ges. The objective for zone M is to control or reduce the creation of hazardous sources that can affect an associated area of
higher zone classification. Another objective is the protection
of the interior of food processing equipment from contamination when exposed to the atmosphere.
Zone H applies to an area where the
highest level of hygiene is required. A
“High Hygiene” room, which, in food
processing is the equivalent of a cleanroom, must be completely contained.
Zone H is typical for open processing,
where even short exposure of product
to the atmosphere can result in a food
safety hazard. Products and ingredients
that are processed or stored and are
destined for a highly susceptible consumer group (e.g., infant nutrition), are
instant in nature or ready for consumption. They must be handled in a refrigerated supply chain, as they are
susceptible to growth of pathogenic microorganisms. The objective for H
zones is to control all product contamination hazards and to protect the interior of food processing
equipment from exposure to atmosphere. Filtered air must be
supplied to this area.
These areas should be limited in size, must have a simple
equipment layout to facilitate process, cleaning and maintenance operations and should have utilities located outside.
However, investing in an enclosed line that brings barriers very
close to the product is more logical than trying to create a complete cleanroom around a partially open line.
Zoning and the establishment of barriers to ensure that
product of acceptable hygienic quality is produced should only
be applied where their use will help significantly to protect
products. Designing the entire factory as a cleanroom is not the
purpose of food area segregation to protect both product and
consumer. Zoning and barrier technology must be applied in an
appropriate and consistent way, thereby avoiding unnecessary
investment.
tioning and routing of processes, process supports and utility
systems. These programs allow the observer to “walk through”
the facility, seeing the inside of the facility from different angles
and locations. To save building and renovation costs, potential
problems can be solved before the onset of construction. Addi-
tionally, in the development of high
hygiene areas, computational fluid dy-
namics can help simulate and visualize
expected airflows.
To meet a possible increase of processing activities within the food plant
in the future, the building and its food
processing support systems should be
designed so they can either be expanded, or another building and/or
utilities can be added. Oversizing the
main utility systems is a common practice. If possible, the factory should also
be made adaptable (i.e., the ability to
modify the production area for other
manufacturing purposes) and versatile
(i.e., the ability to do different things
within the same room).
“ZONING AND THE STABLISHMENT OF
BARRIERS...SHOULD ONLY
BE APPLIED WHERE THEIR
USE WILL HELP
SIGNIFICANTLY TO
Construction of Facilities:
Pest Prevention
To exclude flooding and the entry of rodents, factories
should be built at a higher level than the ground outside. Exterior doors should not open directly into production areas, and
windows should be absent from food processing areas. The
number of loading docks should be minimal and be 1–1.2 m
above ground level. Preferably, outside docks should have an
overhanging lip, with smooth and uncluttered surfaces that are
sloped slightly away from the building to encourage water runoff. Areas beneath docks should not provide harborages for
pests, should be paved and should drain adequately. To provide
protection for products and raw materials, docks can be
shielded from the elements by roofs or canopies. However,
these structures can become a serious sanitation problem due to
roosting or nesting of birds. Bird spikes or nets can solve that
problem. To prevent the entry of insects, dock openings should
be provided with plastic strips or air curtains, and external lighting to illuminate these factory entrances should be placed in locations away from the factory building. Intruding insects can
still be attracted and killed within the food factory by strategically positioned ultraviolet (UV) light electric grids or adhesive
glue board traps.
PROTECT PRODUCTS.”
Construction of Facilities:
Appropriate Layout
The layout and design of the food factory must be adapted
to the hygienic requirements of a given process, packaging or
storage area. The interior of the factory must be designed so
that the flow of material, personnel, air and waste can proceed
in the right direction. As they become incorporated into food
products, raw materials and ingredients should move from the
‘dirty’ to the ‘clean’ areas. However, the flow of food waste and
discarded outer packaging materials should be in the opposite
direction. Before building begins, simulation of the flow of
people, materials, products and waste can help the designer determine the most appropriate place for installing the process
equipment and where the process and utility piping should
enter the process area. Even the simulation of maintenance and
cleaning operations can be useful to determine the most appropriate factory layout. Graphical computer-aided design and 3D
visualization programs can help in the hygienic design, posi-
Construction of Facilities:
Interior Hygienic Design
Construction Materials
Construction materials for equipment and utility piping
should be hygienic (non-absorbent, non-toxic and cleanable),
chemical-resistant (to product, process chemicals and sanitizing
agents), physically durable (unbreakable, resistant to moisture,
cold, abrasion and chipping) and easy to maintain. Materials
used to construct process and utility systems located in the
non-food contact area may be of a lower grade than those applied in the food contact zone. Surfaces that are frequently wet
