The present disclosure relates to methods and devices for controlling arthropods, including insects and arachnids in an environment. The methods generally comprise: generating a near-ideal gas Purified Hydrogen Peroxide Gas (PHPG) that is substantially non-hydrated (e.g., in the form of water in solution or water in solution or water molecules bonded by covalence, van der Waals forces, or London forces) and substantially free of, e.g., ozone, plasma species, and/or organic species； and directing the gas comprising primarily PHPG into the environment such that the PHPG acts to control arachnids in the environment. In certain aspects, the arachnids may be totally or partially killed.
