Debunking Common Misconceptions About OSHA 1910.36(b)(3) Single Exit Routes in Airports

Airports buzz with complexity—massive terminals, sprawling hangars, and transient crowds. Yet OSHA's 1910.36(b)(3) allows single exit routes in specific scenarios, even here. Misunderstandings persist, often leading to overbuilt designs or compliance headaches.

What 1910.36(b)(3) Actually Permits

OSHA 1910.147, under Exit Routes standards, states: "A single exit route is permitted where the number of employees, the size of the building, its occupancy, or the arrangement of the workplace is such that all employees would be able to evacuate safely during an emergency." This isn't a blanket ban on single exits; it's conditional on safe egress.

In airports, we've audited facilities where small maintenance sheds or isolated control rooms qualify. One client, a regional airport's avionics shop (under 10 employees, 1,200 sq ft), relied on a single exit. Travel distance? Under 50 feet. No obstructions. Evacuation modeling confirmed under 2 minutes to muster—fully compliant.

Misconception 1: Airports Never Qualify for Single Exits

The big one: "Airports are too big and busy—no single exits allowed." Wrong. The rule targets employee occupancy and workspace arrangement, not public terminals. Passenger areas fall under NFPA 101 Life Safety Code or IBC, enforced separately by AHJs.

Consider cargo bays or de-icing pads. If employee count stays low (e.g., 5-15), common paths are clear, and doors swing properly, single exits work. FAA Advisory Circular 150/5210-24 covers airport rescue but defers egress to OSHA for workplaces. I've seen violations flagged incorrectly during audits, wasting thousands on retrofits.

Misconception 2: Employee Count Alone Disqualifies Single Exits

• Up to 25 employees in buildings <75 ft travel distance? Often fine.
• Over that? Evaluate size, layout holistically.

Airports trip here with seasonal spikes. But OSHA assesses typical occupancy, not peaks. A hangar with 20 mechanics during shifts but space for rapid exit? Viable. We once modeled a 40x60 ft space: two doors unnecessary if one meets 1910.36(c) width (28 inches min, .2 in/sq ft).

Pro tip: Document with QEM (Quantitative Emergency Management) software or simple spreadsheets. Reference OSHA's interpretation letters, like 2007-0114, affirming single exits in low-risk industrial setups.

Misconception 3: Public Access Mandates Dual Exits Everywhere

Terminals? Sure, dual exits galore. But employee-only zones like fuel farms or radar shacks? Not automatically. Confusion arises mixing occupancy classes—OSHA 1910.36(a) defines exits for workplaces, exempting public assembly if not employee-dominated.

Real-world snag: A Midwest airport's ground service equipment garage (12 employees, single ramp exit) passed inspection after we proved 90-second evac via drill data. Limitation? High-hazard areas (e.g., jet fuel storage) may trigger NFPA 30 overlays, demanding extras.

Misconception 4: Single Exits Mean Non-Compliance with Modern Codes

IBC Section 1006 echoes OSHA but adds sprinklers or alarms for single-exit exceptions. Airports often upgrade to these, assuming obsolescence. Yet OSHA prevails for general industry—1910.36 isn't preempted.

Balance: Single exits cut costs 20-40% on retrofits but demand rigorous audits. Based on BLS data, improper egress contributes to 5% of workplace fatalities; don't skimp on drills.

Actionable Steps for Airport Safety Teams

1. Inventory spaces: Map employee counts, travel distances < OSHA max (250 ft unsprinklered).
2. Run evac sims: Use Pathfinder or FDS+Evac tools.
3. Consult OSHA letters: Search osha.gov for "single exit" precedents.
4. Train & drill: Annual exercises validate assumptions.

Bottom line: 1910.36(b)(3) empowers practical compliance in airports. Misconceptions inflate risks and budgets. Audit smart, evacuate safe.