My garment is said to be chemical resistant, so what level of protection does it offer?

Firstly, if it doesn't meet EN465, EN466, EN467 or EN14605 then you are unlikely to be covered. Secondly, it depends very much on what tasks are being done. Some garments offer "full body" protection (EN465, EN466 or EN14605) and others offer just "part body" protection (EN467 and EN14605 [PB]). There is also a significent difference between "Type 3 (Liquid Tight) EN466 and EN14605" and "Type 4 (Spray Tight) EN465 and EN14605" garments.