Drain Sanitation Delivers Peace of Mind

In most cases, biofilms can be associated with a dark or light slime on the drain surfaces. The majority of the biofilm/slime is usually formed in underground drainpipes, where cleaners and sanitizers have very limited access, making it easier for pathogenic microorganisms to reside and multiply. This means that drains that are not cleaned and sanitized properly and regularly can become a major source of microbial contamination such as Listeria, Salmonella, and Escherichia coli.

Once in drains, microorganisms can be transferred to food processing and food service areas in various ways. For example, clogged drains can sometimes cause contaminated drain water to back up from the drains into the preparation area. Blocked drains can also create positive air pressure inside the drains, which will force the air to flow back from the drains into the preparation area, dispersing microorganisms through microbial aerosolization.

Another problem occurs when drains are cleaned with brushes using an up-and-down motion—instead of a circular and side-to-side motion—and rinsed with high-pressure water. This method causes all microorganisms in the drains to splash back from the drains onto the food prep equipment and food area floors.

Therefore, it is crucial, when cleaning drains, to use the right tools, chemicals, cleaning procedures, and frequency to eliminate any microbial problems in food processing and preparation areas. Without removing the biofilm matrix, it is impossible to kill the pathogens in drains.

If possible, floor drains in food processing and preparation areas should be cleaned and sanitized daily. If not, a thorough cleaning and sanitizing once or twice a week is recommended to reduce the number of pathogenic microorganisms in the drains. This can be achieved by either of two procedures:

• cleaning drains using detergents, brushes, and sanitizers; and
• cleaning drains using PerQuat technology (Zep Inc.), a foaming hybrid of hydrogen peroxide and a quaternary ammonium compound.

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A foaming hydrogen peroxide/quat hybrid provides 360-degree coverage of pipes and can help attack biofilms.

Cleaning With Detergents, Brushes, and Sanitizers

This procedure, the most common one, starts with brushing the drains with a cleaning solution, rinsing them, and concluding with a flood sanitization using a traditional sanitizer. Although this procedure is effective, it can also be detrimental to the food safety program if sanitation workers are not properly trained. There are five critical elements to this procedure.

Brush size: The diameter of the drain brush should be at least 0.5 inch smaller than the diameter of the drain. Pulling a larger brush out of the drain will splash microbial cells back from the drains onto the food preparation surfaces.

Drain brush movements: As mentioned previously, brushing the drains with an up-and-down motion instead of circular or side-to-side motions will also cause microorganisms to splash from the drains onto food preparation surfaces, contaminating them with all sorts of microorganisms.

Rinse water pressure: Rinsing the drains with a large amount of water at low pressure is recommended to wash off all microbial contaminants and prevent them from splashing back onto the processing equipment and food contact surfaces.

Drain brush cleaning: Many workers place brushes on the floors when they are finished brushing the drains. This can contaminate the floors and surrounding area. After brushing the drains, workers should place brushes in buckets of a strong sanitizer solution and then clean and sanitize them in the cleaning area or janitorial sink. Drain brushes should be color-coded to separate them from the brushes that are used to clean food contact surfaces and equipment.

Underground drainpipes: This procedure is only effective in removing biofilm from the visible and accessible part of the drain. Unfortunately, the underground drainpipes that are not touched with brushes and sanitizers are covered with large amounts of biofilm and slime that can be transferred to the processing areas by different means.