I've had a safe in my farm shop for several years.  Had some sacks of grain in the shop and this led to grain moths.  They apparently seeked out my warm gunsafe and then the moths attracted spiders.   I'm going to have to totally empty it and give it a good shop vacking.  This is the first year that I've noticed a problem.  Cleaned out the grain but I'm thinking I need some sort of fumigant in my safe to prevent future insect intrusion.  What's safe, and what to use give me your suggestions.

I've read where moth balls paced in tool boxes prevent rust, but I'd be concerned about ingredients such as naphthalene, and how it may react with materials such as the finish on rifle stocks, plastics, and other coatings and treatments.

RAID