Lather / Interior Systems Mechanic (Red Seal)

Performs common occupational skills

How far above an upper landing must a straight ladder extend when it is used to access an elevated work platform?

1. At least one metre, about three rungs, above the landing or upper support point
2. Level with the landing surface, so the ladder does not obstruct the platform edge
3. Exactly half a metre above the landing in every situation, regardless of platform
4. As far as the ladder happens to reach, since there is no minimum extension rule

A straight ladder used for access must extend at least one metre, about three rungs, above the landing so the worker has a secure handhold while stepping on and off. Stopping level with the landing leaves nothing to grip during the transition, which is when most ladder falls happen. A fixed half-metre is below the required handhold height, so it does not give a safe grip. Leaving it to whatever the ladder reaches ignores the minimum-extension rule that controls the detail. Extending at least one metre above the landing is the correct access setup.

RSOS 2021 | A-2.07 Uses scaffolding and access equipment

Performs framing activities

What best describes a spanned ceiling in steel framing?

1. A ceiling hung on adjustable wire hangers dropped from the structural deck above it
2. A ceiling formed only of lay-in acoustic tile resting in a suspended metal tee grid
3. A ceiling whose framing members span directly between supporting walls or beams
4. A ceiling sprayed in place as fireproofing directly against the underside of the slab

A spanned ceiling is framed so its members run directly between supporting walls or beams, carrying the ceiling across the room without intermediate hanger wires. A ceiling hung on wires is a suspended system, which is a different category from a spanned one. A tile-in-grid ceiling is a suspended acoustical system rather than a framed spanned ceiling. A sprayed underside is a surface coating, not a framed ceiling at all. Members spanning directly between supports is what defines a spanned ceiling.

RSOS 2021 | B-6.02 Frames spanned ceilings

Installs interior systems

An access panel must be installed in a one-hour fire-rated shaft wall to reach a valve. What type of panel is required?

1. Any plain hinged steel door panel, since all it has to do is cover over the opening in the wall
2. An open framed hole left with a loose board dropped in front of it for quick easy hand access
3. A fire-rated access panel that matches the required rating of the wall assembly
4. A light plastic panel picked mainly because its smooth face is the easiest one to wipe down clean

A penetration in a fire-rated wall must be closed with a fire-rated access panel that matches the wall's required rating, or the fire separation is broken at that point. A standard non-rated metal panel defeats the rated separation even though it covers the opening. An open hole with a loose board provides no rated closure at all. A plastic panel offers no fire resistance and would fail in a fire. A fire-rated access panel matching the wall rating is what is required.

RSOS 2021 | C-8.06 Installs access panels