design

1. 1
FOOD PLANT LAYOUT
Design and Construction of Factory
Building
DR. JAVAID AZIZ AWAN

2. 2
Design and Construction of Factory Building
Design of Factory Building
 Factors considered
Construction of Factory Building
 Floors
 Drains
 Walls
 Doors and Windows
 Ceiling
 Ventilation
 Lighting
 Auxiliary Facilities

3. 3
DESIGN OF FACTORY BUILDING
Design - key role in economic and hygienic handling
and processing food raw materials
Suitable design premises prepared by experts
 Must protect food from spoilage
 Must safeguard consumer health
 Ensure safety of employees
Competent engineers to execute
Structure must meet environmental and operational
requirements
Basic recommendation –
"plan before you build".

4. 4
Factors considered for Good Design
1 Proper installation of equipment
2 Uninterrupted, smooth movement of
personnel
3 Uninterrupted, smooth movement of raw
material
4. Uninterrupted, smooth movement of semi-
finished products
5. Uninterrupted, smooth movement of finished
products

5. 5
Factors considered for Good Design
6 Hygienic operations from arrival of raw
material to dispatch of finished products
7 Prevention of cross-contamination from raw
materials to finished or semi-finished
products
8 Prevention of insect pests and rodents from
entering into working and storage areas
9 Adequate cleaning of premises.

6. 6
CONSTRUCTION OF FACTORY BUILDING
Must be undertaken by experts who understand
nature of operations to be performed
Some industries require constant use of water,
detergents, chemicals, heat and steam
Consequently, regular production of fumes and
water vapours inside premises
Such industries need special care in selection
of materials for construction.

7. 7
Construction of Factory Building - Contd
Civil/building engineer must be advised:
 on specific needs of food processing plant
 importance of construction material to be
used
This material must be able to withstand:
corrosive nature of water, steam, chemicals,
and detergents employed.

8. 8
Construction of Factory Building - Contd
Additionally:
 should not impart odours
 Should not cause health hazards to workers
 Should not aid in development and growth of
microorganisms in premises
Care be taken in design and construction of every
individual item of building - floors, drains, walls, doors,
windows and ceiling
Attention paid towards proper ventilation and lighting
Adequate provision of auxiliary facilities - cloak
rooms, toilets and storage rooms, essential for
hygienic and economical food processing.

9. 9
Floors
Proper construction and finishing of floors
important for hygienic production of food and
safety of workers.
Wording July 1992 EEC Directive very clear:
In rooms where food is prepared, treated
or processed (excluding dining areas), the
floor surface must be made of impervious,
non absorbent, washable and non toxic
materials; they must be maintained in a
sound condition and they must be easy to
clean and disinfect".

10. 10
Floors - Contd
Additionally:
Floor surface be sufficiently slip resistant under
all service conditions to meet worker safety
 First essential requirement - floor surface be
made of impervious and non-absorbent
material
 This precludes use of structural concrete or
pure cement mortar for joints between tilings.

11. 11
Floors - contd
Two key reasons why floor surface material must be
non-toxic:
 1. Due to trafficking over time, minute particles of
floor surface become detached
Swept up by cleaning, washing operations
 Transported into ground water, rivers, streams
through drainage system
 2. Some resin based materials, though in hardened
state, not always fully cured, still contain small
amounts of volatile and toxic solvents
can escape into surrounding atmosphere, with
possible risk to both workers and food stuffs.

12. 12
Floors - Contd
Right after roof failure, floor failure probably second
most common source of accidents in an industry
Too slick floor, exposes workers to risk of falls
Over 20% of all worker accidents due to falls caused
by slippery nature of floor, when wet.
Floor has to withstand abuse, technically known as
"shock", that equipment, processing operations and
employees dish out
Shock roughly divided into:
 chemical
 thermal
 physical.

13. 13
Floors - Contd - Chemical shock
Comes from products or processing
Processing involves adding or subtracting
chemicals
Fruit pieces, vinegar, brine, acidic or alkaline
solutions - can cause floor problems
Cleaning agents - most common source of
chemical shock

14. 14
Floors - Contd - Chemical shock
Some floor materials have medium term resistance to
acids used or found naturally in drinks and foodstuffs
Others have low resistance to sodium hypochlorite
(bleach) or hydrogen peroxide, common disinfectants
CIP fluids, wash-down solutions, other cleaning
chemicals often liable to erode floor coverings
Situation worse with advent of nitric acid-based
cleaning solutions
Replacing phosphoric acid for environmental reasons,
while safer in wash water, harder on painted surfaces.

15. 15
Substances affecting floors in different food industries
Animal systems - Milk, butter, cheese, raw cream,
ice-cream, sausages, fish, meat, processed foods,
pickles, etc.
 Substances Affecting - Lactic acid, butyric acid,
acetic acid, fat, grease, blood, salt, sugar
Intermediate system - Mayonnaise
 Substances Affecting - Edible oil, vinegar, butyric
acid, amino acids, lactic acid, and sugar
Plant systems - Carbonate drinks, seasonings, etc.
 Substances Affecting - Sugar, sodium carbonate,
hydrochloric acid, caustic soda.

16. 16
Floors Contd – Thermal Shock
Occurs when sudden heat makes covering
expand or shift at different rate than concrete
beneath
Cleaning plays large part in thermal shock
Use of steam or hot water to wash down floors,
equipment or walls put tremendous strain on
floor coverings
Laying hot water hose on floor stress covering
Processing spills of hot liquid or fat have
similar effect, intensified in refrigerated or
frozen environment.

17. 17
Floors Contd – Physical Shock
Ranges from footsteps to gouges from hand
trucks
Amount of traffic floor expected to bear - a
crucial factor in specifying topping
Physical shock can result in sanitation problems
High-traction floor can become porous,
microorganisms can burrow into pores, creating
sanitation problem
Certain floor materials and joints do not stand
up well to high-pressure hot water washing.

18. 18
Floor Contd - Materials
Must recognise each type of material has its
place in food and drink production facilities
More important analysis that must be made for
each project to ensure that correct choice from
both economic and technical points made
Key criteria considered in analysis:
 a. Regulatory Criteria (Health and Hygiene and
Worker Safety)
 b. Durability Criteria

19. 19
a. Regulatory Criteria (Health and
Hygiene and worker Safety)
Impermeability characteristics
Absorption characteristics
Resistance to mechanical shock
Anti-slip characteristics
Ease of cleaning and disinfecting

20. 20
b. Durability Criteria
Chemical resistance - especially acids,
grease, detergents, disinfectants
Thermal shock resistance
Resistance to abrasion, scratching and point
loading (puncture).

21. 21
Floor materials -contd
Different materials or types of floors may be
constructed depending upon usage and stress
or shock likely to receive
Type of materials used for floor surface finishes
in food and drink production facilities:
 Polymer modified cementitious screeds
 Resin screeds and mortars
 Tilings
 Stainless steel sheets
The choice of material depends upon industry
and investment.

22. 22
Floor materials - contd
Epoxy floors – Most important ingredient is
"aggregate" - material added to epoxy to increase
traction
Some flooring systems have aggregate already
added, others allow choice
Probably most common choice silica sand -
economical, versatile but vulnerable to physical and
chemical attack
Other aggregate choices include garnet, bauxite,
emery, carborundum and aluminium oxide, - allow
good traction, durable, but expensive
Epoxy floors suitable for food and drink industries.

23. 23
Floor materials - contd
Tiled floors – Tiles with porosity of virtually zero
available for food industry
Combined with high compressive strengths of both
tile and installation materials leads to high strength,
durable, virtually stainless and trouble free floors
Some tile manufacturers provide guarantee for 10
years with actual life expectancy far greater
On a like for like basis, including screeds,
construction time, durability requirements, tiled floors
compare very favourably
Tiled floors safe, hygienic, long lasting and cost
effective
Suitable for beverage and dairy industries.

24. 24
Floor materials - contd
Stainless steel sheet floors – durable, non-
toxic, quite expensive
Commonly used in Pakistan in baking industries
Can be slippery
Safety issue?

25. 25
Drains
Drains be adequately located
Drains designed such that are ventilated to
outside atmosphere
Should also be constructed to prevent entry of
insects and rodents inside premises
Slope of about one in fifty (quarter inch per
foot) usually sufficient for easy flow of liquid
wastes through drain.

26. 26
Walls
Wall surface be smooth, easy to clean
Have a finishing of waterproof, non-absorbent,
non-toxic and washable surface especially in
industries that employ water for various
purposes, - fruit, vegetable, meat, milk
processing
In flour milling where no water used in
processing areas, surface should not allow
accumulation and building up of dust released
Junction of wall and floor be curved or sloped -
- encourage easy cleaning and draining.

27. 27
Doors and Windows
Doors be self-closing type, closely fitting
In case outside doors frequently used, then
suitable wire netting essential to prevent entry
of insects into premises
Windows be fitted with screens and constructed
so that would not permit accumulation of dust
Internal sills be sloping to prevent their use as
shelves and avoid collection of dirt.

28. 28
Ceiling
Improperly constructed ceiling can be a
nuisance in food manufacturing plants
Should be designed to prevent accumulation of
dirt and minimise condensation of water
vapours - otherwise encourage flaking,
development of moulds
Now fashion to install false ceilings in buildings
Such ceilings harbour dust, serve as nests for
rodents, birds and insects
May cause problems in ventilation and lighting
Hence undesirable in food industries.

29. 29
Ventilation
Required:
 for removing noxious odours, fumes, dust, etc.
 supplying fresh clean air
During food processing smoke, fumes, vapours, dust
produced - must remove from processing areas, since
food materials readily acquire odours
Where variety of food products handled and
processed, place must be well ventilated
Poorly ventilated premises lead to condensation,
support microbial growth on walls and ceilings
Exhaust boxes, retorts etc be provided with hoods
connected with system to carry vapours outside
Mechanical exhaust fans commonly employed
Provision for supply cool air to workers in hot season.

30. 30
Lighting
Adequate lighting beneficial for product quality
 Helps in proper processing operations
 Helps in detecting dirty locations
 Helps safeguard food and the consumer
Natural light most preferable
Where not possible, working area be
adequately lit with artificial light such as
fluorescent.

31. 31
Auxiliary Facilities
Provision for cloakrooms, sanitary facilities required
Where applicable, workers be allocated with suitable
space for changing into working outfit, keeping
outside clothes and hand baggage
Provision for rest, washing in cloakroom needed
Adequate sanitary facilities for workers needed,
locate away from handling and processing areas
Provide hand washing facilities - supply of running
potable water, suitable detergents, disinfectants
and/or antiseptic lotions
Disposable towels, continuous roller towels or hot air
hand dryers to dry hands required
Notices at appropriate locations informing workers
on need to wash hands after using toilet.

32. 32
Auxiliary Facilities - Contd
Provision needed for storage purposes.
 Raw materials
 Semi-processed foods
 Finished products
Suitable well-ventilated vermin-proof stores with
shelves - adequate for most stable and semi-
perishable commodities
Cold stores or freezers necessary for
perishable and prepared foods
Design of stores must ensure all areas easy to
access and clean.

33. 33
Auxiliary Facilities - contd
Quality control laboratory - essential part of
food processing plant
Allocate adequate space
Provision in QC lab:
 chemical
 microbiological and
 sensory evaluations
Preferably locate adjacent to processing areas
Reserve suitable space for prayers.

34. 34
Thank you
End of Design and
Construction of Factory
Building

35. 35
Next Topic
Food Plant Equipment