Hi Miriam,
I’m glad to hear you are taking resin safety seriously. It’s something that’s important to me as well!
Your best resource for using resin safely is the product’s safety data sheet (SDS). That document details how to use the resin carefully, including all safety precautions you need to take. BUT, You are never wrong to be even safer. For example, if a resin kit’s SDS does not specify wearing a respirator, but you feel safer wearing one, then do it.
On another note, I would never use a resin that didn’t conform to ASTM D-4236 or didn’t provide a safety data sheet. They are many resins on the market that don’t do either. You can feel comfortable that all the resins sold in the Resin Obsession store do both. https://shop.resinobsession.com/collections/resin
If you want to get even deeper with resin safety recommendations, I’ve got more articles here: https://resinobsession.com/tag/safety/