illumination. For such installations, due consideration should be given to
equipment layout, uniformity of lightdistribution and the propercoordinationof
the luminaireswiththe ceilingconfiguration.
Luminaires should be supported by screwedrod fixed to the building
structureso as to avoidthe weightof the luminairebeingborneby the ceiling
(unlessthe ceilingis of the load-bearing/walk-ontype). Finalconnectionsfrom
the fixedwiringto the luminaireshould be via a 3-pin plugand socket (mounted
adjacent to the luminaire) and heat-resisting 3-core flexible cable. Ideally,
maintenance of the luminaire (e.g. the replacement of lamps) should be
undertakenfromwithinthe above-ceiling service area.
15.6 General requirementsfor construction materials
Materials usedfor the construction of hygienicproduction equipment should
meetcertainspecificrequirements.Contact materialsshould, underall operating
conditions, be inertto the productas wellas to the detergents and chemicals
usedto free equipment frommicroorganisms.Furthermore, theyshouldbe non-
toxicand comply with relevant local legislation (e.g.the Food and Drug
Administration). All materials (non-contactand contact)shouldbe:
∑ corrosion resistant;
∑ mechanicallystable;
∑ smoothlyfinished;
∑ easyto clean;
∑ suchthat the original surfacefinishis unaffectedunderall conditionsof use.
Fig. 15.6 Electricalequipmentand valvesbelowthe machinein a visualand cleanable
compartment100 mm fromthe floor.
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