9.4 Control measures for machinery

Written by Imran Qureshi (NEBOSH)

NEBOSH IGC · Workplace hazards · 15 questions

Name: ____________________ Date: ____________

An interlocking guard:
- A Is never opened
- B Stops the machine if opened
- C Is fixed with tools only
- D Is only decorative
A hold-to-run control:
- A Is the same as a fixed guard
- B Runs the machine for an hour
- C Works only while the control is held
- D Is an emergency stop
Which is a basic requirement of a guard?
- A It must be removed for maintenance
- B It should increase risk
- C It should restrict the view
- D It should not be easily bypassed
A fixed guard is:
- A Easily opened by hand during use
- B Always interlocked
- C Self-adjusting
- D Kept in place by tools or fasteners
An adjustable guard is:
- A Adjusted to suit the task
- B Never moved
- C A type of PPE
- D Only in offices
The first choice among machine guards is generally a:
- A Training session
- B Fixed guard
- C Warning sign
- D PPE
A two-hand control:
- A Needs only one hand
- B Is a type of PPE
- C Keeps the machine running without hands
- D Requires the operator's hands to be clear of the danger area to start the machine
A light curtain is an example of:
- A A trip device that stops the machine when the beam is broken
- B A fixed guard
- C PPE
- D A jig
A push-stick is used to:
- A Keep hands away from a cutting tool
- B Increase noise
- C Lift people
- D Increase vibration
A limitation of guards is that they:
- A Can be bypassed
- B Never wear out
- C Cannot be maintained
- D Always remove all risk
A limitation of PPE as a machine control is that it:
- A Removes the hazard
- B Is always strong enough
- C Never fails
- D Depends on the user
A guard must:
- A Allow maintenance without being removed where possible
- B Increase risk
- C Be easily bypassed
- D Block the operator's view
An emergency stop control:
- A Stops the machine quickly when a danger arises
- B Starts the machine
- C Increases speed
- D Replaces guards
A hold-to-run control means that the machine:
- A Runs until switched off
- B Runs only while the control is held
- C Runs without a control
- D Never stops
Why should a guard not restrict the operator's view?
- A To reduce light
- B To increase noise
- C To raise the temperature
- D The operator needs to see the work to control it safely

Answer key

1. B, 2. C, 3. D, 4. D, 5. A, 6. B, 7. D, 8. A, 9. A, 10. A, 11. D, 12. A, 13. A, 14. B, 15. D

The machine cannot run unless the guard is closed.
It stops when released.
Guards must be hard to bypass.
It cannot be removed without a tool.
Self-adjusting guards move with the material.
The order is fixed guard, interlocking guard, devices, then information and PPE.
It keeps hands away during the cycle.
Sensitive protective equipment includes light curtains and pressure mats.
Jigs, holders and push-sticks are other methods.
Interlocks must not be easily defeated.
It is a last resort.
A guard should be compatible with the process.
It is a protective device.
It prevents hands being in danger at the same time.
A guard that blocks the view encourages bypassing.