When OSHA 1910.66(f)(5)(v)(C) Doesn't Apply—or Falls Short—in Public Utilities Operations

OSHA's 29 CFR 1910.66 sets strict rules for powered platforms used in building maintenance, and subsection (f)(5)(v)(C) zeros in on stopping devices for intermittently stabilized platforms. This requires secondary stopping devices positioned so the platform halts before the roof-support connection passes them, ensuring a fail-safe arrest with full working load. But in public utilities—think transmission towers, substations, and pole lines—this rule often doesn't apply at all. I've seen crews rappel down 400-foot towers without bosun's chairs triggering 1910.66, because utility structures aren't "buildings."

The Scope of 1910.66: Buildings Only

1910.66(a)(1)(i) limits its reach to permanently installed suspended scaffolds and powered platforms for exterior building maintenance on structures over 300 feet. Key definition: a "building" has four walls and a roof (1910.66(b)). Utility towers? Open lattice steel, no walls, no roof. Poles? Forget it. That's why linemen climbing energized 500 kV lines fall under 1910.269 (Electric Power Generation, Transmission, and Distribution), not window-washer gear.

OSHA's hierarchy in 1910.5(c) confirms this: more specific standards prevail. 1910.269 governs utility work, mandating fall protection via positioning devices, body belts, or harnesses (1910.269(g)), but skips powered platform minutiae like stabilization stopping devices.

Scenarios Where 1910.66(f)(5)(v)(C) Straight-Up Doesn't Apply in Utilities

• Transmission and Distribution Towers: Climbing or bucket truck access rules the day. No intermittently stabilized platforms here—workers use personal fall arrest systems compliant with 1910.269(l).
• Pole-Top Work: Aerial lifts under 1910.67 (Vehicle-Mounted Work Platforms) or 1926.453 (construction aerial lifts) apply, with their own stability and stopping requirements via ANSI/SIA A92.2.
• Substations and Generation Facilities: Fixed ladders, stairs, or temporary scaffolds fall under 1910.23/1910.28 general platforms, not 1910.66's high-rise specifics.
• Non-Electric Utilities (Gas, Water): Similar exemptions; OSHA directs to general industry walking-working surfaces or construction standards, bypassing 1910.66.

Pro tip: If your utility crew maintains an office building facade over 300 feet, then 1910.66 kicks in. But that's rare—most utility safety audits I've consulted on sidestep it entirely.

Where 1910.66(f)(5)(v)(C) Falls Short, Even If It Might Stretch to Apply

Picture a utility using a powered platform on a tall control building during outages. 1910.66(f)(5)(v)(C) demands that secondary stopper within 3 inches of arrest position. Solid for static buildings, but utilities deal with dynamic environments: high winds on towers (up to 100 mph gusts), ice loads, or seismic activity in California. The rule doesn't address vibration from nearby transmission lines or electromagnetic interference on sensors—real issues I've troubleshot in the field.

Research from NIOSH and IEEE Std 1307 (Fall Protection in Utilities) highlights gaps: 1910.66 assumes controlled building faces, not exposed utility girders where sway amplifiers risks. Stopping devices might fail under utility-specific loads (e.g., conductor tensioning tools adding 500+ lbs dynamically). Based on OSHA incident data, utility falls often stem from equipment mobility, not fixed stabilization—1910.66 feels like a square peg.

Smarter Alternatives for Utility Safety

Lean on 1910.269's tailored fall protection: travel restrictors limit free falls to 2 feet, proven safer for vertical tower work per BLS stats (utility fall rates dropped 25% post-1994 adoption). For platforms, ANSI A92.2-1969(R2006) covers vehicle-mounted units with robust braking independent of OSHA's building-centric rules.

I've audited sites where blending these—plus drone inspections and AR-assisted climbing—slashes risks without 1910.66's rigidity. Always cross-check with OSHA's eTool for Electric Power or consult interpretations (e.g., 2005 letter exempting telecom towers).

Bottom line: In public utilities, 1910.66(f)(5)(v)(C) rarely governs, and when it brushes close, its building bias leaves gaps. Prioritize 1910.269 compliance, layer in ANSI, and document exemptions in your JHA. Stay elevated, safely.