Indirect productcontactzoneareas willbe consideredas product contact
zoneareas:
∑ The equipmentshall be installed suchthat it will not causecontamination of
the ingredients,raw foodsand end-products.
∑ Separationbetween product contact and non-product contactareasprevents
cross-contaminationduringoperations.Indirect productcontactzoneareas
must be designedas if theywereproductcontact zoneareas.
∑ Product contactsurfacesare designedto prevent build-up of product residue
during operations.
∑ Separationbetween product contactareasand non-productcontactareashas
to be determined by a risk analysis.
∑ All the partsof the equipment shouldbe installedat a distanceof 1 m from
walls, ceilingsand adjacent equipment to allow: transport systems for
ingredientsand packagingmaterial and for easyaccess of operatingstaff(for
inspection,cleaningand disinfecting,maintenance and to solve breakdowns).
∑ Surfaces withdirect and indirect productcontactare cleanableas measured
by <1 colony-forming unit (cfu)per 25 cm^2 , <1 cfu per 10 ml whenthe item
is rinsed, acceptable RLU (reflected light unit) (device specific) when
measuredby residual ATP(adenosine triphosphate), and/or negative for
residual proteinor carbohydratewhenusing swabsto detect residual protein
or carbohydrate (measured post-installation).
Special attention must be paidto the followingaspects:
∑ Packing machine materials: see ISO 14159, chapter 5: Materials of construction'. ∑ Product contactsurfaces and coatings: surfacesof the machine partsthat come in directcontactwithhigh-risk ingredientsmust be madefromnon- toxicmaterials and must havefinishes that are impervious, non-absorbing, washable,smoothand crack-free to resistmicrobialsettlement and that can be easily cleanedand disinfected.(Note: surface defects on machined componentsare not acceptable.) For detailedinformation:see ISO14159, chapter 7.1:Surfaces and geometry'and chapter7.2: `Surfacefinish/surface
roughness'.
Conveyorswithproduct contact
Conveyorbeltsmust be made fromnon-toxic materials and musthavefinishes
that are impervious,non-absorbing,washable,smoothand crack-free so they
resistmicrobialsettlement and mayeasily be cleanedand disinfected.The
surface finishmust be suchthat formationof bio-filmsunderthe conditionsof
solidfoodpackingprocesscannotoccuror is limited to a minimumwherebythe
films can be cleaned.
All beltingmustbe easilyremovable or the belt tension mustbe easyto
remove withouttoolsso the surfaces underneath can be cleaned.Belt tensionis
adequate throughoutoperationsto preventwaterpooling on belts.
236 Handbookof hygiene controlin the foodindustry