We, WONE, a supplier of hygiene cleaning and sanitation equipment as well as hygiene solutions for the food industry, are going to share our ideas of what should be paid attention to in the internal planning and design of a food dust-free workshop in the food plant.
01
Food dust-free workshop structure
Food processing and purification workshops are mainly steel-concrete or brick-built structures, and according to the needs of different food products, the structural design should be suitable for the special requirements of specific food processing.
The space of the workshop should be adapted to the production. Under normal circumstances, the per capita area of processing employees in the production and purification workshop (excluding equipment) should not be less than 1.5 square meters. Too crowded purification workshops not only hinder production operations but also cause collisions between personnel and contact between personnel work clothes and production equipment, which can easily cause product contamination. The ceiling height of the workshop should not be less than 3 meters, and the cooking room should not be less than 5 meters.
The hygiene facilities of the processing area and the processing employees, such as changing rooms, showers room, and toilets, should be a joint structure in the building. The cold storage and processing area of seafood, meat, and quick-frozen foods should also be a joint structure.
02
Purification workshop layout
Food processing purification workshops are mainly steel-concrete or brick-built structures. According to the layout of different purification workshops, it is necessary to facilitate the connection between various production links and the sanitation control of the processing process to prevent cross-contamination in the production process.
The food processing process is basically a process from raw materials → semi-finished products → finished products, that is, from non-clean to clean.
Therefore, the production of the processing workshop should be laid out in principle according to the processing sequence of the product, so that the product processing transitions from the unclean link to the clean link, and cross-flow and backflow are not allowed in the processing process.
Corresponding isolation measures should be taken between the clean area and the non-clean area to control the flow of people and logistics between each other, so as to avoid cross-contamination. The processed products are transferred through the transfer window. In the appropriate place in the workshop, a tool cleaning and disinfection room should be set up, and a cleaning tank, disinfection tank and rinse tank for tool cleaning and disinfection should be configured. If necessary, hot and cold water should be supplied, and the temperature of the hot water should not be lower than 82℃.
03
Purification workshop floor, wall, ceiling, doors and windows
The floor of the workshop should be paved with non-slip, solid, impermeable, easy-to-clean, and corrosion-resistant materials. The surface of the floor of the purification workshop should be flat and free of water. The level of the entire floor of the workshop should be slightly higher than the floor level of the factory area during design and construction, and the floor has a slope.
The walls of the workshop should be paved with a wall skirt of more than 2 meters, and the walls should be paved with corrosion-resistant, easy to clean and disinfect, solid, impermeable materials and coated with light-colored, non-toxic, waterproof, mildew-proof, not easy to fall off and washable materials.
The curvature radius of the corners, ground corners, and top corners of the purification workshop should not be less than 3 cm in arc shape. The materials used for the top of the purification workshop should be easy to clean. In the working area where water vapor is generated, the materials used for the top should not be easy to condense water balls. Appropriate arcs should be formed during construction to prevent condensed water from dripping onto the products. The doors and windows of the workshop have insect-proof, dust-proof, and rodent-proof facilities, and the materials used should be corrosion-resistant and easy to clean. The windowsill should be at least 1 meter above the ground and have a 45-degree slope.
04
Water supply and drainage facilities
The water supply pipes for production water in the purification workshop should be made of pipes that do not easily rust, and the water supply direction should be opposite to the processing direction, that is, from the clean area to the non-clean area.
The water supply pipes in the purification workshop should be as uniform as possible, and the cold water pipes should avoid passing above the operating table to prevent condensed water from condensing and dripping on the products. In order to prevent unclean water outside the water pipe from being siphoned and backflowing into the pipe, a vacuum eliminator must be installed at the appropriate position of the water pipe. The drainage ditch in the purification workshop should be paved with smooth and impermeable materials. No unevenness and cracks should appear during construction, and a 3% inclination should be formed to ensure smooth drainage in the workshop. The drainage direction is also from the clean area to the non-clean area.
The drainage ditch should be made of movable grates made of rust-proof materials. The floor drain of the workshop drainage should have measures to prevent solids from entering. The scalding and feathering room of the livestock and poultry processing plant should use open ditches to facilitate the removal of feathers and sewage. The outlet of the drainage ditch should be equipped with a rat-proof mesh cover. The outlet of the floor drain or drainage ditch in the cleanroom should use a U-type, P-type, S-type, or other water seal with a trap to prevent insects and odor.
05
Ventilation and lighting
The cleanroom should have good ventilation conditions. If natural ventilation is used, the ratio of the ventilation area to the floor area of the cleanroom should not be less than 1:16. If mechanical ventilation is used, the air exchange volume should not be less than 3 times/hour. If mechanical ventilation is used, the airflow direction of the cleanroom should flow from the clean area to the non-clean area. For the cleanroom relying on self-lighting, the ratio of the window area of the cleanroom to the area of the cleanroom should not be less than 1:4.
The illumination of the processing table in the cleanroom should not be less than 220Lux, and the illumination of other areas of the workshop should not be less than 110Lux. The illumination of the work surface of the inspection workplace should not be less than 540Lux. The illumination of the light inspection work point of bottled liquid products should reach 1000Lux, and the light should not change the original color of the processed object. Workshop lamps must be equipped with protective covers.
06
Temperature control facilities
Workshops that process perishable and easily deteriorating products should be equipped with air-conditioning facilities. The temperature of meat and aquatic product processing and purification workshops should not exceed 15℃~18℃ in summer, and the temperature of meat pickling rooms should not exceed 4℃.
Tools and equipment: The materials used in the processing of equipment and tools, especially mechanical equipment, operating tables, conveyor belts, pipelines, and other equipment that come into contact with food, and tools such as baskets, trays, and knives should meet the following conditions: – Non-toxic, will not cause pollution to the product; – Corrosion-resistant, not easy to rust, not easy to age and deform; – Easy to clean and disinfect; – The materials of the hoses used in the workshop must meet the requirements of relevant food hygiene standards (GB11331-89).
The structure of food processing equipment and tools should be designed to facilitate daily cleaning, disinfection, inspection and maintenance. When designing and manufacturing tank equipment, it must be possible to ensure that the contents are emptied. The installation of processing equipment in the cleanroom should, on the one hand, meet the requirements of the entire production process layout, and on the other hand, facilitate the hygienic management of the production process, and at the same time facilitate the daily maintenance and cleaning of the equipment.
07
Personnel sanitation facilities
(1) Dressing room cleanroom
There should be a dressing room suitable for the number of processing personnel, and the dressing room should be connected to the workshop. If necessary, dressing rooms should be set up for processing personnel working in the clean area and the non-clean area and the passages for entering and exiting their respective work areas should be separated. Personal clothes and shoes should be placed separately from work clothes and boots.
The hanger should keep the work clothes hung on it at a certain distance from the wall and not touch the wall. The dressing room should maintain good ventilation and lighting. The indoor air can be sterilized by installing ultraviolet lamps or ozone generators.
(2) Shower room
The processing and purification workshop of meat products (including canned meat) should be equipped with a shower room connected to the purification workshop. The size of the shower room should be adapted to the number of processing personnel in the purification workshop, and the shower head can be configured at a ratio of 1 for every 10 people.
The shower room should be well-ventilated. The floor and wall skirts should be constructed of light-colored, easy-to-clean, corrosion-resistant, and impermeable materials. The floor should be non-slip. The part above the wall skirt and the top surface should be painted with anti-mildew paint. The floor should have smooth drainage, good ventilation, and a hot and cold water supply.
(3) Hand washing and disinfection facilities
The entrance of the workshop should be equipped with hand washing and disinfection facilities that are suitable for the number of people in the cleanroom. The number of hand washing faucets required should be 1 for every 10 people and 1 for every 20 additional people above 200 people. The hand washing faucet must be a non-manual switch. There must be a soap dispenser in the hand washing area, and hot water should be supplied. The water output should be warm. The number of containers for hand disinfectant should also be suitable for the number of users and should be placed reasonably for easy use.
Hand-drying utensils must be items that will not cause cross-contamination, such as disposable paper towels, disinfected towels, etc. A sufficient number of hand washing and disinfection facilities and corresponding hand drying supplies should be installed at appropriate locations in the clean room so that workers can wash their hands and disinfect them regularly during production operations, or wash their hands in a timely and convenient manner after getting their hands dirty. The water discharged from the hand washing area cannot flow directly on the ground but must be introduced into the drain pipe through a water seal.
(4) Toilet
In order to facilitate production hygiene management, the toilet connected to the clean room should not be located in the processing area but can be located in the dressing area. The doors and windows of the toilet cannot be directly opened to the processing area. The walls, floors, doors, and windows of the toilet should be built with light-colored, easy-to-clean and disinfect, corrosion-resistant, and impermeable materials, and equipped with flushing, hand washing, and disinfection facilities, and windows with insect and fly protection devices.
08
Storage facilities: raw and auxiliary material warehouse
The storage facilities for raw and auxiliary materials should be able to ensure that the quality of the raw materials and auxiliary materials prepared for production and processing will not change during storage, affecting production and use, and causing new safety and health hazards. Cleanliness, hygiene, and prevention of rodent and insect damage are basic requirements for storage facilities for raw materials/auxiliary materials for various types of food processing.
For more information about food factory safety and sanitation planning, please feel free to communicate with us!
When placing larger equipment, a certain distance and space should be kept between the dust-free equipment and the wall, and between the equipment and the ceiling to facilitate the entry and exit of equipment maintenance personnel and cleaning personnel.
