Help Interpreting NEC 240.24(B) - Each occupant shall have ready access to all OCPDs

[dlukert]

I have recently encountered this requirement that I was unaware of and am having trouble understanding the intent and how it should apply to most buildings. I can think of several buildings I've designed or been in myself, that do not seem to comply with this requirement. The way I read this code, you can't even lock an electrical room with branch circuits, except in specific instances (guest rooms and dorms). Can someone help me understand where I'm going wrong here?

From 2023 NEC:
240.24(B) Occupancy.
Each occupant shall have ready access to all overcurrent devices protecting the conductors supplying that occupancy, unless otherwise permitted in 240.24(B)(1) and (B)(2).
(1) Service and Feeder Overcurrent Protective Devices.
(2) Branch-Circuit Overcurrent Protective Devices.
Where electric service and electrical maintenance are provided by the building management and where these are under continuous building management supervision, the branch-circuit overcurrent protective devices supplying any guest rooms, guest suites, or sleeping rooms in dormitory units without permanent provisions for cooking shall be permitted to be accessible only to authorized management personnel.


How would a commercial office building comply with this? They generally use common electrical rooms and restrict access to tenants in my experience. Some in my office have pointed to 240.24(B)(1), but this only applies to service and feeder OCPDs, not branch circuits.
It seems obvious that this shouldn't apply to a school, daycare or other occupancy with children, or even more obvious would be something like a prison, but there are no exceptions that I can see.

 

[Elect117]

I think most of the points you are making fall under continuous supervision.

But where tenets are concerned, the feeders or branch circuits are accessible by a panel in the rented space or a electrical room on the same floor to which they were provided a key.


And for schools and daycares, the panels or disconnects don't need to be mounted 1' above the ground for the little buggers to reach. They can also be installed in a locked office or locked cabinet so long as someone on site has the key.

 

[hbiss]

How would a commercial office building comply with this?... It seems obvious that this shouldn't apply to a school, daycare or other occupancy with children, or even more obvious would be something like a prison, but there are no exceptions that I can see.

They would have maintenance on premises or at least available within a short timeframe.

-Hal

 

[dlukert]

I think most of the points you are making fall under continuous supervision.

But where tenets are concerned, the feeders or branch circuits are accessible by a panel in the rented space or a electrical room on the same floor to which they were provided a key.


And for schools and daycares, the panels or disconnects don't need to be mounted 1' above the ground for the little buggers to reach. They can also be installed in a locked office or locked cabinet so long as someone on site has the key.

The continuous supervision isn't really a factor I don't think - ready access to branch circuit OCPDs is still required, unless it's a guest room or dorm.

I don't see how a locked electrical room is acceptable unless all occupants are provided with a key.
Unless you take some liberties with how "each occupant" is defined.

I agree with what you're saying regarding schools/daycares, but where is that supported in the code?

 

[dlukert]

They would have maintenance on premises or at least available within a short timeframe.

-Hal

That's not acceptable for branch circuits except dorms and guest rooms in a hotel.

 

[hbiss]

That's not acceptable for branch circuits except dorms and guest rooms in a hotel.

Well, that boils down to the owner's or management's problem to provide someone on duty or on call at all times. If they were collecting rent you can bet there would be someone there real quick.

-Hal

 

[dlukert]

Well, that boils down to the owner's or management's problem to provide someone on duty or on call at all times. If they were collecting rent you can bet there would be someone there real quick.

-Hal

I'm trying to ensure I'm complying with the code - I agree with you in practice, but I am looking for the code to back up what I think we are all used to seeing in actuality.

 

[Elect117]

I don't see how a locked electrical room is acceptable unless all occupants are provided with a key.
Unless you take some liberties with how "each occupant" is defined.

I agree with what you're saying regarding schools/daycares, but where is that supported in the code?

Lets say you have an electrical room on each floor for the subdivided commercial rental spaces (offices). You could 100% provide keys to that room to each renter so they have access to their branch circuit and feeder. It becomes more interesting with services and access to meters.

There is nothing that says you can not lock a panel or closet and just leave the keys in the office. No different than having a bathroom key or even a door key to the rented space.

If you are a renter then you have probably called the maintenance manger (who typically) lives in the building. Or they point to where the keys are in the building and give you a padlock code to get the keys. Like a lock box or locker code for the keys.

I think you are looking for a concrete answer and this rule is one of those that fall under interpreation from the AHJ. There is no definiton for "under continuous building management supervision". That can mean the person lives on site. There is someone in a maintenance room in the building. It could mean the keys are in a lockbox. It could mean the maintenance person is on call 24/7 and has to respond and report to the unit for access. It can mean a bunch of different things.

90% of that is covered by either putting their panel in the unit, having keys provided to the electrical room, or having a lockbox on site with the keys.

 

[jaggedben]

An 'occupant' is not necessarily a person, it is whatever entity is entitled to use and control the space, which might be any kind if organization, or a family, or an individual. Whoever is on the lease, basically. It generally would not include all the persons who might be present in the space and certainly doesn't need to be applied to children or prisoners. It doesn't need to be applied to customers of a retail business either. A business or other organization using a commercial space would be entitled to restrict access of certain areas to certain individuals. In my opinion the NEC only requires that the electrical is constructed such that whoever the organization gives access to does not require access to some other space in the building that they are not entitled to access by their lease or other legal arrangement of occupancy.

A school or a prison would more or less comply automatically because the occupant (e.g. school district organization) would always have access through its employees. The requirement is really aimed at multi-unit buildings where renters (or condo owners, or whatever) only have access to their unit and not the whole building.

 

[dlukert]

Lets say you have an electrical room on each floor for the subdivided commercial rental spaces (offices). You could 100% provide keys to that room to each renter so they have access to their branch circuit and feeder. It becomes more interesting with services and access to meters.

There is nothing that says you can not lock a panel or closet and just leave the keys in the office. No different than having a bathroom key or even a door key to the rented space.

If you are a renter then you have probably called the maintenance manger (who typically) lives in the building. Or they point to where the keys are in the building and give you a padlock code to get the keys. Like a lock box or locker code for the keys.

I think you are looking for a concrete answer and this rule is one of those that fall under interpreation from the AHJ. There is no definiton for "under continuous building management supervision". That can mean the person lives on site. There is someone in a maintenance room in the building. It could mean the keys are in a lockbox. It could mean the maintenance person is on call 24/7 and has to respond and report to the unit for access. It can mean a bunch of different things.

90% of that is covered by either putting their panel in the unit, having keys provided to the electrical room, or having a lockbox on site with the keys.

I'm not following why you think the "under continuous supervision" is the issue here. I don't think it really matters how that is defined or interpreted. Regardless, this only applies to branch circuits in a hotel or dorm, so let's stay in an office setting for the purpose of this discussion.

Two statements here are causing me heartache because these are not defined in NEC:
"Each occupant" and "ready access". It's not clear to me that calling a maintenance guy for access would meet the 'ready access' requirement. 'Each occupant' must be interpreted per jaggedben's response to align with most real world applications, but it doesn't align with how occupant seems to be defined and used elsewhere in the NFPA codes and other building codes.

 

[dlukert]

An 'occupant' is not necessarily a person, it is whatever entity is entitled to use and control the space, which might be any kind if organization, or a family, or an individual. Whoever is on the lease, basically. It generally would not include all the persons who might be present in the space and certainly doesn't need to be applied to children or prisoners. It doesn't need to be applied to customers of a retail business either. A business or other organization using a commercial space would be entitled to restrict access of certain areas to certain individuals. In my opinion the NEC only requires that the electrical is constructed such that whoever the organization gives access to does not require access to some other space in the building that they are not entitled to access by their lease or other legal arrangement of occupancy.

A school or a prison would more or less comply automatically because the occupant (e.g. school district organization) would always have access through its employees. The requirement is really aimed at multi-unit buildings where renters (or condo owners, or whatever) only have access to their unit and not the whole building.

This makes the most sense to me so far, but I still don't know how to interpret 'ready access'. Does calling an off-site maintenance person and having them come unlock a door constitute 'ready access' for example?

I will also say, even though 'occupant' is not defined in NFPA 70. 'Occupancy' and 'Occupant Load' are defined in NFPA 101 and 'occupant' is used throughout NFPA codes. Everywhere else in the code I am aware of, the term 'occupant' is used for any person that will occupy the space - this would certainly include any children or prisoners in a space.

 

[jaggedben]

...'Each occupant' must be interpreted per jaggedben's response to align with most real world applications, but it doesn't align with how occupant seems to be defined and used elsewhere in the NFPA codes and other building codes.

Not sure what makes you say that. The NEC doesn't define 'occupant' nor the IBC or IRC so far as I can tell.

 

[dlukert]

Not sure what makes you say that. The NEC doesn't define 'occupant' nor the IBC or IRC so far as I can tell.

Per 2021 NFPA 101

Occupant Load
The total number of persons that might occupy a building or portion thereof at any one time.

The mechanical code uses the number of occupants to determine ventilation rates as well - in that instance, occupants are defined as each person within the space.

 

[hbiss]

I'm trying to ensure I'm complying with the code

I think you are making way too much out of this. As an engineer and contractor, all you can do is locate and install the equipment in the electrical rooms. 240.24(B) is not the engineers or contractors' responsibility to implement or enforce. So, there is no code for you to comply with. That part is up to the owner. IMO 240.24(B) should be a FPN since it's good advice but unenforceable by the AHJ from the standpoint of the designers and contractors.

-Hal

 

[tortuga]

I have been hit with this several times when dividing up tenant spaces, it can be quite a expensive item for an estimator to overlook.

 

[Elect117]

I'm not following why you think the "under continuous supervision" is the issue here. I don't think it really matters how that is defined or interpreted. Regardless, this only applies to branch circuits in a hotel or dorm, so let's stay in an office setting for the purpose of this discussion.

Two statements here are causing me heartache because these are not defined in NEC:
"Each occupant" and "ready access". It's not clear to me that calling a maintenance guy for access would meet the 'ready access' requirement. 'Each occupant' must be interpreted per jaggedben's response to align with most real world applications, but it doesn't align with how occupant seems to be defined and used elsewhere in the NFPA codes and other building codes.

I see.

Well every occupant does have ready access. Just walk into a bank and ask to see their panel.

But in all honesty, I think people interpret that to mean the people who have a legal claim to the space like a renter or owner.

 

[jaggedben]

This makes the most sense to me so far, but I still don't know how to interpret 'ready access'. Does calling an off-site maintenance person and having them come unlock a door constitute 'ready access' for example?

See the definition of 'accessible, readily' and note what it and the IN say about keys.

I think the off-site person is what this code section is mostly trying to avoid but my point is that as long as *someone* in any group of people who should be accessing the building has the key then that is fine. I do not think the NEC here is trying to legislate that all people who might be present in a building possess all keys necessary to open all doors in the building. But it is trying to ensure that no one has to trespass into an area that might be private to another occupancy in order to reach OCPDs.

 

[tortuga]

Just walk into a bank and ask to see their panel.

Now say a bank that owns a large building wants to down size its first floor customer service area and break off some space to create three small retail tenant spaces, utilities will be included in the rent so no feeder panels, but now the tenants have to access their breakers in the back in the bank.

 

[Elect117]

Now say a bank that owns a large building wants to down size its first floor customer service area and break off some space to create three small retail tenant spaces, utilities will be included in the rent so no feeder panels, but now the tenants have to access their breakers in the back in the bank.

So long as the panel is in the vault, with all the gold / cash, and they don't care that I come in every now and again when rent is due. lol

 

[tortuga]

Another pitfall would be a large resort property with individual dwellings scattered about, think ranch type resort or YMCA retreat center with about 100 dwellings that are rented there is one large 7200V service to the property, everything else is feeders.
240.24(B)(1) requires each house to have access to the service of the property, which would be a 7200V service.
There are been code change proposals around this to add dwelling units to 240.24(B)(1) but they got rejected.