One of the most important factors to consider in the design and modification of establishments is the plumbing system. If the plumbing system is not properly installed , contamination of products can occur from flooding, back siphonage, stoppages and cross-connections with the potable water system. This chapter provides guidelines concerning the plumbing facilities, in meat and poultry establishments. For additional information on the design and modification of plumbing facilities, consult the National Plumbing Code.


1. Hose Connections and Hoses

There should be enough conveniently located hose connections with steam and water mixing valves or hot water connections provided throughout the establishment for cleaning purposes. Hose connections are important in promoting routine cleaning of the establishment. Consider the following guidelines when determining how many hose connections, location of hose connections, and storage of hoses:

  • The number of hose connections depends on the number of drains.
  • If a shut-off nozzle is provided on the hose after the hot and cold water mixing valve, the vacuum breaker at the hose connection to the mixing valve will not work. Vacuum breakers should be installed on the hot and cold water supplies prior to the mixing valve to prevent such problems.
  • Hose connections should be provided with vacuum breakers to prevent back siphonage.

2. Establishment Drainage System

There need to be efficient drainage and plumbing systems for the prompt removal of liquid and suspended solid wastes from the processing environment. Consider the following guidelines when designing or modifying your drainage system:

  • All plumbing should be sized, installed and maintained in accordance with applicable state and local plumbing codes, ordinances, and regulations.
  • Drainage lines should be located so that if leakage occurs, it will not affect product or equipment.

3. Floor Drains

All parts of floors where operations are conducted should be well drained. There are two basic types of drains: point drains and trench drains. Point drains, the most commonly used drain in most areas, are located in strategic points in the room with the floor sloped toward the drain. The waste water flows over the surface of the floor until it reaches and is carried away by the drain. Trench drains involve a trough or trench that collects the waste from a larger area and directs the flow to a drain opening. The flooring is sloped toward the trench. In a typical plant, one four-inch 10.16cm) drainage inlet is provided for each 400 square feet (37.16 square meters) of floor space. A slope of about one-quarter inch per foot (2.08 cm per meter) to drain age in lets is generally adequate to ensure proper flow with no puddling. In dry production areas, where only a limited amount of water is discharged on to the floor, an adequate slope may be about one-eighth inch per foot (1.04 cm per meter). It is important that floors slope uniformly to drains with no low spots to collect liquid.

  • The location of floor drains depends up on many factors such as the type of task conducted in the space, the geometric shape of the area drained, truck traffic patterns, and equipment locations.
  • There are special drainage considerations in areas where there is a high volume of water usage. The water in trench drains should flow in the opposite direction of the product flow, for example, from the poultry evisceration to the picking areas.
  • All parts of floors where wet operations or where floors are to be frequently hosed down should be pitched to floor or trench drains.
  • Floor drains should not be located under equipment because it makes them in accessible cleaning.
  • Rooms without floor drains such as dry storage, large finished product coolers, and distribution warehouses may prefer to use mechanical cleaning machines instead of installing drains. Examples of such cleaning devices are floor scrubbers and dry/wet vacuum machines.

4. Trap Seals

Each floor drain should be equipped with a deep seal trap and vented properly to the outside. The purpose of such traps is to seal off the drainage system so that foul odors (sewer gases) cannot enter the plant. Effectiveness of the trap depends up on enough water remaining to constitute a seal. As water flows through the trap and down the drainpipe, suction is created that will pull the water out of the trap and break the seal unless the suction is broken by venting the drainpipe on the effluent side of the trap to the outside air. The seal can also be broken by evaporation of trapped water. This is not a problem in frequently used drains, but does occur where drains are seldom used.

5. Drainage Lines

All drainage lines must comply with local code requirements. They should be installed and maintained to be leak proof. To prevent drainage lines from becoming entrances in to the plant for pests, including rats and mice, all lines must be equipped with effective rodent screens. Secure drain covers, in addition to keeping out pests, also serve to prevent blockage of the traps and drainage lines with product scraps or other material too large to flow freely.

6. Clean outs

Clean outs should be installed in the drainage system to prevent sewer blockages. Consider the following guidelines when installing clean outs:

  • Clean outs should be located so they are readily accessible, and can be used without constituting a threat of contamination to edible products.
  • To help avoid water puddling, clean outs should be located on the ‘‘high lines’’ of floor slopes and away from traffic patterns.