As a starting point consult the New Brunswick Regulation 84-174 & the Boiler and Pressure Vessel Act for useful information on pressure equipment exemptions and requirements, pressure vessel engineering. Always consult the chief inspector of a jurisdiction.
New Brunswick Canadian Registration Numbers fitting registrations are issued by ACI Central who is the designated regulatory authority for seven provinces and territories that include: Newfoundland, Nunavut, Prince Edward Island, New Brunswick, Nova Scotia, North West Territories, Yukon. This small agency located on Prince Edward Island vastly simplifies what could be a terribly long and bureaucratic process of dealing with seven entities.
For boilers, pressure vessels and piping system design registration applications you may also contact the Justice and Public Safety site for the Government of New Brunswick provides additional information and useful contacts.