Dry Cleaning Step by Step

When we think of dry cleaning for the food industry, we generally relate it to those food plants that have dry processing. But dry cleaning and sanitation can be a valuable option in any processing plant and can used virtually anywhere—from the environment to equipment to tools. It can be as simple as surface cleaning with a vacuum or alcohol-based wipes, or as in-depth as steam cleaning or dry-ice blasting of disassembled equipment. But no matter which is used, it is essential to ensure the products are EPA-approved for food areas and/or food-contact surfaces, depending on how the product is used, and that the cleaning and sanitation processes are verified and validated.

“People are using a lot of creative methods to clean equipment,” said Sterilex Director of Business Development Alex Josowitz. “But whatever method a plant uses, whatever you’re trying to eliminate, it needs to be validated.”

Dry cleaning can be very important for several reasons, said Pure Bioscience Executive Vice President Tom Myers. Bacteria need a food source and water to reproduce, with the controllable variable being water. “Even when you think you have dried the plant there is water in harborage areas (floor seams, machinery corners, etc.) where bacteria can be hard to remove and, with the water source …. grow,” he said.

Additionally, said Biomist Vice President Robert Cook, “Once you bring water into any area, how do you keep it from proliferating into other parts of the plant?”

As such, said Best Sanitizers National Account Manager April Zeman, “The first thing to emphasize is to review processes and employee access to ensure that dry areas stay dry. Do not introduce any moisture that is not able to quickly be removed and dried. When moisture is introduced into a dry system, pathogens can harbor.”
 

Dry Cleaning and Sanitizing Step-by-Step

Following is a guide to the steps of dry cleaning and sanitizing, based on the general flow of Biomist’s “7 Steps of Dry Cleaning” and supplemented with detail from Biomist, Best Sanitizer, Sterilex, and Pure Bioscience. While all steps won’t be specifically applicable in all plants, this step-by-step approach provides a general method which each plant can customize to its own specifications.
 

Pre-Cleaning

1. Assemble all cleaning and sanitizing tools and general and specialty chemicals.

2. Ensure footwear is clean and dry before sanitizing. Footwear sanitizing systems using an alcohol-based, EPA-approved surface sanitizer provide an alternative to foamers or mats, which are inherently wet.

3. Purge all systems and lock-out/tag-out equipment.

4. Remove guards, and release belt tension from conveyors.

5. Disassemble equipment to make all parts accessible for cleaning and sanitizing.

6. Place all removable parts, as well as loose utensils and tools, on a designated cart.

7. Transport these loose items to a separate cleaning area.

8. Soak parts in cleaning solution at proper dilution (per label instructions); ensure that extrusion nozzles are free of buildup and debris. Or place loose parts on a wire rack and spray with cleaner; allow to sit for desired time and rinse. In either case, ensure that no parts, utensils, gaskets, and tools are nested.

9. Remove debris from transport cart and/or wire rack; spray with cleaner; allow to sit for desired time, then rinse.

10. Once cleaned, place loose parts upside down to dry and to ensure all water is emptied.

11. Conduct any necessary wet cleaning first and then, when areas are dry, conduct dry cleaning.
 

Dry Cleaning

1. Depending on the soil, there may be a need for agitation or physical removal of the soil. Use either manual or mechanical action (sweeping with hand brooms, scraping, brushing, mopping, vacuuming, blowing of compressed air, etc.) to remove excess debris and organic matter. Vacuuming also contains collected dust rather than pushing it into other areas.

2. Use a systemic approach of top-down cleaning—beginning at the ceiling and working toward the floor.

3. For stationary equipment: Use a vacuum or high-pressure air to remove loose dust and dirt (if air blow-down is used ensure containment of the dust); then use pads, brushes, and dry lint-free towels with a cleaning solution (ensuring that the pads and brushes are free of dripping moisture) to hand-wipe the equipment. Use lint-free towels to completely dry all surfaces.

4. Alcohol-based, fast-drying wipes can be used for surface cleaning. If steam cleaning with a gas, cordon off the room being cleaned.

5. Once surfaces are wiped down, clean all framework, and identify and spot-clean problem areas.

6. Ensure that all surfaces and equipment are cleaned, as well as floors, walls, and corners.

7. Empty and clean all trash bins. Take particular care with the dust in the vacuum and the soiled pads and towels and properly dispose outside the plant.

8. Perform a post-cleaning visual inspection, and correct any deficiencies.

9. After ensuring all loose parts are dry, return them to their proper areas, reassemble equipment, and remove lock-out/tag-out.

10. If there is any concern that there are areas of equipment that are not completely dry, air and/or heat guns can be used.
 

Dry Sanitizing

1. Follow cleaning process by sanitizing with a dry disinfectant.

2. Use a low-moisture, EPA-registered sanitizer which is safe for food-contact surfaces, such as alcohol-based formulas, as alcohol is highly effective and evaporative, dries quickly, and requires no rinsing.

3. Sanitizers may be in the form of ready-to-use, alcohol-based wipes, sprays, or mists.

4. An alcohol/quaternary ammonium sanitizer can be used almost anywhere as a final kill step. While leaving a safe antimicrobial residual, the evaporative qualities of the compound enable surfaces to be dry and ready for processing within minutes.

5. When evaluating chemicals, check that the selected sanitizer is an EPA-registered surface sanitizer for food-contact surfaces and that it doesn’t require a rinse.

6. After sanitizing, conduct a visual inspection, validate and verify sanitation. Correct any deficiencies.

7. Document cleaning and sanitizing, as well as any corrective actions. Release for production.
 

Ongoing

1. Hand hygiene, glove, and footwear sanitation provide a crucial role in plant sanitation so as to minimize cross-contamination from employees. Handwashing, hand-sanitizing, and footwear-sanitizing systems should be set up in processing area entryways.

2. A key source of contamination in the plant is the entryway to the processing area. Boot dips and foams are common, and a dry formulation can provide a barrier in areas where wet chemicals cannot be used. Be sure that the product being used is an EPA-registered sanitizer, not just a cleaner.

3. Training and employee culture are also key. There should be consistent company-wide training and enforcement of hygiene and sanitation procedures. It should be performed as if an auditor is always present. For example, if the regular crew knows the procedures, but there is no training program for temporary workers, then the effectiveness is reduced.

4. The same can be said for maintenance. If production has a procedure for dry cleaning and sanitation, and then maintenance comes in and moves machinery, dry cleaning and sanitation should be completed again.

5. Document. Particularly in today’s world of FSMA, if it isn’t documented, it didn’t happen.

The author is Editor of QA magazine. She can be reached at llupo@gie.net.