the area.The washarea shouldconsistof a holdingarea for equipment,etc.,
awaiting cleaning, a cleaningareafor manual or automaticcleaning (e.g.
traywash)as appropriate, and a holding/dryingarea where equipment can be
storedprior to use. These areasshouldbe as segregatedas possible.
∑ All cleaning equipment, includinghandtools(brushes,squeegees,shovels,
etc.)and largerequipment (pressure washers,floorscrubbers and automats,
etc.)shouldremainin highrisk and be colour codedto differentiatebetween
high-and low-riskequipmentif necessary.Special provision should be made
for the storageof suchequipment whennot in use.
∑ Cleaningchemicals should preferablybe pipedinto highrisk via a ring main
(whichshould be separatefromthe low-risk ring main). If this is not possible,
cleaning chemicals shouldbe storedin a purpose-built area.
∑ The most commonlyusedequipmentserviceitemsand spares, etc., together
withthe necessary handtoolsto undertakethe service,shouldbe storedin
highrisk.For certain operations,e.g. bladesharpening for meat slicers,
specificengineering roomsmayneedto be constructed.
∑ Provision should be made in highrisk for the storage of utensilsthat are used
on an irregularbasisbut that are too large to passthroughthe low/high-risk
barrier,e.g. stepladdersfor changingthe air distribution socks.
8.5 Barrier4: Finishedproduct enclosure
Thefourth barrier is productenclosure and has the objectiveof excluding
contamination,particularlyfrommicroorganisms,froma commerciallysterile
product. The fourthbarrierapproachis essential for the production of aseptic
foods, but is alsobeing usedfor the production of somechilled, ready-to-eat
foods. Product enclosurecan be undertakenby physicalsegregation(a box within
a box withina box)or by the use of highlyfiltered,directional air currents.
Withrespectto physicalsegregation, `gloveboxes'offerthe potentialto fully
encloseproduct withthe abilityto operate to asepticconditions.Gloveboxesfor
the food industry work in the same wayas gloveboxes for the medical,
microbiologicalor pharmaceuticalindustry, in whichthe foodis enclosedin a
sealedspace,totallyprotectedfromthe outsideenvironment, and manipulated
throughglovessealedinto an inspectionwindow.Theyworkbest if the product
is deliveredto themin a pasteurisedcondition,is packedwithinthe box and
involves little manual manipulation. The more complicated the product
manipulation,the moreingredients to be added,the fasterthe production line
or the shorterthe productrun, the less flexiblegloveboxesbecome.Operatingon
a batchbasis,pre-disinfectedgloveboxesgivethe potentialfor a temperature-
controlled environmentwitha modifiedatmosphereif required(e.g.highCO 2 ,
low O 2 or very highO 2 concentrations), whichcan be disinfected on-lineby
gaseous chemicals (e.g.ozone)or UV light.
Gloveboxes may also offer some protection in the future to foodstuffs
identified by riskassessmentsas being particularly proneto bioterrorism.
Improvingzoningwithinfoodprocessingplants 165