The HVAC industry in Canada is governed by the Technical and Safety Authority (TSSA) which is a not-for-profit corporation established by the Province of Ontario to administer the Technical Standards and Safety Act, 2000 (the Act) and its regulations. It's one of several administrative authorities that enforce Ontario’s consumer protection, public safety laws and investigate violations. The TSSA is Ontario’s public safety regulator for Elevating & Amusement Devices, Ski Lifts, Fuels, Boilers & Pressure Vessels and Operating Engineers.
The TSSA’s regulatory activities include rulemaking (primarily by adopting technical codes as law), certification of technicians, licensing of facilities, registration of businesses, auditing and inspection, investigating incidents and enforcement activities, as well as public education and awareness campaigns.
The Technical Standards and Safety Act, 2000, S.O. 2000, c. 16 is the specific act used to regulate the HVAC industry so it's important to be familiar with this legislation for certification, licensing and professional practice.
The HVAC industry also uses several other standards, codes and regulations in their practice. Please see the listing below for some of these to increase understanding of how they impact the industry. The two library databases which provide these codes and standards for HVAC include the CSA OnDemand and Techstreet. Check them out!
From: https://www.tssa.org/
Ontario electrical safety code : consisting of CSA C22.1:21 Canadian electrical code, Part I, Safety standard for electrical installations (Twenty-fifth edition) and Ontario amendments to CSA C22.1:21, Canadian electrical code, Part I. by 
Ontario Electrical Safety Code : electrical quick reference by 