In Class III locations, which types of fittings can be used for bonding purposes?

In Class III locations, which are typically considered to be areas where ignitable fibers or flyings are present and are classified as hazardous, it is essential to use fittings that ensure effective bonding to prevent static electricity buildup and potential ignition sources. The correct answer indicates that both locknut-bushing and double-locknut types of fittings can be utilized for this purpose.

Locknut-bushing and double-locknut fittings are designed to provide secure connections that can mitigate the risk of electrical arcing and enhance the grounding and bonding of electrical systems in environments prone to hazardous conditions. These fittings allow for a reliable and conductive path that connects equipment to ground, which is critical in preventing electrical incidents in Class III locations.

Other options mentioned do not meet the necessary criteria for effective bonding. For example, single-locknut fittings may not provide the same level of security as double-locknut fittings, and using only insulated fittings would not facilitate proper bonding, as insulation can interrupt the necessary conductive path required for grounding. Thus, the use of locknut-bushing and double-locknut fittings represents the best practice for ensuring safety and compliance in hazardous environments.