Why Exit Sign Spacing Matters
Proper exit sign spacing ensures occupants can always see the path to safety, even in smoke-filled or low-visibility conditions. Both OSHA and NFPA have specific requirements for exit sign placement that must be reflected on your evacuation maps. Getting the spacing right is critical for compliance and, more importantly, for saving lives during actual emergencies. Your evacuation map should show all exit sign locations to verify adequate coverage throughout your facility.
OSHA Exit Sign Requirements (29 CFR 1910.37)
- Exit signs required where exit location is not immediately obvious
- Signs must be visible from all directions of exit access
- Illuminated signs readable in both normal and emergency conditions
- Letters must be at least 6 inches high with 3/4 inch stroke width
- Word "EXIT" must be clearly distinguishable
- Signs cannot be obscured by decorations or other objects
- Doors or passages that could be mistaken for exits must be marked "NOT AN EXIT"
NFPA Exit Sign Spacing Rules (NFPA 101)
- Exit signs visible within 100 feet viewing distance (standard)
- Reduced distance for externally illuminated signs (may require 75 ft)
- Signs required at every exit and exit access doorway
- Directional signs where exit path is not immediately apparent
- Signs mounted with bottom edge 80 inches or less above floor
- Floor-proximity signs required where smoke may obscure ceiling signs
- Emergency power backup for 90 minutes minimum
Exit Sign Height and Placement Checklist
- Bottom of sign no more than 80 inches above finished floor
- Signs visible from corridors in both travel directions
- Directional arrows point toward nearest exit when path turns
- Signs placed above or beside each exit door
- No obstructions blocking visibility of any exit sign
- Supplemental floor-level signs in high-hazard occupancies
- Signs at stairwell entries on each floor
- Signs visible upon entering corridors from rooms
Understanding Visibility Requirements
NFPA 101 requires that exit signs be visible within 100 feet of viewing distance for internally illuminated signs. This means in any corridor longer than 100 feet, you need multiple exit signs to maintain continuous visibility. Signs must also be visible from perpendicular corridors and at turning points. When planning your evacuation map, place exit signs at corridor intersections, above exit doors, and at maximum 100-foot intervals along long corridors. Floor-proximity exit signs (mounted within 18 inches of floor) are required in certain occupancies where smoke accumulation may obscure standard ceiling-height signs.
Exit Sign Placement by Facility Type
Office Buildings
- Signs at each corridor intersection
- Visible from all workstation clusters
- Above each stairwell and elevator lobby
- Directional signs where open floor plans obscure exit view
Warehouses
- Signs visible above maximum racking height
- Additional signs at aisle intersections
- Illuminated signs in areas with minimal natural light
- Consider photo-luminescent signs as backup
Retail
- Signs visible above merchandise displays
- Extra signs in stockroom and back-of-house areas
- Directional signs guiding customers to public exits
- Signs at fitting rooms and restroom corridors
Common Exit Sign Violations
Frequently cited violations include: Signs spaced more than 100 feet apart in corridors. Signs mounted too high (above 80 inches). Obstructed visibility from decorations, signage, or merchandise. Failed emergency lighting backup (must illuminate for 90 minutes). Missing directional arrows at corridor turns. Doors to storage rooms not marked "NOT AN EXIT" when near actual exits.
Exit Sign Quick Reference
Standard spacing for internally illuminated signs
OSHA minimum for exit sign lettering
Required emergency illumination duration
Maximum height for floor-proximity signs
Your evacuation map should show every exit sign location. This serves two purposes: it verifies adequate spacing coverage during your compliance review, and it helps employees quickly confirm they are following marked routes during an evacuation. Use a distinct symbol for exit signs in your legend and ensure they align with your actual installations.