gel coatsare on the market.One high-endmaterial is Arcoplast, which consists
of sandwich composite panels thatare manufacturedwithdifferent coring
materials suchas foam,honeycomb,cementor solidglass matrixto suit the
user'srequirements.The panelcoresare reinforced on bothsides withmultiple
layersof glassfibersembeddedin a permanentdurablepolymer resinand
finished witha hard,high-gloss gel coat resin.It has incorporated antimicrobial
features usingsilverion technology.It is highlysuitablefor highlymicrobial-
sensitive areasin a foodor pharmaceuticalfacility.Anothertypeof application
is calledStayflex. It consists of a spray-onfoaminsulationthat is thencovered
witha resinand gel coat that is extremely hardand damageresistant. This type
of applicationworkswellfor renovationprojectswithexisting walls that are
uneven, haverust, peelingpaint and hidden niches thatcan hide dirt and
microbes. Thisspray-onfoamwill fill the holes and eliminatea hidingplacefor
pests.Otherwallmaterials are reinforced fiberglass boardthat has beenaround
for a number of years.This material has a smoothnon-absorbentsurfaceand is
easilycleanable.It is, however, susceptibleto damageby forklifts,troughs,
carts,etc., banging into it and it mustbe protected.
Constructing internal walls regardless of the type of material should be
considered carefully. Manycontractorswant to do it the easywayby erecting
the wallfromfloorto ceilingand thenpouringa concrete curbwallagainst the
erected wall. Thisprotects the panelmaterialfromdamagebut creates a joint
between the concrete and the panelmaterial. In a facility that useswaterfor
processing wherethereis splashing, moisturewill collectbetweenthe curbwall
and the wallpanel. Thismakes an excellent growtharea for mold,bacteriaand
yeast.In refrigerated roomsthis can become a growth area forListeria. A better
methodis to poura stub wall witha covedbaseor installa precastcurbwall and
set the wallpanelson top in a stainlesschannel that has beenfilledwithcaulk.
The caulkwill prevent moisturefromcollectingand seal the jointbetweenthe
bottomof the paneland the channel. If insulation is required in the stub wallit
can be incorporatedin the precaststubwall. Insulation is required if thereis a
largetemperaturedifferential between the two roomsthe wallis separatingto
preventcondensate formation (see Fig. 10.1).
Newideasand materials for walls and wallcoverings in foodprocessing
facilities are continually appearing.Oneonlyhas to attendsome of the many
tradeshows every year to discover newideas,materials and applications.
Sanitation and sanitary (hygienic) design are well up the list of criteria
considered when designing a new facilityor renovatingor addingto an existing
facility.The old ideathat floors, wallsand ceilingsare just part of a necessary
envelopeto hold the equipmentis fast disappearing.Theyhaveto be considered
as an integralpart of the sanitationprogramand mustbe easyto clean,do not
contributeto contaminationor adulterationof the product or products being
processed/packaged. As saidin the beginningof this chapter, wallsare the
second mostabused surfacein a foodprocessingplant and this mustbe taken
into consideration.
Improvingthe designof walls 189