Transcript Slide 1

Unit 2: Sanitary Control of FHE
Topic: Sanitary Design & Construction
of FHE – Design of FHE
Lecture 2
Objectives
At the end of the session, students should
be able to:
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Discuss clearly issues related to FHEs not suited to existing
operations
Outline clearly the objectives of designing and constructing the
exterior of FHEs
Outline clearly the objectives of designing and constructing the
interior of FHEs
Identify accurately/Outline clearly design and construction features
of loading docks, exterior walls, interior walls, floor, roof, lighting,
ventilation, hoods/canopies, staff facilities, drains, ware washing
facilities, hand washing facilities
Food Premises Design
Very important and is dependent on:
 Nature of the operation
 Associated risk
Overview
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The design and maintenance of facilities
and surroundings of the food handling
establishment is critical in ensuring the
production of safe foods
Many FH premises were never designed
to be used as FHE
Many FH premises were never designed
with food safety in mind
Overview
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Some buildings require extensive
renovation to meet the required
standards
Potential operators of food
establishments are required to consult
with the local health authorities prior to
the operation of food handling entities
Some designs are just unsuitable and
may be difficult to redesign
Design and construction of
exterior
Objectives
 Building should be cleanable
 Design should minimize contamination
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Thatch roof
All food process/handling areas should
be sealed
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Avoid horizontal ledges or overhang
Sealing all spaces over ¼” to prevent the
entry of rodents
Design and construction of
exterior
Loading docks, platforms and receiving rooms
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Should be enclosed as much as is practicable
Should be designed and maintained to prevent the
creation of a harbourage for birds, rodents and insects
Loading docks and platform should prevent the entry of
pests
Should be at least 3 ft above GL with a 12” overhang to
prevent rodents from climbing into building
Properly installed rapid self closing doors/air curtains
should be used to prevent the entry of pest
Waste storage area should not be in this area
Design and construction of exterior
Exterior walls
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Ensure that the building is properly sealed
Cleanable material should be used
Minimize the use of corrugated materials
Choice of material may be dependent on the
extent of preventative maintenance required
Design and construction of
exterior
Roof
 Should be sealed in all cases
 Material should be cleanable
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flour warehouse
Openings in building
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Doors, windows, ventilation ducts must be sealed/ screened
Openings in roof – exhaust fans, ventilation, plumbing, electrical must
be sealed
Glass windows not encouraged
 Breakage/maintenance
 If used, should be flushed with the inside wall and remain closed
 Sills should slope away from walls and >45 angle
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Prevent birds nesting and accumulation of dust
Design and construction of
interior
Objectives
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Minimize the potential harbourage of pests
Minimize the potential accumulation of micro-organisms
Facilitate thorough cleaning
Maximize food protection
Sanitary objectives should be incorporated at the
outset
Sanitary design without maintenance is not best
practice
Design and construction of
interior
Interior walls (floor to ceiling)
 Hard, flat, smooth
 Free of crevices, cracks, pits
 Impervious/non absorbent
 Resistant to cleaning and sanitizing chemicals
 Corrosion resistant
 Durable, easily maintained, wear resistant
 Properly installed, sealed, covered
 Painted in a light colour
Design and construction of
interior
Materials used for walls
 Seamless poured concrete
 Recommended
 Should be sealed with a smooth finish
 Can be improved by painting with a semi-gloss
coat
 Specialized spraying with fibre glass recent
innovations
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Proven impervious, cleanable and durable
Design and construction of
interior
Materials used for walls
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Concrete blocks
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Should be heavy density
Properly sealed
Painted with a semi-gloss or gloss epoxy paint covering
Fibre glass panel
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Highly acceptable
Needs to be properly installed and maintained
Can be easily damaged by forklifts and heavy equipment if panel
extend to floor
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Need concrete in high impact areas
Design and construction of
interior
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Glazed ceramic tile
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Durable
Resistant to chemicals
Highly recommended for wet processing activities eg.
dairies
Wood
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Should be avoided
High porosity
Cannot be adequately sealed
General characteristics of walls
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Should be made of hard, durable,
impervious and cleanable material
Light colour painting is recommended
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Locating dirt
Facilitates cleaning
Assists in illumination
Design and construction of
interior
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Metal panels
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Not usually recommended due to condensation
problem
Expansion/contraction make maintaining the seal
difficult
Zinc may flake and contaminate product
All joints and junctures should be sealed
Junctures should be coved with a radius of 1” or more
Sanitary cove should have a smooth flush connection
Sanitary cove
Design and construction of
interior
Ceilings
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Often ignored
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Must be ceiled
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Need preventative maintenance programme
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Improperly installed ceilings, ceilings that promote
condensation, or those poorly maintained can
increase the potential for food contamination
Design and construction of
interior
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Suitable ceiling include:
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Board, ply board, gypsum, celotex, cement
concrete
Advantages
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Prevent contamination of food, equipment and
surfaces
Increase temperature control
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Improve comfort of staff
Increases aesthetics
Facilitates easy cleaning
Design and construction of
interior
Floors
 Most difficult surface to maintain
 Smooth (not pitted)
 Impervious, non absorbent
 Corrosion resistant, cleanable
 Should be adequately sloped to enhance
drainage (1/8 – ¼ of an inch per ft)
 Non slip
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Rubber mats can be used, but must be maintained
Maintenance of Floors
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Should be cleaned as often as necessary
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Wood, carpet and linoleum unacceptable
Suitability dependent on nature of operation & degree
of trafficking
All floors should be hard, durable, nonabsorbent, smooth but non-slip, free from open
joints, cracks, pits or unevenness of surface
Once floor integrity compromised then microbes
will harbour especially in wet areas
Tiled floor additional maintenance cost as grout
will erode
Design and construction of
interior
Drains
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Major source of microbiological contamination
Adequate numbers and size needed
Appropriately located
Designed and installed to be cleanable
Maintained in good repair
Should be enclosed
Areas around drain covers should be smooth and
maintained
Design and construction of
interior
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A trapped floor drain is needed for every
400 sq. ft. of floor area
Length of trench to the drain should not
be more than 15ft
Drains should be enclosed
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Necessary action should be taken to prevent
the entry of insects/pests via this route
Maintenance is important
Design and construction of
interior
Lighting
 Generally man’s efficiency is dependent
on the amount of light in the environment
 Light necessary to prevent accidents,
improve productivity and reduce waste
Design and construction of
interior
Characteristics of satisfactory lighting
 Adequacy - intensity
 Distribution – work area and field vision
 Uniformity – distributed over task
 Constancy – absence of flicker
 Absence of glare – undue brightness
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Light intensity on the task in relation to the field of vision should be
no more than 3:1
Design and construction of
interior
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Lighting
Area
Light Intensity (FC)
Raw material receiving
20 -30
Warehouse/bulk storage
30- 40
Processing areas
55-65
Product inspection
110-130
Packaging
70-80
Finished product warehouse
20-30
Cafeteria
40-50
Locker rooms/rest rooms
30-50
Design and construction of
interior
Area
Light Intensity (FC)
Dishwashing area
30 – 45
Meat cutting area
50 – 60
General areas
50 – 75
Design and construction of
interior
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Both natural and artificial light necessary
Window space should occupy a minimum of
20% of floor space
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Prepare foods in a sanitary manner
Avoid spills
Facilitate cleaning
Cleaning of utensils
Hand washing
Design and construction of
interior
Lighting
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Need correct types of light fixtures
Shatter proof shield or break resistant
lenses
Designed to be moisture resistant
Cleanable
Design and construction of
interior
Ventilation & AC systems
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Maintain temperature and RH
Should prevent condensation
 As well as employee comfort
Proven to be a source of contamination
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Listeria monocytogenes
Construction, design, cleaning and general
maintenance very important
Air velocity 40 – 50 ft/min
Design and construction of
interior
Ventilation & AC systems
 Vents should not draw air from a dirty
area
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Eg. Staff restroom, chemical storage area,
area with bird dropping
Adequate filters should be installed and
changed as per recommendation
Ductwork should be designed outside the
processing areas
Design and construction of
interior
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Hoods or Canopies
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Used for the removal of heat, moisture, steam
Size and height above heat source important
Need 2 ft. overhang for each ft. above equipment
Usual clearance 5ft. above equipment and a
minimum of 6’-3’’ where workers pass beneath
Should be smooth, free of crevices and projections
Should be supported to equipment, wall, ceiling
Preventative maintenance important
Design and construction of
interior
Ware washing facilities
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Located to provide easy access from
dirty areas
Flow of activities should take place from
dirty to clean areas
Adequate drainage should be provided
Design and construction of
interior
Hand washing sinks
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Conveniently located
Adequate numbers
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Constructed and installed to meet plumbing codes
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Based on size and types of operation
1 for every 40sq.ft. / for every principal food area
No back flow (air gap)
No submerged inlet
Trapped
Foot operated highly recommended
Provided with hot & cold water
Design and construction of
interior
Hand wash sinks
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Avoid wooden frames
Avoid pipes with intermittent supply of
water
Should preferably be stand alone units
Soap, single use hand drying towels,
covered waste receptacle
Design and construction of
interior
Employee facilities
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Adequate numbers should be provided
Personal belongings should not be stored in food service
areas
Should be constructed and maintained in a sanitary
manner
Top of lockers should be sloped instead of being flat
Lockers should be sealed to wall
Should not open directly to processing areas
Most instances a two door separation required
Design and construction of
interior
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Toilet facilities should be provided for staff
and patrons, for each sex
Street clothes should not be hung in toilet
rooms
Change rooms should be equipped with the
basic amenities
Water Closets
No. of employees
(each sex)
No. of fixtures
1 – 15
1
16 – 35
2
3
4
5
6
36 - 55
56 – 80
81 – 110
111 - 150
1 fixture for each additional 40 employees. Urinals may be provided in lieu 1/3rd no. of wc
Summary
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The intended operation of FHEs need to
be carefully envisioned
The intended operation influence the
design of the FHE
Interior and exterior design influence
the safety of operations conducted
within a FHE