110.26 Egress questions

[mull982]

In trying to get my head wrapped around the NEC egress requirements and had a few questions related to requirements of 112.26.

1) When "working space" is referenced does this only refer to energized parts that will be exposed for maintenance? For example would the rear of LV or MV switchgear require a "working space" if it will never be opened while energized?

2) I believe that any dead front assemblies such as panelboard or switchboard don't typically have any working space requirements on the side or rear?

3) If I understand 110.26(C)(1) correctly is this saying that as long as the required working space (working space defined in 110.26A) is maintained in front of all accessible covers then only one means of egress is required. For example if I had a LV 480V Switchgear lineup with the rear being 3'-6" from the wall (Condition 2) and nothing in front of it within 6ft lets say than it does not matter where in the room the egress door is located? Is there any requirement on the sides of the gear in terms of egress if it was close to a wall on one side?

4) For 110.26(C)(2)(a) with switchgear over 6ft I understand that it must have two means of egress at either end if the normal working spaces are met. So using a similar example above if this switchgear was located 3'-6" from a wall but head a means of egress on either side of the switchgear than i'm assuming that meets the intent. Again does it matter how much space is on the sides of the switchgear to allow egress to exit (say if exits were located towards the front of the lineup on each side)

5) For 110.26(C)(2)(b) in order to have a single means of egress it requires that the double the working distance is met on any accessible parts of the equipment. Continuing with the same example with switchgear against the wall in order to have a single means of egress in front of the switchgear I would need to have double the required working distance in the back of the gear as well as the front (not sure about the sides)

6) I'm trying to understand all of this to determine if the lineup in the attached photo would meet these requirements. With the Switchgear located with the sides against the wall here and the clearances shown does this meet the requirements of 110.26(C)(2)?

Thanks for the help!

 

[charlie b]

I am not sure I understand your questions. Let me start here:

1. You only need working clearance on any side of the equipment for which there is a removable panel so that a person can see directly into the panel interior and possibly do work on something inside. If a side of the equipment is against a wall or does not have a removable cover or panel or door, then you don't need working clearance on that side.
2. You only get into a need for two exits when you have "large equipment." That phrase has been redefined several times over that past decade. In the 2020 NEC, it means 1200 amps or more AND over 6 feet wide.
3. In your PDF, I see two ways of leaving the room. But leaving "the room" is not the requirement. You need two ways to leave the working space. I don't think you have it. If you are standing in front of the two switchgears, right where your PDF says 70", you need to be able to walk left to exit the working space OR walk right to exit the working space. If you try to walk right, you bump into a wall, and can't walk around SWGR 2 on that side.
4. Also, 70" is not twice the minimum required working space of 42". Therefore I don't think your PDF is compliant.

 

[mull982]

I am not sure I understand your questions. Let me start here:

1. You only need working clearance on any side of the equipment for which there is a removable panel so that a person can see directly into the panel interior and possibly do work on something inside. If a side of the equipment is against a wall or does not have a removable cover or panel or door, then you don't need working clearance on that side.
2. You only get into a need for two exits when you have "large equipment." That phrase has been redefined several times over that past decade. In the 2020 NEC, it means 1200 amps or more AND over 6 feet wide.
3. In your PDF, I see two ways of leaving the room. But leaving "the room" is not the requirement. You need two ways to leave the working space. I don't think you have it. If you are standing in front of the two switchgears, right where your PDF says 70", you need to be able to walk left to exit the working space OR walk right to exit the working space. If you try to walk right, you bump into a wall, and can't walk around SWGR 2 on that side.
4. Also, 70" is not twice the minimum required working space of 42". Therefore I don't think your PDF is compliant.

Thanks Charlie your start above his helpful. I'm cant seem to figure out how to put each items in quotes so I'll put follow-up questions below.

1) Understood. So if panel had side covers for access then it would need clearance otherwise not needed like you said. Is there a requirement on how close the side can be to the wall if that area between side and wall is part of egress. In other words I'm assuming this cant be 20" and be considered a means of egress away from working space?

2) Understood. So anything under this criteria only needs one exit and needs to adhere to the required working distances?

3) I understand now that the requirement is for leaving the working area not leaving the room. For these cases I'm assuming the working areas are only considered areas like mentioned in #1 that have access to energized conductors so if these don't exist then obviously there is not requirement to "leave the working area"?

4) So if we had 84" in the front would you consider this to be compliant? Even if we ignore the roll up door as a means of egress and only have the one means of egress.

 

[augie47]

I don't think you are depending on the roll-up door as one of your required means of egress but keep the following in mind:

(3) Personnel Doors. Where equipment rated 800 A or more that contains overcurrent devices, switching devices, or control devices is installed and there is a personnel door(s) intended for entrance to and egress from the working space less than 7.6 m (25 ft) from the nearest edge of the working space, the door(s) shall open in the direction of egress and be equipped with listed panic hardware.

 

[mull982]

To help facilitate the discussion and my understanding I've illustrated a couple of examples in the attached sketch.

1) Scenario 1 - A situation where 110.26(C)(1) would apply. Assuming this is rear accessible switchgear working spaces in front an back would be required as shown. Only the one means of egress is required. Is there a minimum clearance/working space on the sides of the switchgear in this case?

2) Scenario 2 - Again a situation where 110.26(C)(1) would apply. If working distances in the front and back as shown are adequate is this installation ok with the single egress as shown?

3) Scenario 3 - A situation where 110.26(C)(2) would apply. With (2) egress located on both sides of the switchgear and proper working space behind switchgear this would be adequate? Again are there any clearance requirements on the side of the switchgear for egress as shown?

4) Scenario 4 - A situation where 110.26(C)(2)(b) would apply. With double the working distance in the back of the switchgear (as well as the front) would this means of egress with a single door be adequate? I'm curious about what the intent of 110.26(C)(2)(a) is when it refersto an unobstructed egress travel? Does this mean a straight shot with the egress door being in line of site from everywhere on the switchgear?

 

[Carultch]

To help facilitate the discussion and my understanding I've illustrated a couple of examples in the attached sketch.

1) Scenario 1 - A situation where 110.26(C)(1) would apply. Assuming this is rear accessible switchgear working spaces in front an back would be required as shown. Only the one means of egress is required. Is there a minimum clearance/working space on the sides of the switchgear in this case?

2) Scenario 2 - Again a situation where 110.26(C)(1) would apply. If working distances in the front and back as shown are adequate is this installation ok with the single egress as shown?

3) Scenario 3 - A situation where 110.26(C)(2) would apply. With (2) egress located on both sides of the switchgear and proper working space behind switchgear this would be adequate? Again are there any clearance requirements on the side of the switchgear for egress as shown?

4) Scenario 4 - A situation where 110.26(C)(2)(b) would apply. With double the working distance in the back of the switchgear (as well as the front) would this means of egress with a single door be adequate? I'm curious about what the intent of 110.26(C)(2)(a) is when it refersto an unobstructed egress travel? Does this mean a straight shot with the egress door being in line of site from everywhere on the switchgear?

Scenarios 1 and 2 do not count as "large equipment", due to being smaller than 6 ft in width. From what I've seen in practice, this is rare for 1200A equipment. Due to this, only one egress path is strictly required, although it helps to have it on both sides. It is required to have outward-opening doors and listed panic hardware, unless the doors are more than 25 ft from the workspace.

110.26(C)(2) spells out a 24 inch wide egress path on both sides to exit the working space, for "large equipment". Part (1) doesn't spell out a width, for equipment that doesn't count as "large" for the two exits rule, but I wouldn't expect anything smaller than 2 ft to be allowed. That's a tight walkway at just 2 ft in width. I would recommend trying to get at least 3 ft egress paths where you can.

If there is only non-electrical work to be done on the back and/or the sides, 30 inches is the non-energized working space. This assumes all energized work can be done exclusively from a different side. An example is changing air filters, or heating/ventilation maintenance on switchboards/switchgear. Entrance/egress to/from this space would also be 24 inches.

These scenarios also show an inward opening door, which would not meet 110.26(C)(3), unless it is greater than 25 ft from the nearest edge of the working space. The equipment would need to be less than 800A (not inclusive of 800A), in order for 110.26(C)(3) to not apply. There is no dimensional criteria on what qualifies for this rule, so it would apply on just a single 800A switch that is 30 inches wide.

Scenario 3: Any chokepoint in the egress path must be no narrower than 24 inches. Take the inside edges of the doorways, and draw your 24" radius around them. Make sure the floor space is clear of all equipment and housekeeping slabs, so there is a continuous 24" wide floor or wider, to walk to those doors. Also equip with doors with listed panic hardware.

Scenario 4: you have double the workspace on both sides of the switchboard, so you'd only need the exit on one side of each workspace. One way you can strategically make this requirement 72 inches instead of 84 inches, is if you cover block walls with paneling that is non-conductive, such as plywood.