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Stephanie: And it’s crucial that there's just a single key to each restricted area. The whole idea
of having a lock-out system is to ensure that only one person has access to switchgear at any
given time. So whatever happens, someone cannot switch on a circuit at a switchboard while
somebody else is working on it somewhere else in the plant.
Lin: Mm, if we imagine a technician needs to, let's say they're going to change a motor on one of
the lines, they get a permit to work, and obtain the key to the switchboard from the electrical
supervisor. Then they take the key, unlock the door to the switchboard, switch off the circuit-
breaker for the motor, to isolate it, then lock the door again.
Stephanie: That's right. Then, while they're working, it’s vital that they keep the key on them
continuously.

d Which of the following phrases give more emphasis than it’s important, and which give
less?
• it’s crucial 3 it’s preferable
• it’s essential 4 it’s vital

e Rewrite the following precautions using the phrases in the box to add emphasis.
at all times; every single; it's crucial; it's essential; it's vital; under
no circumstances;

1 The fire exit should always be kept clear.
The -five exit should. be kept clear at all times.
2 It’s important to test that the circuit is isolated.

3 You should reset the alarm routinely when you start the system.

4 It’s a good idea to check that the cable is not damaged.

5 It’s recommended that you should only store non-flammable materials in this zone.

6 Nobody should enter the restricted area without permission.

7 Before pressurising the system, make sure all the connections are tight.

f In pairs, discuss the following basic precautions for working on electrical circuits.
Before starting:
* Isolate circuit at switchboard
* Test circuit - no current
During work:
* Tighten connections fully
* Don’t damage insulation
To finish:
* Check no loose wires
* Test circuit
6a Read the following extract from an electricity company newsletter. What procedure
does the article describe?

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