PASMA Tower Assembly Methods 2 — Questions and Answers
Question 1: What is the correct sequence for dismantling a mobile tower scaffold?
- Bottom up, removing base frames first
- Top down, reversing the assembly procedure (Correct answer)
- Remove all platforms first, then frames
- Any order is acceptable as long as it is quick
Correct answer: Top down, reversing the assembly procedure
Towers must always be dismantled from the top down, reversing the assembly sequence. This maintains structural integrity throughout the process and ensures operatives are always working from a stable platform.
Question 2: What is the purpose of horizontal braces (ledgers) in a tower scaffold?
- To provide a place to hang tools
- To provide lateral stability and maintain frame spacing (Correct answer)
- To act as a ladder for climbing
- To support advertising banners
Correct answer: To provide lateral stability and maintain frame spacing
Horizontal braces connect the two frames together, maintaining the correct spacing and providing lateral stability. Without them, the tower would be prone to racking and collapse.
Question 3: What is the function of diagonal braces on a tower scaffold?
- They are decorative only
- They prevent racking (lateral sway) of the tower (Correct answer)
- They are used solely for climbing access
- They reduce the weight of the tower
Correct answer: They prevent racking (lateral sway) of the tower
Diagonal braces prevent racking, which is the tendency of the tower to sway or lean sideways. They triangulate the structure, converting it from a potentially unstable parallelogram into rigid triangles.
Question 4: When assembling a tower, at what height must a platform with edge protection first be provided?
- At any height where there is a risk of a fall (Correct answer)
- Only above 5 metres
- Only above 10 metres
- Only at the very top of the tower
Correct answer: At any height where there is a risk of a fall
Under the Work at Height Regulations 2005, there is no minimum height threshold — platforms and edge protection must be provided at any height where a person could fall and injure themselves. Even falls from low heights can cause serious injury.
Question 5: What type of locking mechanism is typically used to secure frames together during assembly?
- Rope ties
- Spring-loaded gravity locks or wind locks (Correct answer)
- Adhesive tape
- Welding
Correct answer: Spring-loaded gravity locks or wind locks
Modern tower scaffolds use spring-loaded gravity locks (also called wind locks or spigot clips) that automatically engage when frames are connected. These must be checked to ensure they have fully locked into position.
Question 6: What should be done if a component is found to be damaged during assembly?
- Repair it on site with tape and continue
- Remove it from use, label it as defective, and replace with a sound component (Correct answer)
- Use it but inform the supervisor later
- Leave it in place but add an extra brace nearby
Correct answer: Remove it from use, label it as defective, and replace with a sound component
Damaged components must be immediately removed from use and clearly marked or tagged as defective to prevent them being used again. Only sound components that meet the manufacturer's specification should be used in the tower.
PASMA Tower Assembly Methods 2
What is the correct sequence for dismantling a mobile tower scaffold?