The fastest way to test a fluorescent tube is with a multimeter set to continuity mode. If either filament is broken, the tube is dead. A multimeter allows you to perform basic electrical tests, providing crucial insights into the health of various components within your fluorescent fixture.
[pdf] North American distribution boards are generally housed in enclosures, with the positioned in two columns operable from the front. Some panelboards are provided with a door covering the breaker switch handles, but all are constructed with a dead front; that is to say the front of the enclosure (whether it has a door or not) prevents the operator of the circuit breakers from contacting live electrical parts within. carry the current from incoming line (hot) conductors to the breakers.
[pdf]