Use of handy boxes

[mtech]

Sorry if this is a duplicate, been searching for a while and haven't found the answer I am looking for. I currently have contractors installing 110v receptacles in an industrial facility. They are using handyboxes with KO's, I had always been told that you cannot surface mount handy boxes because the knockouts could be pushed in and shocked. Can someone point me in the right direction to the proper use and code section.

Thanks!

 

[renosteinke]

Since 'handy boxes' - the plain steel single gang boxes so beloved by handymen - lack any sort of mounting flange and do not accept mud rings .... where else can you mount them?

 

[jxofaltrds]

Didn't mean for the pic to be that big!

 

[fmtjfw]

Are the handy boxes being mounted on something or are they being suspended at the ends of cables.
Mounting, OK. Suspended, NoNo.

 

[jim dungar]

... I had always been told that you cannot surface mount handy boxes because the knockouts could be pushed in and shocked.

This is a design issue not covered by the NEC.

But along this line, do you surface mount a loadcenter that has knockouts in it?

 

[tom baker]

They are no different than a 4S box. the alternative would be an FS box. I wouldn't use a HB as they are too small.
But where OSHA does not allow HBs is on the end of a cord as HB is intended to be mounted on a wall.

 

[Strathead]

They are no different than a 4S box. the alternative would be an FS box. I wouldn't use a HB as they are too small.
But where OSHA does not allow HBs is on the end of a cord as HB is intended to be mounted on a wall.

While I hadn't thought of it before, the OP points out the potential difference. It seems to me you could theoretically push a KO pug in and contact the energized parts of a switch or duplex in a shallow hadny box. It seems far less likely in a 4S box since even a 2 gang the devices are further away. Electricians tape solves this dilemma though.

 

[jxofaltrds]

90.1 Purpose.
(A) Practical Safeguarding. The purpose of this Code is
the practical safeguarding of persons and property from
hazards arising from the use of electricity.

 

[GlennG]

I have never beeen able to figure out why someone would try to cram a device into a Handy box when you can use a 1900 instead. I actually came across a job where the homeowner had a single 220 receptacle jammed into a horizontally mounted handy box, with 10/3 romex going in one side and out the other!!! He must have used his foot to jamb the device in!

 

[kwired]

While I hadn't thought of it before, the OP points out the potential difference. It seems to me you could theoretically push a KO pug in and contact the energized parts of a switch or duplex in a shallow hadny box. It seems far less likely in a 4S box since even a 2 gang the devices are further away. Electricians tape solves this dilemma though.

If the KO is still attached to the box (just pushed but not broke free) that is supposed to be bonded to the equipment grounding conductor the overcurrent device should take over and open the circuit.

I have never beeen able to figure out why someone would try to cram a device into a Handy box when you can use a 1900 instead. I actually came across a job where the homeowner had a single 220 receptacle jammed into a horizontally mounted handy box, with 10/3 romex going in one side and out the other!!! He must have used his foot to jamb the device in!

I once seen a picture an inspector had from a HO installation - a handibox where they thought just because there are 8 KO's in the box you must be able to use all 8 at one time