“practice of professional engineering” means any act of planning, designing, composing, evaluating, advising, reporting, directing or supervising that requires the application of engineering principles and concerns the safeguarding of life, health, property, economic interests, the public welfare or the environment, or the managing of any such act; (“exercice de la profession d’ingénieur”)

No person shall engage in the practice of professional engineering or hold himself, herself or itself out as engaging in the practice of professional engineering unless the person is the holder of a licence, a temporary licence, a provisional licence or a limited licence. R.S.O. 1990, c. P.28, s. 12 (1); 2001, c. 9, Sched. B, s. 11 (16).

Ref: http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_90p28_e.htm

 (2)Ability to practice Engineering

In all provinces and territories, it is unlawful to practice Professional engineering and hold yourself as a Professional Engineer without a license to practice. However, some provinces provide exemptions allowing certified engineering technologists to practice under certain circumstances.