"Challenging" the 313A exam means writing the certificate of qualification exam without having completed an Ontario apprenticeship. You do not simply book the exam: Skilled Trades Ontario first decides, through a Trade Equivalency Assessment, whether your experience qualifies you to write it.
Who is the Trade Equivalency Assessment for?
According to Skilled Trades Ontario, it may suit you if your trade experience comes from outside Canada, from another Canadian province or territory where you do not hold a Certificate of Qualification or equivalent, or from the Canadian Forces. It is only available in trades that have a certifying exam, which includes 313A.
What do you have to prove?
Applicants are held to the same on-the-job standard as an Ontario apprentice. You must give sufficient, verifiable evidence of two things:
- Competency in the trade's skills, as defined by the trade's training standard.
- Experience at least equal to the prescribed or recommended total training time for the apprenticeship, counting both on-the-job and in-school hours. For 313A that apprenticeship is set at 9,000 hours.
How much does it cost, and what happens next?
The assessment costs $235 plus HST. If you are approved, you can challenge the certifying exam; if you pass, you pay a fee to be issued the Certificate of Qualification. If you are not approved, you can apply for a reassessment once you have additional evidence. Check the current application guide on the Skilled Trades Ontario site before applying.
How should an experienced mechanic prepare?
Experience is exactly what makes challengers overconfident in the wrong places. Someone with years of service work can be strong in maintenance and troubleshooting (25% of the exam) and still lose marks in planning installs, retrofits and commissioning documentation. Start by finding out which areas those are: the free five-question test takes three minutes, and the full diagnostic reports every work area. The 90-day study plan covers the rest.
Sources
- Skilled Trades Ontario: Trade Equivalency AssessmentEligibility, evidence, $235 + HST fee, reassessment; read 2026-09-21
- Skilled Trades Ontario: Refrigeration and Air Conditioning Systems Mechanic (313A)
Examen Studio is independent and not affiliated with the Red Seal Program or Skilled Trades Ontario. This article is a study aid; on the job, follow current codes, regulations and manufacturer instructions.