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Generation vs. Transmission/Distribution Power generation vs. transmission/distribution

The "269" standard does not define generation, transmission, and distribution, since generally the same rules apply to all of these systems. The most pronounced difference between generation versus transmission and distribution facilities in the "269" standard are the two separate sets of hazardous energy control or lockout/tagout requirements—one for generation and one for transmission and distribution. Because of these differences, OSHA's Compliance Directive for 1910.269 (CPL 02-01-038, Appendix B, Item 2) provides guidance and flexibility for deciding where generation stops and transmission/distribution begins. As discussed in this compliance directive:
  • A dividing point must be established between generation versus transmission/distribution.
  • The dividing point must be consistently applied throughout a facility.
  • Workers must be trained on the precautions they need to use on either side of the dividing point.
At most facilities, the dividing point between generation and transmission/distribution is usually the disconnect on the output side of the generator's step-up transformer (i.e., the high-side disconnect of the unit transformer).

Generation
The general requirements of the "269" standard apply to generation. 1910.269(v) includes specific additional requirements for generating facilities, some of which apply to specific operations and equipment used to generate the electricity. Some of the main generation requirements in 1910.269(v) include:
  • Interlocks and other safety devices must be maintained in a safe, operable condition (29 CFR 1910.269(v)(1)(i)).
  • Generator or exciter brushes may not be changed while the generator is running if a ground condition exists (29 CFR 1910.269(v)(2)).
  • Access to areas containing exposed electrical equipment must be enclosed, posted with warning signs, and locked (if not continuously attended) to prevent access by 269-unqualified employees (29 CFR 1910.269(v)(4)(ii), (iii), and (iv)).
  • Sufficient access and working space must be maintained around all electrical equipment (29 CFR 1910.269(v)(3)).
  • Uninsulated live parts operating at more than 150 volts to ground that are not located so as to provide safe clearance from accidental contact must be guarded (29 CFR 1910.269(v)(5)(i)).
Transmission vs. Distribution
Substations
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