Zone Assessment for Effective Environmental Monitoring

Zone Assessment for Effective Environmental Monitoring

Food safety managers face a dilemma: limited budget with an expectation (both from executives and the consumers) to build and maintain a bullet-proof food safety program. All too often, we see managers go through a full list of sampling sites in order over and over again. Although it is a good way to confirm that all sites have been covered, it is not the best way to utilize scarce resources. With Presage, managers can prioritize sampling sites so those with higher priority are tested more often than the areas with lower priority, while at the same time making sure that all areas were tested within a specified period.

Zone Assessment

An important step in building a bullet-proof food safety program is conducting a zone assessment of the entire facility. All production areas, storage, receiving, loading docks, and other areas employees may visit during their working hours must be surveyed, paying close attention to areas with high potential for re-contamination.

Presage has a powerful location organization system which labels each site three ways: by process zone, product proximity, and severity. Process zones are areas in the facility such as receiving, packaging, chilling, or conveyor lines. Proximities may be food contact, non-product contact, environmental and non-production: you may have heard of it as the zone concept. Severities identify the level of risk in contamination: high, medium, low.

Following is a screenshot from Presage showing how sampling sites are organized.


Every production facility is designed with the flow of process steps in mind. Grouping sites by zones helps technicians find sampling sites quicker, and it helps managers monitor the trends for each process zone over time.


Food contact surfaces are areas that come into direct contact with the product before the product is sealed in the primary package. Examples include conveyor belts, utensils, slicers, bins, chutes, fillers, etc.

Non-product contact areas are closely adjacent to the product contact surfaces. For example: equipment framework, drip shields, overhead pipes, computer screens, maintenance tools, etc.

Environmental areas are in product processing areas, but not closely adjacent to food contact surfaces, like floors, walls, ceilings, drains, hoses, trash containers, brooms, drip pans, foot baths, etc.

And non-production areas are remote from product processing areas. These are hallways, loading docks, bathrooms, locker room, cafeteria, etc.

Usually, environmental and non-production areas are prone to re-contamination. Although they do not need to be tested as often as product contact and non-product contact areas, the importance of testing environmental and non-production areas should not be underestimated.


In Presage, severity is assigned to each process zone and product proximity combination. For example, food contact surfaces in the ready to eat processing areas of the production plant will have a high severity.

Note: All zone, proximity and severity names are customized to each plant in Presage.


Now, using the process zone, product proximity, and severity of each sampling site, managers can plan their schedule. Frequency of sampling can be based on any one of the three groupings: product contact surfaces may be tested more frequently than non-product contact, or process zone 1 may be tested on a daily basis while process zone 2 is tested on a weekly basis, or more high-severity sites are tested than medium-severity on a daily basis. These preferences can be set initially and easily modified.

Food safety managers have it rough, with scarce resources they are expected to design a top-notch food safety program. Presage makes it easy! Set priorities to sampling sites, and make every sample count. This is how we make food safety compliance simple.