Steamfitter / Pipefitter (307A) — Red Seal

Performs common occupational skills

What governs who may weld pressure piping and the procedure they follow on a Canadian steam system?

1. Any journeyperson welder may proceed once the foreman has visually approved the first completed joint
2. A qualified welding procedure is only mandatory once the system operates above 150 psi design pressure
3. All welding must be done using a qualified procedure, and welders must be qualified by testing
4. Procedure qualification governs shop fabrication welds, while field welds rely on the welder's stamp alone

Pressure-piping welding is controlled work: it must follow a qualified welding procedure specification, and each welder must pass a qualification test for the process and position used. Foreman approval does not substitute for documented qualification. The requirement applies across pressure systems, not only those above an arbitrary pressure, and it covers both shop and field welds because a field joint carries the same pressure as a shop joint.

RSOS 2022 | A-2.03 Uses welding equipment

Performs layout, fabrication and piping installation

A 30 m carbon steel steam main will see roughly a 55°C temperature rise from cold to operating. Approximately how much will it grow, and why does this matter for layout?

1. About 5 mm, which a few extra pipe hangers along the run will easily absorb
2. About 20 mm (3/4 in.) — enough that expansion provisions must be designed in
3. About 200 mm, so the steam main cannot be run rigidly and must be all hose
4. About 1 mm per metre, regardless of the temperature rise that the steam puts on it

Carbon steel grows roughly 20 mm (3/4 in.) per 30 m for about a 55°C rise, which is far more than a rigid run can absorb without overstressing joints and supports. That is why loops, offsets, or joints are designed into the layout. A 2 mm estimate badly understates the movement, and 100 mm overstates it for this length and rise. Steel clearly does expand, so ignoring it leads to leaks and damaged supports.

RSOS 2022 | B-6.03 Lays out and installs carbon steel piping, fittings and related components

Performs rigging, hoisting, lifting and positioning

Why must the area beneath and around a suspended pipe load be kept clear during a lift?

1. To protect workers from injury if the load shifts, swings, or drops
2. To reserve a clear spot for the crane operator to park the rig
3. To stop airborne dust from settling onto the rigging slings
4. To keep the lift area looking tidy and organized for any inspectors visiting the site

An exclusion zone keeps people out from under and beside a suspended load so that if it shifts, swings, or falls, no one is struck. It is a personnel-protection measure, not a parking provision. Sling cleanliness has nothing to do with clearing the area. Appearance to inspectors is irrelevant — the zone exists because a suspended load is a serious struck-by hazard until it is safely landed.

RSOS 2022 | C-9.05 Secures lift area