Danger of asphyxiation
Car exhaust fumes contain carbon monoxide (CO) - a colorless,
odorless gas. If inhaled, carbon monoxide causes an oxygen
deficiency in the body. Extreme caution is therefore essential
when working in a pit, as some of the components of the exhaust
gas are heavier than air and settle at the bottom of the pit.
Caution is also necessary when working on LPG-driven vehicles.
Safety precautions:
- Always ensure effective ventilation and suction (especially
when working in a pit).
- Always switch on and connect the suction plant in a closed
area.
Danger of injury
Danger of crushing
If the vehicle is not prevented from rolling away, there is a danger
of people being crushed against a workbench, for example. Both
running and stationary engines have rotating and moving parts
(e.g. belt drives) which may cause injuries to fingers and arms. A
special hazard is presented by electrically driven fans, in that they
may be switched on without warning while the engine is stationary
and the ignition is switched off.
Safety precautions:
- Take steps to prevent the vehicle from rolling away while it is
being tested.
Select the park position if the vehicle has an automatic transmis-
sion and apply the handbrake or lock the wheels with chocks
(wedges).
- Keep well away from rotating/moving parts while the engine is
running.
- When working on or in the vicinity of electrically driven fans,
allow the engine to cool down first, then disconnect the plug of
the fan motor.
- Keep the tester connecting cables well away from all rotating
parts.
Danger of burning
When working on a hot engine, there is a risk of injury from
burning if such components as the exhaust gas manifold, the
turbocharger, the Lambda sensor, etc. are touched or if parts of
the body come too close to them. These components may be
heated to temperatures of several hundred degrees Celsius.
Depending on the duration of the exhaust gas measurements, the
sampling probe of the exhaust gas measuring instrument may also
become extremely hot.
Safety precautions:
- Always wear protective clothing, e.g. gloves.
- Allow the engine to cool down first (this also applies to auxiliary
heating systems).
- Keep the tester connecting cables well away from all hot parts.
- Do not leave the engine running any longer than necessary for
the test or setting.
Noise
Noise levels in excess of 70 dB(A) can occur when measure-
ments are carried out on a vehicle, especially at high engine
speeds. Damage to hearing may result if human beings are
exposed to noise at such levels over an extended period of time.
Safety precautions:
- If necessary, noise protection facilities must be provided by the
owner at all workplaces in the vicinity of the testing area.
- If necessary, suitable personal noise protection facilities must
be used by the operator.
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