PASMA Tower Assembly Methods 4 — Questions and Answers
Question 1: What is the correct internal access method for climbing a tower scaffold?
- An external ladder leaning against the tower
- Climbing the diagonal braces on the outside
- Using the built-in internal ladder frames via the trapdoor hatch (Correct answer)
- Scaling the outside frames hand over hand
Correct answer: Using the built-in internal ladder frames via the trapdoor hatch
Internal ladder frames with trapdoor platforms provide the safest means of access. External climbing or external ladders can destabilise the tower and expose the operative to a greater fall risk.
Question 2: What should be done with the trapdoor hatch after climbing through it?
- Leave it open for ventilation
- Close it to create a full working platform (Correct answer)
- Remove it and store it on the ground
- Prop it open with a brick
Correct answer: Close it to create a full working platform
The trapdoor must be closed after climbing through to create a complete working platform. An open trapdoor creates a trip hazard and a fall risk, and reduces the effective platform area.
Question 3: What is the minimum platform width recommended by PASMA for a working platform?
- 400mm
- 600mm (Correct answer)
- 900mm
- 1200mm
Correct answer: 600mm
The minimum recommended platform width is 600mm (approximately 2 feet). Narrower platforms do not provide adequate space for safe working and increase the risk of overbalancing.
Question 4: When building a tower adjacent to a building, what must be considered regarding the height-to-base ratio?
- The ratio can be ignored because the building provides support
- The ratio must still be maintained unless the tower is tied to the structure (Correct answer)
- The building automatically acts as an outrigger
- Adjacent buildings always reduce the required ratio by half
Correct answer: The ratio must still be maintained unless the tower is tied to the structure
The height-to-base ratio must always be maintained unless the tower is properly tied into the adjacent structure using appropriate fixings. Simply being near a building does not provide stability.
Question 5: What is the purpose of the adjustable leg (or screw jack) on a tower scaffold?
- To increase the height of the tower beyond its design limit
- To allow levelling of the tower on uneven ground (Correct answer)
- To anchor the tower permanently into the ground
- To replace damaged castors
Correct answer: To allow levelling of the tower on uneven ground
Adjustable legs or screw jacks allow the tower to be levelled on slightly uneven ground. They must not be extended beyond the manufacturer's recommended limit, and a spirit level should be used to check the tower is plumb and level.
Question 6: How should components be passed up to the operative assembling the tower?
- Thrown up to save time
- Passed by hand from the interior of the tower or hoisted using a gin wheel (Correct answer)
- Launched upwards using a catapult
- Tied to a drone and flown up
Correct answer: Passed by hand from the interior of the tower or hoisted using a gin wheel
Components should be passed by hand internally or lifted using a gin wheel or line. Throwing components risks dropping them on people below and can unbalance the operative catching them.
PASMA Tower Assembly Methods 4
What is the correct internal access method for climbing a tower scaffold?