 Processing, packaging or packing of fresh cut produce takes place in diverse locations and physical structures and on many different scales. It is well recognized that field trimming and infield preparation are integral parts of the overall industry. For the purpose of this presentation, this section discusses the layout of a facility and how product moves through a facility. The overall design of the facility from receiving area to shipping dock is an important consideration in eliminating opportunities for chemical, physical and microbial contamination. Both direct contamination and cross contamination of product can be minimized with proper attention to physical design, construction material selection and facility traffic flow. The building should be designed so that incoming raw products never cross paths or commingle with finished products. While this is a recommended practice for all produce operations, it is especially important in a fresh cut operation. Occasionally, the available space is limited, but physical separation of zones using walls or other barriers can achieve adequate separation. In addition, separate or segregated zones for chemical storage and mixing and maintenance and fabrication shops are recommended. A properly designed facility is important because the additional cutting, washing, mixing and packaging steps that may be part of fresh cut produce preparation increase the opportunity for cross contamination from the raw, unwashed produce. Unwashed produce should never contact the same surfaces that will contact produce at any later step of the process. Palettes and bins coming directly from the field may also be a source of contaminated soil and plant debris. Proper facility design can significantly reduce this potential hazard. Finally, processed but unprotected product should not be stored in the same cold room location with raw produce or dirty containers and palettes. For example, the facility should have sufficient cold room space to keep processed product, which is being held for later mixing and packaging, separate from incoming and stored raw materials. The key element is to ensure that unwashed produce enters at one separated area, moves through the facility without contacting produce or equipment in earlier stages, and exits at a terminal segregated shipping area. Like the overall facility design, the movement of processing water, waste streams, air flow and employees should be planned with food safety in mind. To conserve water and minimize wastewater discharge, many facilities recirculate water. We will discuss more about water in a later section. When water is recirculated, incoming clean water first contacts clean finished product and moves opposite to product flow, where it is used to wash and cool incoming raw produce before the water is discharged. In a similar manner, facilities may design and install an air filtration system for central distribution and air flow counter to product flow. In these systems, clean filtered air moves with a positive pressure from the cleanest areas, packaging and packing, back toward the receiving area. Positive pressure flow, backward air flow, helps reduce the chance of airborne contamination along the linear facility design. In the same manner, there should be negative air pressure in the restrooms to keep air from flowing out of the restrooms. Additional air flow barriers, such as air curtains, help to isolate receiving and shipping areas that may be open to the outside environment. Processors that use a bulk dump for incoming materials should consider installing a fixed wall with a pass-through to move produce from outside to inside the facility. This point of separation will reduce the potential for water moisture or aerosol in air above or around the dump tank from contaminating the inside of the processing area during receipt of incoming materials. Traffic flow from the outside environment and within the facility should also be carefully planned. Equipment and workers should not move between segregated areas. Cross-contamination can be avoided by preventing the movement of lift trucks, bins, totes, tools, cleaning implements, clothing and people from receiving or storage zones to processing and packaging areas. Color-coding bins, totes, clothing, cleaning tools and other items can help achieve this separation of traffic. Finally, proper facility design and selection of construction materials are major contributors to safe fresh-cut processing. Floor should be designed for easy cleaning. A smooth, non-porous floor with coving at wall junctions prevents the entrapment of dirt and debris. Expert advice should be sought to select materials that facilitate cleaning and sanitation and to design adequate floor slope for drainage. Flooring materials should be suitable for a fresh-cut facility and selected to be resistant to chemical damage and cracking from equipment movement. Cracks in flooring are difficult to clean and may easily become a site for plant residue accumulation and subsequent microbial growth. Walls should be designed for and constructed of materials that are readily cleaned and will not serve as a home for pests. Ceiling and screening should be used to exclude pest entry through windows and vents. Consideration should be given to permanently enclosing pre-existing windows in a space that is being converted to fresh-cut processing and packing. Any access doors leading directly from outside the facility to the processing and packaging area should be designed with food safety in mind. An effective design utilizes a double entry barrier, sometimes in combination with a forced air curtain, to help exclude insects. In this design, each person should enter self-closing doors which open in opposing orientation, left to right, then right to left. The doors leading directly to the outside should first close to allow the second door to open. Cautionary signs and boot dips alert the worker or maintenance person that they are entering a clean area. The use of such doors during operating hours should be strictly controlled. The areas outside the facility should be designed and maintained to minimize the potential for attracting or harboring rodents and other potential sources of human pathogens. Landscape design and weed control programs should be a part of the overall food safety plan. The location and design of drains, floor flumes, and pipelines can be made to greatly improve the ease of maintenance and effectiveness of cleanup procedures. Expert advice should be sought to design placement or protective aids to prevent pipe and wall condensation from becoming a source of contamination. Drain should be fitted with seals and grates capable of preventing rodent entry. The use of floor flumes should receive careful consideration because of the potential for water aerosol contamination of the room air or nearby equipment surfaces. This is especially true for floor flumes that carry produce and water waste from one segregated area across another. Floor flume transfer from an adjacent produce cooling and packing operation into and across a fresh cut facility should be avoided. The design of the collection area for waste stream water should incorporate systems to prevent product or equipment contamination that might serve as an attractant for pests.