The electrical safety develops with the technical progress. In 1989 OSHA[1] promulgated a much-needed regulation in the General Industry Regulations. Several standards are defined for control of hazardous energy, or lockout/tagout. In 1995 OSHA was successful in promulgation of regulations for utility.[2]
In 1994 were established Electrical Safety Foundation International non-profit organization dedicated exclusively to promoting electrical safety at home and in the workplace.[3]
Standard 29 CFR 1910.269 – for electric power generation, transmission, and distribution, contained comprehensive regulations and addressed control of hazardous energy sources for power plant locations
Lightning and Earthing protection systems are essential for the protection of humans, structures, protecting buildings from mechanical destruction caused by lightning effects and the associated risk of fire, Transmission lines, and electrical equipment from electric shock and Overcurrent.[6]
lightning rod (simple rod or with triggering system)
lightning rod with taut wires.
lightning conductor with meshed cage (Faraday cage)
Physiological effects of electricity
Electrical shocks on humans can lead to permanent disabilities or death. Size, frequency and duration of the electrical current affect the damage.[8] The effects from electric shock can be: stopping the heart beating properly, preventing the person from breathing, causing muscle spasms. The skin features also affect the consequences of electric shock.[9]
Electric shock graph
Indirect contact – can be avoided by automatic disconnection for TT system, automatic disconnection for TN systems, automatic disconnection on a second fault in an IT system, measures of protection against direct or indirect contact without automatic disconnection of supply
Direct contact – can be avoided by protection by the insulation of live parts, protection by means of barriers or enclosures, partial measures of protection, particular measures of protection[10]
Electrical safety conductors
United States(USA) NEC 2008 Table 250.122 – Safeco Electric Supply
Electrical safety standards
Australia(AUS) Australian Standards – Australia – AS/NZS 3000:2007, AS/NZS 3012:2010, AS/NZS 3017:2007, AS/NZS 3760:2010, AS/NZS 4836:2011[11]
Bulgaria(BUL) Български Държавен Стандарт – (On English:Bulgarian state standard) – БДС 12.2.096:1986 Bulgaria[12]
Дулицкий Г. А., Комаревцев А. П. Электробезопасность при эксплуатации электроустановок напряжением до 1000 В. Справочник. — М.: Воениздат, 1988.
IEC 60050-195:1998. International Electrotechnical Vocabulary. Part 195: Earthing and protection against electric shock. Edition 1.0. – Geneva: IEC, 1998‑08.
