110.26: DON'T BE THAT GUY WHO PUTS THE PANEL BEHIND THE WATER HEATER

The "Give Yourself Room to Work (and Run)" Rule

Look, we've all been there. You roll up to troubleshoot a tripped breaker and find the panel buried behind grandma's Christmas decorations, a stack of 2x4s, and what appears to be a 1987 exercise bike that's never been used. Or worse—you open a panel door and BAM, it hits the shelving unit someone installed 18 inches away because "there was space there."

110.26 is the NEC's way of saying: "Hey Einstein, leave some room to work without becoming a statistic."

This section is all about working clearances—the sacred space around electrical equipment that keeps you from getting Kentucky-fried when things go sideways. It covers how much elbow room you need, how tall that space needs to be, whether you can escape without doing a Superman dive, and keeping Karen from HR from stacking file boxes in front of the main switchgear.

The Real-World Breakdown

Working Space Dimensions: The Three Amigos

You need to think in three dimensions here (I know, I know—geometry class haunts us all):

DEPTH (how far back you stand from the gear):

• Check Table 110.26(A)(1)—it's your new best friend
• Condition 1: 3 feet minimum (live parts on one side, nothing sketchy on the other)
• Condition 2: 3 feet up to 3½ or 4 feet depending on voltage (live parts on one side, grounded stuff like a concrete wall on the other)
• Condition 3: 3 feet up to 4 or 5 feet depending on voltage (live parts on BOTH sides—aka the "this is fine" meme with the dog in the burning room)

Here's the kicker: Condition 2 assumes concrete, brick, or tile walls are grounded. So that panel 3 feet from a concrete wall? That's Condition 2, friend. You need 3½ feet for 277V circuits, not 3 feet.

WIDTH:

• 30 inches OR the width of the equipment, whichever is GREATER
• Equipment doors must open at least 90 degrees
• If opened doors block your access down to less than 24 inches wide, you failed

Think of it like this: You should be able to stand in front of a panel with your arms out like you're doing the YMCA dance (the "Y" part) without touching stuff that'll bite you.

HEIGHT:

• 6½ feet tall OR the height of the equipment, whichever is GREATER
• Measured from the floor up
• That concrete pad under the equipment? Can stick out 6 inches max beyond the front
• Meters can stick out past this—they get a hall pass

Exception for us dinosaurs: In existing houses, panels and service equipment 200A or less get a break if the ceiling's lower than 6½ feet. (Because apparently, people in 1952 were hobbits.)

The "Oh Crap, I Need to Get Out of Here" Rules (Entrance and Egress)

Basic rule: You need at least ONE way in/out of the working space. Groundbreaking stuff, right?

But here's where it gets spicy—LARGE EQUIPMENT (the stuff that'll really wreck your day):

You need TWO ways out (one at each end) when you've got:

• Equipment rated 1200A or more AND over 6 feet wide, OR
• Multiple disconnects per 225.33(A) or 230.71(B) that add up to 1200A or more AND over 6 feet wide combined

Each exit must be at least 24 inches wide and 6½ feet tall.

"But wait," you say, "I've seen big gear with one way out!"

You can get away with one exit if:

• (a) Unobstructed egress: The space lets you continuously haul ass away from the arc flash without hitting a wall (think of a long lineup of gear where you can run sideways), OR
• (b) Extra working space: You've got TWICE the working depth from Table 110.26(A)(1), and the entrance is positioned so you're never farther from it than the table requires

The Panic Hardware Rule (new-ish and critical):

• Equipment 800A or more with OCPDs, switches, or controls
• Personnel doors within 25 feet of the working space
• Doors must open at least 90 degrees in the direction of egress
• Doors must have listed panic hardware or fire exit hardware

Translation: When stuff goes sideways and you need to exit stage left at Mach 2, you hit that crash bar and GO. No fumbling with doorknobs while your eyebrows are on fire.

Dedicated Space: "No, You Can't Store Your Lunch There"

INDOORS (110.26(E)(1)):

You get a dedicated electrical zone:

• Width and depth of the equipment
• Floor to 6 feet above the equipment OR to the structural ceiling (whichever is LOWER)

In this zone, NOTHING foreign to the electrical installation is allowed—no:

• Plumbing pipes (unless sprinkler pipes installed per code)
• HVAC ducts
• Karen's filing cabinet
• Bob's "temporary" storage of drywall

Exception: Drop ceilings with removable panels are okay in the 6-foot zone. (Because how else would you access the equipment?)

Above the 6-foot dedicated space, other systems are allowed IF you protect the electrical gear from leaks, condensation, or "oops, I broke the water line" scenarios.

OUTDOORS (110.26(E)(2)):

Same deal:

• Dedicated zone from grade to 6 feet above, matching the equipment width/depth
• No piping, no other equipment
• Working clearance space (from 110.26(A)) must be kept clear—no architectural BS or other equipment
• Gotta protect it from vehicular traffic (unless you enjoy replacing gear that pickup trucks have assaulted) and accidental spills from piping

Exception: Roof overhangs or structural extensions can invade the zone. (Your building's eave won't electrocute anyone.)

Storage and Illumination: Common Sense That Needs to Be Written Down

110.26(B)—Clear Spaces: The working space is NOT A STORAGE LOCKER. I don't care if it's "just for a minute" while the drywall's being delivered. Clear means CLEAR.

110.26(D)—Illumination: All indoor working spaces around service equipment, switchboards, switchgear, enclosed panelboards, or MCCs need lights. And here's the part that trips people up: You CANNOT control those lights by automatic means only (like motion sensors or timers that shut off automatically).

Why? Because when you're elbow-deep in a 480V panel and the motion sensor decides you're not moving enough, you don't want the lights going off. You can have a switch, you can have a receptacle with a lamp plugged in (if you meet the dwelling unit exception), but NO auto-only.

The Attic/Crawlspace Special (Limited Access)

110.26(A)(4) covers equipment in tight spaces (because someone always wants to stick a panel where it doesn't belong):

Requirements:

1. Access opening minimum 22" × 22" (lay-in ceiling) or 22" × 30" (crawl space)
2. Working space width: 30 inches or equipment width, whichever is greater
3. Doors must open 90 degrees minimum
4. Depth per Table 110.26(A)(1), unobstructed by cabinets/walls/partitions down to the floor
5. Height: Whatever's necessary to install/service the equipment (they're cutting you a break here because, you know, it's an attic)
   • Ceiling structural members or access panels are allowed, but can't require more than a 6-inch side reach into the enclosure

Basically: If you're gonna put a panel in the attic, at least make it so the poor electrician can reach it without joining Cirque du Soleil.

KEY TAKEAWAYS (The Stuff That'll Save Your Bacon)

⚡ Table 110.26(A)(1) is GOSPEL—memorize it or tattoo it on your arm:

• 0-150V: 3 feet for all conditions
• 151-600V: 3 feet / 3½ feet / 4 feet (Conditions 1/2/3)
• 601-1000V: 3 feet / 4 feet / 5 feet (Conditions 1/2/3)

⚡ Condition 2 is THE TRAP—concrete, brick, and tile walls are considered GROUNDED. Panel facing a concrete wall = Condition 2.

⚡ Width = 30" or equipment width, whichever is GREATER. Doors must open 90°.

⚡ Height = 6½ feet or equipment height, whichever is GREATER (with that 200A dwelling unit exception for existing installs).

⚡ TWO exits required for equipment ≥1200A AND >6 feet wide (or combined disconnects meeting same criteria), UNLESS you have unobstructed egress or double working depth.

⚡ Panic hardware required on personnel doors within 25 feet of working space for equipment ≥800A.

⚡ Dedicated space = floor to 6 feet (or structural ceiling) above equipment, full width and depth. NO foreign systems in this zone (with exceptions for sprinklers and drop ceilings).

⚡ NO STORAGE in working spaces. Ever. Not even "just for a second."

⚡ Illumination required for indoor service equipment, switchboards, switchgear, enclosed panels, and MCCs. CANNOT be automatic-only control.

⚡ Dead-front assemblies don't need working space in back/sides if everything's accessible from the front. (But you need 30" for mechanical access to non-electrical stuff.)

REAL-WORLD SCENARIOS (Tales from the Jobsite)

Scenario 1: The Home Depot Guy's Special

You're doing a service change in a garage. Homeowner says, "Can you put the new 200A panel right here?" and points to a spot 18 inches from his workbench that's bolted to the concrete wall.

WRONG. That's Condition 2 (concrete wall = grounded), 240/120V service (151-600V range). You need 3½ feet minimum, and the width needs to be 30 inches, which the workbench is blocking.

RIGHT: Move it over so you have 3½ feet from the panel to the workbench, with 30" of width. Or tell him the workbench needs to relocate. His call, but it's gotta be code-compliant.

Scenario 2: The "It Fit There Yesterday" Trap

You're installing a new 1600A service switchgear that's 8 feet wide in a mechanical room. There's one door into the room, located near one end of the gear.

WRONG. This is >1200A AND >6 feet wide. You need two exits, one at each end of the working space, each at least 24" wide × 6½' tall.

RIGHT: You need a second personnel door at the other end, OR you demonstrate unobstructed egress (can run sideways away from gear continuously), OR you provide double the Table 110.26(A)(1) working depth and position the single entrance per 110.26(C)(2)(b).

Oh, and if there's ANY personnel door within 25 feet? Better have panic hardware on it.

Scenario 3: The Drop Ceiling Disaster

Architect puts an MCC in a room with a drop ceiling at 7 feet. Equipment is 7½ feet tall. HVAC contractor runs a supply duct 5 feet above the floor, right over the MCC's front.

WRONG. The working space height must be 7½ feet (equipment height > 6½ feet). The duct at 5 feet is blocking the required working space. Also, the dedicated space extends to 6 feet above the equipment (7½' + 6' = 13½' up) or to the structural ceiling, whichever is lower—if that structural ceiling is above 7½ feet, the duct can't be in the first 6 feet of that zone at all without protection from leaks.

RIGHT: Reroute the duct. HVAC guy will grumble, but he'll get over it. Electrical equipment working space trumps "but I already installed it."

Scenario 4: The Attic Panel Nightmare

You're installing a subpanel in an attic. Access hatch is 18" × 24". Panel is mounted on the side of a truss with another truss 28 inches away. No light up there.

WRONG on multiple counts:

• Access opening needs to be minimum 22" × 30" for a crawl space/attic
• Working space width needs to be 30 inches minimum—that 28" between trusses isn't enough
• You need illumination—no light = violation

RIGHT: Enlarge the hatch to 22" × 30" minimum, move the panel or the truss (good luck) so you have 30" minimum width, install a light that's not on automatic-only control. Or, you know, DON'T put a panel in the attic unless you really have to.

Scenario 5: The Industrial Motion Sensor Fiasco

You're finishing a commercial job. Electrical room has the 800A service switchgear. GC installs fancy motion-sensor lights to "save energy."

WRONG. The illumination for working spaces around service equipment, switchboards, etc., cannot be controlled by automatic means only. Motion sensors that shut off automatically don't cut it.

RIGHT: Install a switch (manual control) or have the motion sensor wired so it can't turn off automatically while someone's working. The point is, YOU control when those lights go off, not some sensor that thinks you've been standing still too long while you're reading a one-line diagram.

WHAT TO STUDY (Exam Gold)

Master and Journeyman exams LOVE this section. Here's what shows up repeatedly:

Must-Know for Exams:

1. Table 110.26(A)(1)—Cold

   • They'll give you a voltage and a condition; you pick the depth
   • Watch for: "Panel 3 feet from concrete wall"—that's Condition 2!

2. Working Space Dimensions:

   • Width = 30" or equipment width, greater of
   • Height = 6½ ft or equipment height, greater of
   • Depth = per Table 110.26(A)(1)

3. The Two-Exit Rule:

   • When: ≥1200A AND >6 ft wide (or combined disconnects same)
   • Exceptions: unobstructed egress OR double depth
   • Exit size: 24" wide × 6½ ft tall minimum

4. Panic Hardware:

   • Equipment: ≥800A with OCPDs/switches/controls
   • Doors within: 25 feet of working space
   • Must: open ≥90° toward egress, have listed panic/fire exit hardware

5. Dedicated Space:

   • Indoor: floor to 6 ft above equipment (or structural ceiling, lower)
   • Outdoor: grade to 6 ft above equipment
   • Width/depth: matches equipment
   • No foreign systems (with sprinkler/drop ceiling exceptions)

6. Illumination Requirements:

   • Where: service equipment, switchboards, switchgear, enclosed panelboards, MCCs (indoors)
   • Control: NOT automatic means only

7. Condition Definitions:

   • Condition 1: live one side, nothing sketchy other side
   • Condition 2: live one side, grounded other side (concrete/brick/tile = grounded!)
   • Condition 3: live both sides

8. Common Exam Tricks:

   • "Can you store materials in working space?" (NO, never)
   • "Panel is 24" wide, what's minimum working width?" (30", not 24")
   • "Equipment is 5 ft tall, what's minimum working height?" (6½ ft, not 5 ft)
   • Calculating egress requirements for various ampacities/widths

THE BOTTOM LINE