Safety Design: Scope of Guarding and Information Provided to the User

The guard provided with the machine is always limited in extent. The reasonable extent is near the envelope of the machine, and some path for package entry and exit is required. The manual and drawings should instruct the user on the customer’s obligation to provide integration guarding to complement the guard provided with the machine.

This is only reasonable as the infeed, outfeed, and reject path(s) are controlled by the customer. The fact that the user must provide integration guarding does not mean that the equipment is not eligible for a CE mark. The Machinery (Safety) Directive clearly identifies the responsibility of the user to consider safety measures for the production line as a whole.

Provide the most complete closure of the hazard area up to the normal envelope of the machine. Extensions of guards beyond the normal envelope must consider the interferences presented by the Customer’s other equipment, and be documented for each individual application.

We cannot control the Customer’s environment. We can only control the design and declare the design and hazards to the Customer, so they can determine the reasonable safety measures beyond our machine envelope.

Direction and Accepted Form:

Drawings provided to the user must declare:

The overall envelope of the system.
The areas for transfer of product onto and off of the inspection equipment.
The diameters or other transfer restrictions of the areas of transfer.
The limits of the guarding provided.
Identification of the area where customer integration-guarding begins.
Identification of all safety measures on the equipment.
Input power location, voltage, number of phases.
Pneumatics location, interface, maximum flow rate, pressure limits.
Access panels for maintenance and areas required for hinged doors, guard removal, etc.
Heights of the lowest cross-members or structures that affect cleaning under the machine.
Direction of product travel.
Direction of rejected packages.
Limitations created by apertures for guarding metal detectors.

Drawings that are specific to the application are best as they more precisely show the machine as constructed.

The drawing is a principal communication tool to declare the safety measures; it reinforces the message in the manual by graphical means.

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