Portable cords must be size 12 AWG or larger Type G, PPE, S, SE, SEO, SEOO, SC, SCE, SCT, SO, SOO, ST, STO, STOO, W or other types identified for extra-hard usage and must be of the grounding type. The cord type is printed or embossed on approved cords. Two-wire cords. Note to paragraph (a): This section covers grounding of transmission and distribution lines and equipment when this subpart requires protective grounding and whenever the employer chooses to ground such lines and equipment for the protection of employees. For any employee to work. Temporary electrical installations on construction sites are commonly the most cited by OSHA during routine and focused inspections. 451 General Requirements, 1926. 405 Wiring Methods. work requires electrical power for many purposes. However, exposure to weather, frequent relocation, rough use and other condi-tions not normally encountered with conventional wiring systems necessitate special consideration not require in other applications or in completed structures. Electricity doesn't. This Guide designates the practices that should be followed by the member firms of the Infrastructure Health & Safety Association (IHSA) when involved in de-energizing isolated electrical circuits or apparatus.