# What certification does the trade actually require?

## Ontario's largest trades by apprentices in training

- [Automotive Service Technician (310S) certification requirements](https://ontariocertificationregistry.ca/trades/310s-automotive-service-technician/)
- [Electrician - Construction and Maintenance (309A) certification requirements](https://ontariocertificationregistry.ca/trades/309a-electrician-construction-and-maintenance/)
- [Hairstylist (332A) certification requirements](https://ontariocertificationregistry.ca/trades/332a-hairstylist/)
- [General Carpenter (403A) certification requirements](https://ontariocertificationregistry.ca/trades/403a-general-carpenter/)
- [Child Development Practitioner (620C) certification requirements](https://ontariocertificationregistry.ca/trades/620c-child-development-practitioner/)
- [Cook (415A) certification requirements](https://ontariocertificationregistry.ca/trades/415a-cook/)
- [Truck and Coach Technician (310T) certification requirements](https://ontariocertificationregistry.ca/trades/310t-truck-and-coach-technician/)
- [Industrial Mechanic Millwright (433A) certification requirements](https://ontariocertificationregistry.ca/trades/433a-industrial-mechanic-millwright/)
- [Plumber (306A) certification requirements](https://ontariocertificationregistry.ca/trades/306a-plumber/)
- [Industrial Electrician (442A) certification requirements](https://ontariocertificationregistry.ca/trades/442a-industrial-electrician/)
- [Construction Craft Worker (450A) certification requirements](https://ontariocertificationregistry.ca/trades/450a-construction-craft-worker/)
- [General Machinist (429A) certification requirements](https://ontariocertificationregistry.ca/trades/429a-general-machinist/)

## Studying for a certifying exam?

We publish practice exam guides built to each trade's [published Red Seal exam breakdown](https://ontariocertificationregistry.ca/practice-exams/): the real question count, the real split across Major Work Activities, and the real mix of recall, application and problem-solving questions. Free sample questions with answers are on every product page.

![Construction Electrician (309A) Practice Exam cover](https://ontariocertificationregistry.ca/exam-covers/309a-electrician-construction-and-maintenance-768.png)

### [Construction Electrician (309A) Practice Exam](https://ontariocertificationregistry.ca/practice-exams/309a-electrician-construction-and-maintenance/)

$40 CAD

Free samples inside →

![Industrial Mechanic Millwright (433A) Practice Exam cover](https://ontariocertificationregistry.ca/exam-covers/433a-industrial-mechanic-millwright-768.png)

### [Industrial Mechanic Millwright (433A) Practice Exam](https://ontariocertificationregistry.ca/practice-exams/433a-industrial-mechanic-millwright/)

$40 CAD

Free samples inside →

[See every practice exam we publish](https://ontariocertificationregistry.ca/practice-exams/)

## How this registry works

Each record answers the questions people actually ask: is the trade compulsory, is there an exam, is there a ratio, is it Red Seal, and how do you get certified. Facts we have not yet verified against a primary source are marked as not published rather than estimated, and every page carries a visible last verified date. Read more about the method on the [about page](https://ontariocertificationregistry.ca/about/).

## Official verification sources

- Trades[O. Reg. 876/21, Prescribed Trades and Related Matters (e-Laws)](https://www.ontario.ca/laws/regulation/210876)
- Fuel certificates[O. Reg. 215/01, Fuel Industry Certificates (e-Laws)](https://www.ontario.ca/laws/regulation/010215)
- Refrigerants[O. Reg. 463/10, Ozone Depleting Substances and Other Halocarbons (e-Laws)](https://www.ontario.ca/laws/regulation/100463)
- Participation data[Ontario open data: Apprenticeships dataset](https://data.ontario.ca/dataset/apprenticeships)

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Source: https://ontariocertificationregistry.ca/