Page 332 - IGC BOOK

Guards that move out of the way for each operation (automatic
guards) need special care. Hazards can be created between the
guard and:

• machine.
• person.

• work piece.

Staff need full training on using and adjusting these guards. These
guards are only effective when the people use them correctly.

Advantages Limitations

• dangerous parts are covered • protection may not be possible at all
• adjustable guards allow operator to times
adjust manually. • requires frequent maintenance and/or
adjustments
• may interfere visibility

Sensitive Protective Equipment (Trip Devices)

It is designed to cut the power if someone
reached into a dangerous part of a machine. If the
system fails, there is no physical barrier to prevent
people coming into contact with dangerous parts.
Sensor are used to identify the presence of
someone who tries to reach the dangerous parts,
hence, it reduces the severity.

There are different types of sensitive protective
devices:

Trip Guards

Commonly include a trip bar attached to the machines close to the dangerous parts, when
touched causes the machines to stop with the assistance of braking devices.

Photoelectric Devices

Photoelectric safety devices use light beams that stop machines working when the light beam is
broken. This method is often used when fixed or interlocked mechanical guards are not

practical.

ENSIGN | Unit IG2 – Element 9 – Work 16
Equipment