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Ontario Electrical Safety Code (OESC), 28th Edition - 2021
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The 28th edition of the Ontario Electrical Safety Code (OESC) includes the 25th edition of the Canadian Electrical Code, Part I, plus Ontario-specific amendments. The OESC is the law in Ontario for electrical installation. This new edition has been updated to enhance electrical safety and better protect electrical workers and the public.
Highlights and Key Changes:
• Provided requirements to support reduction in the potential for fires and the loss of animals in buildings housing livestock
• Provided clear electrical safety installation requirements for energy storage systems (ESS), harmonized with other codes and standards
• Introduced guidance for electrical installations in flood hazard zones and when electrical equipment has been exposed to water to mitigate the potential risks
• Requiring GFCI protection for all outdoor receptacles to mitigate the potential for electrical shock hazard
• Keeping workers safe by requiring additional receptacles for mobile structures connected to transfer equipment
• In Ontario, mitigating the potential for shock or electrocution when structures are erected in close proximity to customer-owned powerlines
• In Ontario, keeping reduced conductor sizes for services and feeders for dwelling units by following current installation practices
Why You Need the New Edition of the Ontario Electrical Safety Code
Compliance with the requirements of the latest edition of the OESC is the law for anyone performing electrical installations in the province of Ontario. The new OESC is based on the 25th edition of the Canadian Electrical Code, Part I, which is developed through the efforts of a number of volunteer technical committees and subcommittees representing key electrical industry stakeholders and jurisdictions across Canada.
Updated every three years in collaboration with safety partners, the 2021 OESC reflects changes in technologies and best practices and helps decrease the risk of injuries and costly re-works of electrical installation projects in Ontario.
Preface to the 28th edition of the Ontario Electrical Safety Code
This edition of the Ontario Electrical Safety Code contains the standards referenced by the Ontario Regulation made in 2021 pursuant to the Electricity Act regarding the Ontario Electrical Safety Code. Reference should always be made to the Regulation, and amendments thereto, as may be made from time to time.
This edition contains electrical safety requirements for wiring and equipment in buildings, structures, and premises, with the exception of mines, railways, aircraft, marine vessels, installations used for communication purposes, and automobiles.
As electrical hazards occur mainly because of overloading and abuse of wiring systems, it is recommended that initial installations be planned with adequate provision for possible future uses of electricity.
The 28th edition of the Ontario Electrical Safety Code consists of CSA C22.1:21, Canadian Electrical Code, Part I, and the Ontario Amendments to CSA C22.1:21, Canadian Electrical Code, Part I, dated November 2021.
Ontario Electrical Safety Code (OESC), 27th Edition - 2018
Ontario Electrical Safety Code ( OESC ), 26th edition - 2015
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