Garage Receptacles

[Aaron Miller]

Can someone remind me what the NEC reference is prohibiting receptacles within 18" of residential garage floors?

Thanks,

Aaron:confused:

[Jerry Peck]

Aaron,

There is no NEC prohibition against having a receptacle that low ... BUT ... they are "ignition sources". ;)

[Aaron Miller]

Could they then fall under IRC 1307.3?

thanks,

Aaron

[Jerry Peck]

Could they then fall under IRC 1307.3?

thanks,

Aaron

That and every section which references elevation of ignition sources.

Basically as the receptacle itself, unused, is not a hazard, however, as soon as something is plugged into it (which would be an appliance of some type), then it now becomes a potential hazard as it now can become an ignition source. Being as the only reason to provide a receptacle outlet is to allow being able to plug something into it, yes, then the receptacle by itself does present a problem.


IGNITION SOURCE. A flame, spark or hot surface capable of igniting flammable vapors or fumes. Such sources include appliance burners, burner ignitions and electrical switching devices.

I.e., if it were never to be used, no problem, however, because 'it is there', the risk of it ever being used is there also, thus, either remove it (so it never can be a problem) or relocate it to a height which places it above the recognized 'safe' height of 18 inches.

[Jim Luttrall]

Could they then fall under IRC 1307.3?


Just my opinion, but that would be a stretch since it specifically requires "appliances" having an ignition source to be elevated.
If you go with this reasoning, then you would also have to install protection from impact for all outlets in a garage or carport because you are calling an outlet an appliance in order to make it fit that code.

[Jerry Peck]

Just my opinion, but that would be a stretch since is specifically requires "appliances" having an ignition source to be elevated.

Jim,

Read the definition of "ignition source".


If you go with this reasoning, then you would also have to install protection from impact for all outlets in a garage or carport.

I'm not, and I suspect that neither is Aaron, implying that the receptacle outlet 'requires protection from vehicle damage", only that "ignition sources" (and it is one) need to be elevated above 18 inches above the garage floor.

[Jim Luttrall]

I'm not, and I suspect that neither is Aaron, implying that the receptacle outlet 'requires protection from vehicle damage", only that "ignition sources" (and it is one) need to be elevated above 18 inches above the garage floor.

Glad of that, but the elevation of all ignition sources is not the intent of the Appliance Installation section M1307. It is dealing with Appliances.

Agreed?

[Aaron Miller]

ECJ:

Thanks,

Aaron:D

[Jerry Peck]

Glad of that, but the elevation of all ignition sources is not the intent of the Appliance Installation section M1307. It is dealing with Appliances.

Agreed?

Yes and no.

It is dealing with ALL "ignition sources" 'built into the home', it cannot, or course, address someone with an "ignition source" on the end of an electrical cord modifying something else ... i.e., someone using a drill or saw to cut or drill something, nor does it attempt to address anyone picking up a propane or MAP gas torch and using it at floor level.

That said, every "appliance" has, in some way, a connection to 'the built in energy source of the house', in this case, the electrical outlet, and that electrical outlet ... allow me to give an example:

Water heater, gas or electric, with a hot water re-circulating system where the pump is plugged into a receptacle outlet 6" above the floor.

The cord and plug is part of "the appliance" which is "the motor and pump", which is part of the re-circulating system for the hot water.

The receptacle outlet of and by itself had nothing to cause an arc (okay, if the wires come loose or break, the hot and neutral or ground could come in contact with each other, thereby creating the arc / spark which would indeed by an "ignition source"), however, as soon as a cord and plug is plugged into the receptacle outlet and current flows, there is the potential for arcing and sparking (we've all seen our share of burned up plugs and receptacles, haven't we).

Thus, that now becomes an ignition source which is less than 18 inches about the garage floor.

Thus, yes ... related to any and all "appliances" ...

From the 2006 IRC.
- APPLIANCE. A device or apparatus that is manufactured and designed to utilize energy and for which this code provides specific requirements.

... *ALL* "appliances".

And, thus, no ... not related to so idiot using a propane torch and igniting the gas fumes fulling the garage while he is laying the garage floor under his car.

[Aaron Miller]

It is dealing with ALL "ignition sources" 'built into the home'


Agreed.

Aaron

[John Steinke]

The reference you seek applies only to commercial garages and repair facilities (think: old fashioned gas station), and is not a prohibition, as much as a defining of the area within 18" of the floor as a 'classified' location, thus requiring special wiring methods.

This stricture does not apply to a place where you simply park your car.

The plumbing codes have a similar stricture that does apply, but only to open flames.

[Aaron Miller]

John:

I think Jerry's point is that, for the client's well being, it behooves the inspector to interpret the existing residential codes erring (perhaps) on the side of safety.

Aaron

[Jerry Peck]

This stricture does not apply to a place where you simply park your car.

The plumbing codes have a similar stricture that does apply, but only to open flames.

It does, and that is why "ignition source" has been defined.

For many years 'electrical arcing, switching, etc.' had been left up to the AHJ, some thought it through and said 'Yes, those things *are* "ignition sources".' while other AHJ said 'No, that only applies to "open flames".'

The definition of "ignition source" now includes ... SPECIFICALLY INCLUDES ...

(bold and underlining are mine)

IGNITION SOURCE. A flame, spark or hot surface capable of igniting flammable vapors or fumes. Such sources include appliance burners, burner ignitions and electrical switching devices.


Not a figment of my imagination, John, it's there, and spelled out, and, best of all, that definition states "Such sources include", and does not say 'Such sources are limited to'. That definition is giving you ideas and suggestions as to what is considered an ignition source, but is not limiting you from including other ignition sources which are not specifically stated.


This is from the 2003 IRC Commentary. (bold and underlining are mine)


- IGNITION SOURCE. A flame, spark or hot surface capable of igniting flammable vapors or fumes. Such sources include appliance burners, burner ignitions and electrical switching devices.


- - Any energized portion of an electrical system that can generate a spark or that can produce significant heat (often referred to as "glow", as in a heating element) is an ignition source should it come in contact with flammable gasses or liquids. Understandably, any open flame (such as a pilot light) is also an ignition source.




It then goes on to state the obvious: "Understandably, any open flame (such as a pilot light) is also an ignition source."

[Aaron Miller]

It seems to me that this is quite similar to the requirements set forth in NFPA 58 for the placement of propane storage tanks. A/C window and condenser units are considered to be sources of igntion, as are any sources of ignition. This is defined as:

3.3.67 Devices or equipment that, because of their modes or use of operation, are capable of providing sufficient thermal energy to ignite flamable-LF-gas-vapor-air mixtures when introduced in such a mixture or such a mixture comes into contact with them, and that will permit propagation of flame away from them.

Aaron

[Richard Abrams]

In our AHJ it is not allowed because of the "ignition sources" view. It is more likely to have gas and fumes down low so all ignition sources are kept to over 18 inches. And especially if there is a natural gas appliance in this garage.