont need a policy and if you decide you do then just copy one from the web and edit it. to get yourself a start point.
http://www.hse.gov.uk/pubns/indg259.pdf will be good for you.
Don't be scared by it all , remember if you get a member of staff who does not act safely and you catch them warn them in writing, if they misbehave again SACK EM
sounds harsh but it can be you future they are messing as well as thier own health,
One definatley to watch out for is minors , dont employ them without making sure they can't get hurt and have a mentor , employing a youngun in the summer holidays has cost a lot of small businesses more than it was worth.
http://www.hse.gov.uk/pubns/indg324.pdfhttp://www.hse.gov.uk/pubns/indg259.pdfBest of luck
Alex