Glossary and Abbreviations - Unido

prevent operators leaving cleaning cloths or other items lying there, which can attract
insects.
Storeroom doors should not have gaps beneath them, and should be kept closed to prevent
insects and rodents from getting in and destroying stocks of crop. Normally doors in
processing rooms should be kept closed, but if they are used regularly there is a tendency
for them to be left open, allowing animals and insects to enter the plant. Thin metal chains,
or strips of plastic or cloth can be hung from door lintels to deter insects and some animals,
while allowing easy access for staff. Alternatively, mesh door screens can be fitted.
Floors
Floors in processing rooms and storerooms should be made of good quality concrete,
smooth finished and without holes or cracks. Paints can protect floors, but vinyl-based floor
paints are expensive. Red wax household floor polishes wear away easily and could
contaminate products. The best way to protect floors is to clean up spillages as they occur
and make sure that the floor is thoroughly washed after each day’s production.
Dirt can collect in corners where the floor and the walls join. To prevent this, the floor should
be curved up to meet the wall. The floor should also slope to a drainage channel. Proper
drainage prevents pools of stagnant water forming, which would allow insects to breed. The
drainage channel should be fitted with metal gratings that are easily removed so that the
drain can be cleaned. Rodents and crawling insects can also get into the building through
the drain, and a wire mesh cover should be fitted over the drain opening. This too should be
easily removed for cleaning.
Services
Lighting and power
Where lighting is needed and electricity is available, florescent tubes use less electricity than
light bulbs. Power points should be located at least one metre above the floor so that there is
no risk of them getting wet when the floor and equipment is washed down. Ideally,
waterproof sockets should be used. Each power point should only be used for one
application, and multiple sockets should not be used because they risk overloading a circuit
and causing a fire. All plugs should have fuses that are appropriate for the power rating of
the equipment, and the mains supply should have an earth leakage trip-switch. Cables
should be properly fixed to walls or run vertically from the ceiling to machines. There should
be no exposed wires at any connection. Larger electric motors should be fitted with a starter
and isolator.
Water supply and sanitation
Water is essential in all root crop and tuber processing for washing crops and equipment. An
adequate supply of potable water should be available from taps in the processing room.
There are two potential problems with the water quality: sand and contaminating microorganisms.
If a processing unit is located in a rural area, there may be no mains supply, or it
may be unreliable or contaminated. Water from boreholes is likely to be relatively free from
micro-organisms, but may be contaminated with sand. River water is likely to be
contaminated with micro-organisms and should only be used if no other source is available.
Samples of water should be periodically checked (e.g. once per year) for microbial
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