Under 1926.1409, which power lines are covered by the "Power line safety (over 350 kV)" rule?
This section applies to power lines that are over 350 kV (i.e., greater than 350 kilovolts). For the rule text see 1926.1409.
OSHA 1926.1409
Power line safety requirements
Subpart CC
Questions & Answers
Under 1926.1409, do the requirements of 1926.1407 and 1926.1408 apply to these high-voltage power lines?
Under 1926.1409(a), what clearance distance must I use when working near power lines at or below 1000 kV?
For power lines at or below 1000 kV, you must substitute "50 feet" wherever the distance "20 feet" is specified in the applicable requirements. See 1926.1409(a).
Under 1926.1409(b), who establishes the minimum clearance distance for power lines over 1000 kV?
For power lines over 1000 kV, the minimum clearance distance must be established by the utility owner/operator or by a registered professional engineer who is a qualified person with respect to electrical power transmission and distribution. See 1926.1409(b).
Under 1926.1409, if a power line is 500 kV, what clearance distance should I assume where 1926.1407 or 1926.1408 say "20 feet"?
If the power line is 500 kV (which is at or below 1000 kV), you must use "50 feet" wherever the rules specify "20 feet." This substitution is required by 1926.1409(a).
Under 1926.1409, if a power line is 1200 kV, how do I determine the minimum safe clearance distance?
If the power line is over 1000 kV (for example, 1200 kV), the minimum clearance distance must be established by the utility owner/operator or a registered professional engineer who is a qualified person for electrical transmission/distribution pursuant to 1926.1409(b).
Under 1926.1409, does the substitution in (a) (20 feet → 50 feet) apply to every place in 1926.1407 and 1926.1408 that says "20 feet"?
Yes — 1926.1409(a) directs that for power lines at or below 1000 kV you must substitute "50 feet" wherever the distance "20 feet" is specified in the applicable requirements (i.e., the provisions in 1926.1407 and 1926.1408).
Under 1926.1409, does this section change any other safety duties in 1926.1407 or 1926.1408 besides the specified distance substitutions and the >1000 kV rule?
No — 1926.1409 only modifies the application of 1926.1407 and 1926.1408 by (a) substituting "50 feet" for "20 feet" for lines at or below 1000 kV and (b) requiring that minimum clearances for lines over 1000 kV be established by the utility owner/operator or a qualified registered professional engineer; otherwise the referenced requirements continue to apply as written (see 1926.1409).
Under 1926.1409, can an employer use a smaller clearance than 50 feet when working near a 900 kV power line?
No — for power lines at or below 1000 kV the rule requires substituting "50 feet" wherever "20 feet" appears, so an employer may not rely on the smaller 20-foot clearance in those places. See 1926.1409(a).
Under 1926.1409, does this section apply to power lines that are exactly 350 kV?
No — the section title and text refer to power line safety "over 350 kV," so 1926.1409 applies to lines above 350 kV (i.e., greater than 350 kV), not to lines that are exactly 350 kV. See 1926.1409.
Under 1926.1409, if the utility owner establishes a clearance distance for a line over 1000 kV, do employers and their operators have to follow it?
Yes — when 1926.1409(b) requires the utility owner/operator or a qualified registered professional engineer to establish the minimum clearance for lines over 1000 kV, employers and workers must follow that established clearance as the applicable minimum.
Under 1926.1409, does the phrase "qualified person with respect to electrical power transmission and distribution" change who may establish clearances for >1000 kV lines?
Yes — for lines over 1000 kV the minimum clearance must be set either by the utility owner/operator or by a registered professional engineer who is a qualified person for electrical power transmission and distribution, per 1926.1409(b). This places responsibility for establishing safe clearances with those having the appropriate technical authority and qualifications.
Under 1926.1409, where should I look for the operational details (work practices, controls) that apply once the applicable clearance distance is known?
Under 1926.1409, if a project involves multiple lines with different voltages (some below and some above 1000 kV), how do I apply the clearance rules?
Apply the rule for each line based on its voltage: for lines at or below 1000 kV use the substituted "50 feet" wherever the text specifies "20 feet" per 1926.1409(a), and for lines over 1000 kV use the minimum clearance established by the utility owner/operator or a qualified registered professional engineer per 1926.1409(b).