ATP Testing Helps Ensure Effectiveness of Sanitation Efforts

Adapting a technology that is used extensively in the food services industry, healthcare providers are now using adenosine triphosphate (ATP) sanitation monitoring systems to detect and measure ATP on surfaces as a method of ensuring the effectiveness of their facilities’ sanitation efforts.

“Although the food service and healthcare industries are drastically different in most respects, they share an absolutely critical need for effective sanitation. In either industry, a single lapse in sanitation can have far-reaching consequences,” says Jim Topper of Neogen Corporation, who has worked with the food industry for several years to develop ATP testing instruments and testing protocols. “We’re seeing a lot more interest in these systems from hospitals and healthcare facilities primarily because of the change in posture by some insurance companies and government reimbursement programs toward hospital-acquired infections (HAIs). These facilities are seeing the link between some HAIs and cleaning. They’re placing a renewed focus on equipping their environmental services group with a formal, measurement-based program for evaluating their cleaning effectiveness.”

Rather than detecting a single pathogen of known concern to medical facilities (e.g., Clostridium difficile), testing for ATP is used as a tool to quickly determine cleanliness—regardless of whether the ATP detected originates from benign sources or pathogens.

“Testing for ATP is not intended to replace single pathogen tests that help infection control specialists track the possible spread of especially dangerous pathogens. Monitoring for the presence of specific pathogens will always have its place,” Topper says. “For example in the food industry, companies use ATP testing as part of their daily sanitation protocol, and specific tests for E. coli O157:H7 and Listeria monocytogenes to monitor their facilities for the presence of these especially dangerous pathogens. In food production, the material comes from food and microbial matter. In a hospital, the ‘dirt’ is also organic but comes primarily from bodily fluids and hand contact. In either case, because it’s organic, if we don’t remove it from the surface, it can easily contaminate the next person who comes into contact with it.”

ATP plays an important role in cell biology as a coenzyme that facilitates intracellular energy transfer. Because ATP is present in all living cells, ATP sanitation monitoring systems detect the amount of organic matter that remains after cleaning. The amount of ATP detected, and where this ATP was detected, signals personnel of possible trouble spots that may need to be re-cleaned, and the possible need for improvement in a facility’s cleaning protocols.

“I spend a great deal of time working with cleaning professionals to help them understand what ATP sanitation monitoring systems can do for their operations, and then assisting them to implement the systems into their facilities,” Topper says. “Properly utilized, sanitation monitoring systems allow for the almost instantaneous detection and measurement of ATP on contact surfaces, which provides an objective, actionable tool for monitoring of a facility’s cleaning efforts.

Topper adds, “It’s also an excellent tool for training. I was working with an environmental services director at a hospital in California recently and we did some testing in a patient room after it had just been cleaned. We were getting pretty high numbers but in one area in particular, the bedrail console, the number was 14,500 relative light units—which is way too high. The environmental services director called in his housekeeper and explained what we were doing. The housekeeper suggested that she might have missed that area with her cleaning. The director had her clean the area again which resulted in a dramatically lower reading—500. He then explained that what she had just done was remove 14,000 germs that could have contaminated the next person to occupy that bed.”

ATP sanitation monitoring systems can be utilized with accompanying data processing software to upload testing site information and to download testing results—using this combination allows for the tracking and analysis of a facility’s testing results. The procedure starts by defining a test plan in the software. This test plan identifies all of the testing sites in a facility that could be tested and assigns pass, marginal and fail thresholds to each site. Once the test plan is defined, uploading the information to the instrument allows the user to select the appropriate site before taking each test. The result, along with the time, date, user, site name and site group, can then be downloaded to the software for tracking and analysis.

“In every facility that I visit, there is some equipment that is very easy to thoroughly sanitize, such as flat impermeable tabletops, and some equipment that is very hard to get really clean, such as bed rails and consoles,” Topper says. “By establishing a test plan for a facility, it becomes very apparent by analyzing the data what is giving a sanitation crew the most trouble. In those cases, alternative methods and materials for sanitation may be needed to provide effective cleaning and disinfecting. It’s critical that the environmental services manager and infection control practitioner work together to establish this program. The infection preventionist must look at the environmental services manager as a partner in the effort to reduce the incidence of HAIs.”

The hospital can benefit from an ATP testing system in two stages. First, they’ll have a standard by which they can measure their cleaning effectiveness as it exists with the people, processes, chemicals and equipment they have. Any cleaning that is done can be measured against this standard to see if and when the process has failed. After these standards have been established, they can then set improvement objectives and develop and share best practices to achieve those objectives. The system gives them an intelligent method by which to evaluate the effect of changes made toward reaching those objectives. They can find out very quickly whether changing a chemical, cloth or process results in an improvement in their cleaning effectiveness.

“ATP sanitation monitoring is a simple and quick tool for healthcare facilities to monitor the effectiveness of their cleaning efforts, and make adjustments where necessary. It takes the subjectivity out of the judgment call whether a facility is ‘clean’ enough, and provides a facility with objective, actionable and trackable test results,” Topper says. “At the end of the day the relationship should be that the ATP sanitation monitoring system provides a hospital or health care facility with a means by which they can achieve a cleaner facility. A cleaner facility should result in lower incidences of HAIs, happier patients and fewer headaches for infection preventionists and environmental services managers.”

How ATP Sanitation Monitoring Systems Work

ATP (adenosine triphosphate) sanitation monitoring systems have evolved into the current “gold standard” for food and beverage production facilities to monitor their sanitation efforts. The science behind the ATP systems stems from the study of fireflies. In fireflies, two chemicals, luciferin and luciferase, combine with the ATP in their cells to produce light. This reaction, referred to as bioluminescence when it’s in nature, and chemiluminscence when incorporated into a commercial product, is the basic principal of all ATP sanitation monitoring systems.

The second major element of an ATP sanitation monitoring system is the use of a luminometer to measure the light produced by the reaction of ATP with luciferin and luciferase. The luminometer contains a device, either a photo-multiplier or photo-diode, which detects the amount of light that is being produced from the chemiluminescent reaction occurring in the sampling devices.

When you rub the ATP sampler or swab across a surface, ATP is collected on the sampling tip. When you activate the device, typically by pushing the plunger through the cartridge, the ATP on the sampling tip mixes with luciferin and luciferase contained on a reagent pad or in a liquid mixture. Most ATP sanitation monitoring systems also feature a liquid buffering agent to counteract the effects of sanitizers.

Since the amount of luciferin and luciferase are fixed, the amount of light that is produced by the chemiluminescent reaction is directly proportional to the amount of ATP collected. So the correlation works like this: The dirtier the surface was when it was sampled, the more ATP is collected, and the more light is produced.

The luminometer reads the light, typically by averaging a series of readings over several seconds, and reports the reading in relative light units (RLU’s). Most often, facilities establish thresholds for pass, marginal and fail levels. These levels are typically checked by the luminometer which returns a result as pass, marginal or fail, based on the established thresholds.

Some ATP sanitation monitoring systems feature software to provide managers with a tool to analyze trends and spot potential issues. After the luminometer records the readings, the data is downloaded to a computer for storage in the software.