Page 331 - IGC BOOK

Interlocking Guards

Interlocked guards work by cutting power to the
machine when the guard is opened. They are a good
guard to use when a machine needs to be accessed
often. An interlocked guard may use electrical.
mechanical, hydraulic, or pneumatic power or any
combination of these.

Interlocking guard which has a movable part so
connected with the machinery controls that:

• the parts of the machinery causing danger cannot
be set in motion until the guard is closed.

• the power is switched off and the motion braked before the guard can be opened sufficiently
to allow access to the dangerous parts.
• access to the danger point or area is denied while the danger exists.

Advantages Limitations

• connected to machine controls, hence • required careful adjustments and
machine does not operate when a guard maintenance.
remain open. • do not assume that they are reliable.
• easy for frequent access. • difficult to do inspection or testing.
• any failure or loss of power does not • gate system can be easily by-passed by
expose people to danger. stepping inside the gate.

Adjustable and Self-Adjusting Guards

Adjustable guards are made up of a fixed guard with
adjustable elements that are moved to suit each task.

They can be:

• self-adjusting – guards that are forced open by the entry
of work

• distance guards – barriers that can be moved to a safe
distance from the danger zone.

ENSIGN | Unit IG2 – Element 9 – Work 15
Equipment