Article 358 covers the use, installation, and construction specifications for EMT and associated fittings. As noted in Sec. 358.42, "Couplings and connectors used with EMT shall be made up tight.

I’m not sure what caused this EMT coupling to snap apart, but it resulted in damaged circuit wires and a compromised equipment ground path. This installation no longer complies with Sec. 300.10 with ...