Firstly, always ask your insurnace company regarding ANY change of your working situation. If you don't say anything and are unfortunate and have an accident you could find yourself in serious HOT WATER!!!
Ok, if the company has asked you to use this equipment you need the following:
1) Copy of their insurance regarding the equipment and that a Sub Contractor can use it.
2) A copy of the test certificate to ensure it is in good working order.
3) Health and Safety requirements
4) Risk assesment
If they cannot provide this information then contact your insurance company. Give them the date and times you will be using the machinery and ask for them to cover you for this particular job, it will be considerably less than £10,000 !
Yes, some people may think this is a lot of hassle, however, remember, if you are up in the air and things go wrong you need to ensure you cave complied with everything.
I worked on a site last year, a sub contract builder borrowed a cherry picker that a painter had hired on site. He lost control, the boom arm swung round and he hit the corner of a Glass Apex and caused £1000's upon £1000's worth of damage. The main building company sued him and his insurance didn't cover him to use such equipment, he went bankrupt over the cost involved!! I know this because I work closely with the main building contractor and they now have very strict policies we all have to adhere to!
Just be warned !
Regards, Trev