Below you will find an overview of the content of the Practical Guideline "Hygienic Cabling in the Food Industry".
The National Practical Guideline "Hygienic Cabling in the Food Industry" deals with the hygienic aspects of:
- Field and machine cabling with the interconnection (from... till..., including transits)
- Including installation materials, cable trays, etcetera.
- Including personal safety (e.g. ATEX) and mounting/installing and completion
2 Normative references (legal requirements)
The EU regulations and EU directives constitute the law, EN standards are agreements made by the industry, which interpret the regulation and directives, wherever there is room left for interpretation. Practical standards are practical embodiments of EN standards and provide further guidance.
When drafting EN standards and practice standards, the hygienic aspects of cabling are not always taken into account, in particular, the cleanability is sometimes in conflict with the choices made. The working group has, where necessary, re-interpreted EU regulations and EU directives and substantiated deviations from EN standards and practice standards in such a way that it does not conflict with the thoughts the legislator had in drafting EU regulations and EU directives .
3 Terms and definitions
In order to get unambiguous description, the working group has drawn up a number of definitions that, in addition to the existing ones in the standards, are applied in the Hygienic Cabling Directive.
4 Risk analysis
The risk analysis discusses which dangerous situations can occur of (micro) biological, chemical or physical nature and to what extent they are real or not in certain areas.
5 Cleaning instructions
How is cleaning performed? The machine manufacturer must have included a cleaning instruction. That is to be done dry, controlled wet or wet. What are the consequences for cabling?
6 Design requirements
It is preferred to place the greater part of the cables in technical areas above, below or next to the production area. However, at a certain moment the cable will have to be led to a field object in the production area. The best way is perpendicularly from above or below to the field object.
There are different situations for wiring of cabinet to field object:
- Cabling in cable support systems along ceiling or walls.
- Cabling installed on machines or in tubes.
It is important that a plan for the routing of all cables is made. Only in this way can the right choices be made regarding materials, mounting, coding and connections.
The choice of materials for cable ducting and cables must match the local conditions, eg products and detergents. A gland is a critical point. Cable ties must be detectable, because of parts during application and wear. Prevent cable bundling, eg by a wireless system or using protective hoses (conduits).
In the end, cables are present, but how are they supported? A solid duct, with loose or fixed lid, or a wire duct or cable ladder? All shapes are discussed and attention is given to how cleanable each system is. The new cable support system is positive and, unlike the other systems, appears to be applicable in all areas.
Cables around machines can be guided in different ways: by rod, by rings, but there is also a new variant: clamped in springs. Existing systems to support multiple cables can also be improved by plastic blocks. Another good option is a protective hose (conduit).
Cable binders prove to be poorly cleanable in every application: avoid them as much as possible.
Cable coding can lead to problematic situations because attached objects, such as nameplates, can retain dirt and break off. Also labels can loosen.
All field components must be accessible for cleaning - possibly with tools. The connection of the field object is preferably from below via a gland connection. A gland connection on the side means a wrong load on the sealing ring and the gland. Objects that are sensitive to water cleaning must be protected and, as far as possible, not be placed in the field but in a hygienic cabinet.
Dirt must be visible on such cabinets, water must be able to drain and the seal, lock and hinges should not retain any dirt.
Cabling at valve clusters must be well planned so that cables can be combined as much as possible and do not get contaminated by unexpected leakage.
There are various solutions to guide cables from one room to another that are hermetically sealed to meet fire safety and hygiene requirements concerning pests.
7 Implementation & Verification
For applying hygienic cabling it is important to clean well during and after installation.
8 Working visits
Where did the working group go for discussion and inspiration?
Various appendices show how the new cabling system for field cabling can be applied horizontally, vertically and crosswise.