Working at Heights: Guardrails, coverings and barriers

All 16 questions in this test

Every question and its answer choices. The correct answers and explanations appear when you take the test above.

1. When may a guardrail around an opening be removed temporarily?

   1. At the end of each shift so the area can be cleaned
   2. Whenever it gets in the way of carrying long materials
   3. Only after the building inspector has signed off the job
   4. To work at the opening, with workers protected and signs up

2. Posts of a guardrail are normally no more than how far apart, unless the system is built for greater loads?

   1. 1 metre only
   2. 10 metres
   3. 5 metres
   4. 2.4 metres

3. On a built-up roof being constructed or resurfaced, where must a barrier be placed?

   1. Right at the roof edge, touching the parapet wall
   2. Nowhere; barriers are not used on roofs
   3. In the work area, at least 2 m from the roof perimeter
   4. At ground level around the building's base

4. Which is acceptable to protect workers from an opening in a floor?

   1. A sheet of cardboard placed loosely on top of the hole for now
   2. A secured, identified cover able to support at least 2.4 kN/m²
   3. A note in the site office saying the hole exists
   4. A traffic cone set beside the opening during the day

5. What is the minimum size of the posts and rails of a wooden guardrail?

   1. 19 mm by 38 mm
   2. 38 mm by 89 mm
   3. 10 mm round
   4. 89 mm by 140 mm

6. At the perimeter of a work surface, how far may the guardrail be from the edge?

   1. No more than 1 metre from it
   2. No more than 300 millimetres
   3. At least 2 metres
   4. Exactly 600 millimetres

7. Where must the intermediate rail be located?

   1. Midway between the top rail and the toe board
   2. Right on top of the toe board at floor level only
   3. Anywhere the installer finds convenient
   4. Above the top rail as an extra hand grip

8. Which material may replace the intermediate rail of a guardrail?

   1. A painted line on the floor near the edge
   2. A row of traffic cones along the edge
   3. A single strand of plastic flagging tape
   4. Material that can withstand a 450 N point load

9. What is the minimum diameter of wire rope used for a guardrail's top and intermediate rails?

   1. 10 millimetres
   2. 5 millimetres
   3. 25 millimetres
   4. 3 millimetres

10. What should workers know before installing, relocating or removing guardrails?

    1. Nothing special; guardrail work is always risk-free at any height
    2. The precautions needed, since they may be exposed while doing it
    3. Only the brand name of the guardrail system being used
    4. Only how to paint the rails a highly visible colour

11. Which is a limitation of bump lines and barriers set back from an edge?

    1. They replace the need for any training or supervision
    2. They warn or limit access but cannot stop a falling worker
    3. They are stronger than guardrails in every situation
    4. They prevent all falls even at the very edge itself

12. How high must the top of a guardrail be above the surface?

    1. At least 1.5 m and not more than 2 m
    2. Any height, as long as it is painted
    3. At least 0.5 m and not more than 0.7 m
    4. At least 0.9 m and not more than 1.1 m

13. What lateral point load must the top rail of a guardrail resist?

    1. 675 newtons
    2. 100 newtons
    3. 225 newtons
    4. 2,000 newtons

14. What is the minimum height of a guardrail toe board?

    1. 1 metre
    2. 300 millimetres
    3. 25 millimetres
    4. 89 millimetres

15. What three parts must a guardrail system have?

    1. A handrail, a kick plate and a mesh roof
    2. Two posts, a chain and a hanging warning sign
    3. A top rail, a warning flag and a rope barrier
    4. A top rail, an intermediate rail and a toe board

16. Which wood is required for a wooden guardrail?

    1. Painted plywood offcuts of any grade
    2. Hardwood flooring left over from the job
    3. Construction-grade spruce, pine or fir
    4. Any scrap wood found on the site