You require 36 months of qualifying service for 4th Class, Motor or Steam, 6 months of which must be as Engineer or Engine Room Rating on one or more vessels the main engines of which must have a total power of at least 500 Kw (670.25 bhp).
You may note that it says "the MAIN ENGINES of which must have a TOTAL POWER of 500 Kw." It does NOT say "propulsive power" as it does for the higher 3rd, 2nd and 1st Class Certificates. The "main engines" need not be propulsion prime movers for 4th Class.
The remainder of the qualifying service may be in any combination of the experience listed in section 147 (1) table item 2 of the Marine Personnel Regulations, posted by Martin, http://laws-lois.justice.gc.ca/eng/regu ... .html#h-42
Other requirements are set out in the table at sect 147(1):
3. Certificates and other documents to be provided to the examiner
(a) MED with respect to STCW basic safety; STCW VI/1
(b) MED training with respect to proficiency in survival craft and rescue boats other than fast rescue boats; STCW VI/2
(c) MED in advanced fire fighting; STCW VI/3
(d) marine advanced first aid; (MAFA)
(e) ship watchkeeping practices taught using a propulsive plant simulator; (PPS 1) and
(f) for the sole purpose of obtaining a certificate with an STCW endorsement,
(i) practical skills for marine engineers, and
(ii) approved training record book for applicants for a Fourth-class Engineer certificate completed under the supervision of the vessel’s chief engineer.
4. Pass examinations
(a) An examination on ship watchkeeping practices using a propulsive plant simulator, after providing the certificate referred to in paragraph 3(e);
(b) after meeting the requirements of items 2 and 3 and paragraph (a), a written examination on general engineering knowledge at the fourth-class level;
(c) one of the following written examinations at the fourth-class level, after meeting the requirements of paragraph (b):
(i) in the case of an applicant for a Fourth-class Engineer, Motor Ship certificate, engineering knowledge of motor vessels, or
(ii) in the case of an applicant for a Fourth-class Engineer, Steamship certificate, engineering knowledge of steamships; and
(d) oral examination on the knowledge set out in paragraphs (a) to (c) and knowledge of the legislation relevant to the certificate sought, after passing the examination referred to in paragraph (c).
The kind of sea service is important and must consist of the activities set out in 147 (2) as far as possible. Obviously, a motor tug doesn't have a boiler or a rainmaker, for example:
(2) The qualifying service set out in paragraph 2(a) of the table to subsection (1) shall include the following duties:
(a) preparing main machinery and auxiliary equipment for sea;
(b) shutting down main machinery;
(c) operating main machinery;
(d) preparing, starting, coupling and changing over alternators and generators;
(e) transferring fuel;
(f) preparing and operating evaporators and distillation plants;
(g) operating oily water separators and conducting appropriate tests to ensure the correct operation of those separators;
(h) preparing and operating air compressors;
(i) preparing and starting steering gear and conducting appropriate tests to ensure the correct operation of the steering gear;
(j) testing boiler water-level gauges under normal working conditions;
(k) operating boilers, including the combustion system;
(l) transferring ballast and fresh water;
(m) lubricating machinery;
(n) pumping bilges;
(o) taking machinery readings and compiling the data in the engine-room log books; and
(p) acting as assistant to the engineer in charge of the engineering watch.
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