Combo units pair an EXIT legend with emergency light heads on one backplate. This guide shows when combinations make the most sense on Chicago projects—doors and intersections, tight retrofits, remote‑head loading, wet‑location use—and what to include in your plan‑review submittal.
Last updated: October 30, 2025
What a combo unit is (and isn’t)
An exit & emergency combo combines a clearly legible EXIT legend and two adjustable emergency heads on one metal backplate, powered from a single set of electronics and battery. For Chicago jobs, favor steel or die‑cast aluminum housings, red legends, universal 120/277 V input, and batteries sized to provide the required 90‑minute duration.
- Is: a single device providing wayfinding + egress illumination, often with remote‑capable outputs.
- Isn’t: a cure‑all. In large open areas or very high ceilings, separate emergency lighting may still be required.
If you’re deciding between a combo and a separate sign + light, base the choice on coverage, wiring simplicity, and maintenance access, not just device count.
When combos are the better choice
Combos excel where you need a visible legend and targeted light in the same spot. Typical winners include:
- Egress doors: place a combo above or adjacent to the door so heads illuminate the landing and initial pathway.
- Intersections & turns: one head covers the near field (10–15 ft) and another the approach (20–30 ft) while the legend shows direction.
- Retrofits: replacing a damaged sign and adding emergency light coverage without opening new raceways.
- Narrow corridors & tight cores: fewer penetrations and cleaner sightlines than separate devices.
- Remote‑capable designs: use the onboard battery to power a nearby remote head where a second device is unavoidable.
For exit‑sign specifics (faces, legends, chevrons), see Chicago‑Approved Exit Signs: Requirements, Options & Submittal Checklist.
When separate devices are smarter
Use discrete exit signs and emergency lights when:
- Large open areas: combos alone may create bright‑dark patterns; add dedicated emergency lights sized for uniformity.
- High ceilings: you need higher output, different optics, or ceiling‑mounted solutions to reach the floor.
- Complex aiming: multiple stairs or obstacles require independent head placement.
- Load margin is tight: remote‑capable combos can be over‑subscribed if they also feed remote heads (see loading below).
For spacing and aiming fundamentals on stand‑alone emergency lights, reference Chicago‑Approved Emergency Lights: Specs, Spacing & Common Inspection Fails.
Design checklist: output, optics & coverage
A good combo layout balances legend visibility with uniform egress illumination. Use this checklist as you plan:
- Housing: steel or die‑cast aluminum (preferred for Chicago jobs) for durability and inspection‑friendly service.
- Legend: red EXIT letters with field‑applied chevrons that match the life‑safety plan.
- Heads: adjustable, with beam spreads appropriate to corridor width and ceiling height.
- Output: ensure both heads can deliver coverage to the landing and along the path; consider one near‑field and one far‑field aim.
- Uniformity: avoid bright/dark oscillation by offsetting units across the corridor or staggering spacing.
- Maintenance: place combos where test switches and indicators are safely accessible from a ladder.
Remote‑head loading & voltage drop
Many combos are remote‑capable—they can drive additional remote heads. Respect the available wattage and plan conductor sizes and lengths to manage voltage drop.
- Budget your watts: subtract the onboard heads’ draw from the unit’s remote‑capable watts to find remaining capacity.
- Conductor length & size: keep runs short where possible; upsize conductors on longer runs to reduce voltage drop.
- Label loads: in the submittal, list the remote heads’ wattage and distances so reviewers see your margin.
- Test under load: during commissioning, run a full discharge with remote heads connected to confirm 90‑minute performance.
Wet‑location & parking‑garage combos
Garages, exterior stairs, and exposed vestibules call for wet‑location, gasketed combos. Use sealed conduit entries, impact‑resistant lenses, and consider cold‑weather packages when ambient temperatures demand.
- Ratings: match NEMA/IP ratings to the environment and preserve them during installation.
- Hardware: tamper‑resistant screws where vandalism is a concern.
- Access: place units for safe testing in traffic areas (near guardrails or away from vehicle paths).
Deeper guidance on ratings, mounting, and field troubleshooting is covered in Wet‑Location in Chicago: NEMA/IP Ratings, Mounting, and Field Troubleshooting.
Mounting, sightlines & chevrons
Mount combos where both the legend and beams do the most good. Above doors, ensure the heads can aim down the landing and into the corridor. At T‑intersections, confirm the legend is visible from both approaches.
- Wall mount: typical for doors; avoid door swings that block visibility or aim.
- End mount: good in corridors requiring visibility from both directions; verify clearance from sprinklers and diffusers.
- Ceiling mount: where partitions or glazing block wall locations; ensure adequate structure for the backplate.
- Chevron accuracy: apply left/right/double arrows to match life‑safety drawings—document choices in the schedule.
Plan‑review submittal checklist
Use this paste‑ready list on your cover sheet to speed approvals:
- Cut sheets highlight: UL 924, metal housing (steel or die‑cast), red EXIT legend, 90‑minute runtime, remote‑capable wattage (if applicable).
- Fixture schedule: part numbers; input voltage (120/277 V); mounting (wall/ceiling/end); chevron orientation; head output/beam notes.
- Egress drawings: show locations at doors/intersections; indicate aiming arrows for heads; identify any remote heads driven by combos.
- Environment notes: call out wet‑location or cold‑weather combos for garages/exterior stairs.
- Electrical one‑line: unswitched circuiting and remote‑head loads with distances and conductor sizes.
- Maintenance plan: monthly function, annual 90‑minute test, and recordkeeping method.
Maintenance & testing cadence
Adopt a simple routine so combos are inspection‑ready:
- Monthly: push‑to‑test each unit; verify both heads illuminate the intended areas; check legend visibility and chevrons.
- Annually: perform a 90‑minute discharge; confirm recharge times; replace aging batteries proactively.
- Logs: keep a floor/room index so inspectors can trace results quickly.
Common inspection pitfalls—combos
- Using non‑metal cabinets where durability is expected on Chicago jobs.
- Under‑lighting stairs or turns by assuming the combo’s heads cover too much area.
- Remote‑head loading that exceeds available watts or suffers excessive voltage drop.
- Incorrect chevrons at decision points; missing double‑arrow at T‑intersections.
- Wet‑location ratings compromised by unsealed conduit entries.
- Missing monthly/annual test records at inspection.
Quick scenarios & recommendations
Use these patterns as a starting point; verify with your drawings and photometrics.
- Door to exterior (vestibule): one combo above the door; heads aim at landing and first 20–30 ft of path. If vestibule is damp, specify wet‑location model.
- T‑intersection: end‑mounted combo centered in corridor; double‑arrow chevrons; heads aimed left/right along each branch.
- Narrow retrofit corridor: replace failing sign with a combo; use remote‑capable output to feed a small remote head around the corner.
- Garage exit stair: wet‑location combo adjacent to the egress door; heads aimed across the drive aisle and onto the stair landing.
For a deeper foundation on spacing and aiming technique, review Chicago‑Approved Emergency Lights: Specs, Spacing & Common Inspection Fails.
Resources
FAQ
Are combos allowed everywhere a separate sign + light would be used?
Often, yes—especially at doors and intersections. In large open areas or high ceilings, you may still need dedicated emergency lights for uniform coverage.
Can a combo power remote heads?
Many can. Verify the unit’s remote‑capable wattage, conductor sizes, and run lengths to control voltage drop and preserve the 90‑minute duration.
Do wet‑location combos differ from indoor models?
Yes. They use gasketed housings, sealed entries, and impact‑resistant lenses. In cold environments, add a cold‑weather package if required.
What should I highlight in my submittal?
UL 924 listing, metal housing, red legend with correct chevrons, 90‑minute runtime, head output/aiming notes, any remote‑head loading, and environment ratings (wet/cold).