3.3 The Hierarchy in Practice

You manage a utility company's repair team. A water pipe has burst under a busy road, and the job will take about two days. You must decide how to protect your workers from traffic, and you start at the top of the hierarchy.

1. Eliminate the hazard. Close the road and divert the traffic. Is that practical for a two day job?
2. Reduce the hazard. Work at night, when there is less traffic. Would that be possible, and would it help?
3. Keep people away. If neither is practical, close one lane, set a speed limit and put up a physical barrier between the traffic and the crew.
4. Safe system of work. Write down how the work will be done on site and how the crew must behave.
5. PPE. Provide reflective jackets, hard hats, gloves and ear defenders where they are needed.

You will have several demands to balance when you choose:

• How many people need protection? A noisy machine in a sound proof enclosure may be better than buying hearing protection for everyone.
• How much does the control rely on human behaviour?
• How often will it need to be tested, maintained and replaced?
• How much does it cost, and how much will it reduce the risk? Could it create a new risk?

The final decision is usually a compromise between these points.

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