Breakers locked closed

[mtlogcabin]

They are required on fire alarm circuits per NFPA 72 and the 2020 NEC.

760.121(B) Branch Circuit.
The branch circuit supplying the fire alarm equipment(s) shall supply no other loads. The location of the branch-circuit overcurrent protective device shall be permanently identified at the fire alarm control unit. The circuit disconnecting means shall have red identification, shall be accessible only to qualified personnel, and shall be identified as “FIRE ALARM CIRCUIT.” The red identification shall not damage the overcurrent protective devices or obscure the manufacturer's markings. This branch circuit shall not be supplied through ground-fault circuit interrupters or arc-fault circuit interrupters. The fire alarm branch-circuit disconnecting means shall be permitted to be secured in the “on” position.

The last sentence was new to the 2020 code, but NFPA 72 says:

10.6.5.2.5
The circuit disconnecting means shall be accessible only to authorized personnel.
10.6.5.4 Circuit Breaker Lock.
Where a circuit breaker is the disconnecting means, an approved breaker locking device shall be installed.

 

[Inspector Gift]

They are required on fire alarm circuits per NFPA 72 and the 2020 NEC.


The last sentence was new to the 2020 code, but NFPA 72 says:

Jeff, Thanks for sharing the NFPA 72 citation. I have seen them only once in this jurisdiction, and approved based upon the purpose, but have long since forgotten where in the codes it was required.

 

[Inspector Gadget]

The answer is that you are absolutely allowed to lock it, and if the firefighters need to shut off the power, they have all manner of tools to get that lock off quickly at their disposal.

Reminds me of a file we had - building supply store. Canadian Codes often take into account how many sides a building fire can be attacked from. This place was largely gated, so I said one side.... this was early in my days looking at such things, so I called the local OFM for a second opinion.

"They got gate openers, kid. Painted red, weighs about six tons. You got a three-access building, not one."

 

[steveray]

Reminds me of a file we had - building supply store. Canadian Codes often take into account how many sides a building fire can be attacked from. This place was largely gated, so I said one side.... this was early in my days looking at such things, so I called the local OFM for a second opinion.

"They got gate openers, kid. Painted red, weighs about six tons. You got a three-access building, not one."

If my FD crashes their $1 million apparatus through a gate, they will have hell to pay....But they have K saws and a whole host of things to get through gates in rapid fashion, just like taking doors....Knox box comes to mind