Cleaning & Maintenance Management Online

The Silent Cleaner

August 17, 2012

Healthcare facilities are caught in a vice of which the two jaws are a growing awareness of the detrimental effects of healthcare acquired infections (HAI) and shrinking resources to address the problem.

Fortunately, professional cleaning organizations are in a position to help. Anyone providing services to the healthcare industry should be shocked by some of the latest facts and figures.

A January 2012 report from the Healthcare Cost and Utilization Project noted that the rate of infections from the particularly serious bacteria Clostridium difficile (C. diff) doubled from 2001 to 2005.

By 2009, there were 336,600 hospitalizations that involved this bacteria, which is nearly 1 percent of all hospital stays.

One strain of C. diff developed antibiotic resistance and then evolved into a form with greater toxicity.

Most importantly, the study noted that, on average, over 80 patients die every day from this deadly microbe.

Shockingly, the experts are in near universal agreement that infection rates in hospitals from C. diff could be driven down toward zero through a proper program of handwashing and surface cleaning.

This is where cleaning professionals can step in to reduce the tragedy of illness and death from HAIs and save facilities millions of dollars in treatment costs — expenses that are now often not reimbursable through Medicaid and Medicare because they are considered to be preventable incidents.

Fortunately, there is an option that has been proven to dramatically enhance normal cleaning procedures in healthcare facilities: Ultrasonics.

Ultrasonic cleaning kills bacteria and other pathogens through physical means rather than by a chemical reaction, eliminating the need for harsh compounds and the possibility of instigating resistant organisms.

After more than two years of testing in both the United States and Great Britain, the results showed conclusively that ultrasonic cleaning equipment was capable of removing bacterial contamination from items typically used in both institutional and residential settings.

Over the course of three carefully controlled studies, it was discovered that ultrasonic machines were effective in:

  • Removing both gross contamination and microscopic bacterial pathogens that are found on items after they have been involved in a black water loss
  • Destroying bacteria that pose the greatest concern to health professionals, with a strain of methicillin-resistant Staphylococcus aureus (MRSA) chosen to serve as a surrogate for such serious strains of microbial contamination
  • Supplementing normal cleaning procedures in hospitals to significantly improve infection control without being burdensome or overly expensive. The fact that the testing progressed from cleaning in controlled environments to utilization of ultrasonic equipment in two different hospitals in England verified that the results represent a real-world application rather than just theoretical data.
It should also be noted that the field testing in the hospitals was sponsored by the National Health Service in the United Kingdom as a demonstration project that was part of the Technology Innovation Program, which focuses specifically on reducing HAIs.

The Science Of Ultrasonic Cleaning

Ultrasonic cleaners use sound waves produced at frequencies higher than our ears can perceive.

The process involves the use of a generator, called a transducer, in a water tank, which creates high-frequency sound waves.

As the sound waves move through the liquid, they create compression waves that "tear" the liquid apart, leaving behind many millions of microscopic voids or partial vacuum bubbles; the technical name for this effect is cavitation.

These small bubbles expand and eventually implode when they strike an object, and this energy dislodges contaminants even from intricately shaped surfaces.

The usefulness of ultrasonic cleaning in regards to biological pathogens such as bacteria and viruses has been known for some time.

However, until recently, most of these efforts have been limited to small equipment like clamps and dental molds.

The testing done for efficacy on large items such as wheelchairs, commodes and other common hospital items is truly groundbreaking in the ultrasonic industry.

Highlights Of The Three Tests

In all three tests, a commonsense approach was followed.

The ability of ultrasonic equipment to kill microbial contaminants was measured by collecting samples from items prior to and after being cleaned.

Immediate feedback was provided in all three studies by collecting samples on swabs that were analyzed by field equipment using adenosine triphosphate (ATP) technology.

In two of the studies, side-by-side surface samples were also analyzed by an independent laboratory to determine concentrations of specific types of bacteria.

The first independent test was conducted in order to determine if the cavitation process was as effective at removing bacteria as it was at dislodging dirt, grease and other non-hazardous materials.

A variety of residential and commercial items were tested, including toys, a wheelchair and electronic components.

The sampling data generated during the initial study revealed that bacterial reduction of nearly 100 percent — 99.86 percent and 99.98 percent, respectively — was achieved for items that were grossly contaminated.

Just as important, there was no evidence of cross-contamination even after the water in the ultrasonic tank had been used to clean items with extreme bacterial counts.

A follow-up study focused on cleaning items with the sorts of infectious agents found in hospitals.

This work had to be completed in a controlled environment since representative items were intentionally contaminated with raw sewage and live MRSA. Again, the study results showed that the process was exceptional at removing contaminants.

The two earlier studies garnered interest from the National Health Service in England, as they aggressively attack the problem of HAIs.

In this case, a three-month trial was extended to six months because of the impressive results that were obtained.

However, it is important to note that, in the hospital study, the "ultrasonic technology cleaning system was not intended to, and did not, replace standard cleaning; all equipment continued to be cleaned in the usual way."

In other words, the infection control experts understand that ultrasonic cleaning is a supplement to existing infection control efforts, not a process that supplants it.

1,025 measurements were collected from items before and after cleaning during the course of the study at the two hospitals.

A careful analysis of the data showed "an average of a 98 percent change in the reflective light unit (RLU) reading when the average pre-clean reading is compared with the average post-clean reading."

The results were so consistent and impressive that the researchers were able to draw a stronger correlation than expected.

The stated goal was to measure the cleanliness of particular items with the expectation that better cleaning would, indeed, have a positive effect on the number of HAIs.

At the conclusion of the trial period, the study authors noted, "The evaluation was not designed to assess the effectiveness of ultrasonics in reducing infection, but it was more effective than normal routine cleaning."

At the conclusion of the study, hospital personnel had some specific recommendations and conclusions.

They noted that the ultrasonic cleaning was especially useful for wheelchairs, tables, toys, chairs, intravenous (IV) stands and more.

Implications For The Cleaning Industry

As healthcare organizations struggle for increasingly scarce dollars, their attention is quickly turning toward minimizing HAIs.

Cleaning contractors are in a prime position to assist such organizations in a variety of ways.

Ultrasonic cleaning of items that are known to spread infections can be offered in several fashions.

Using a mobile unit mounted in a trailer or a van with contracts for specialized cleaning of large hospital items on a weekly or monthly basis using ultrasonic technology is one potential business approach.

Another option would be to work with the facility to put a machine on site so that a larger number of items could be cleaned frequently.

Regardless of the specific approach, integrating ultrasonic cleaning into the range of services provided to healthcare facilities is one of the keys to reducing HAIs and limiting the personal suffering and financial loss that comes from these preventable diseases.


Michael Pinto, Certified Safety Professional (CSP), Certified Mold Professional (CMP), is chief executive officer (CEO) of Wonder Makers Environmental Inc. He focuses on commonsense practices that work when health professionals are faced with threats from swine or avian flu, MRSA outbreaks, norovirus exposures and nosocomial infection problems in healthcare facilities. Pinto is the author of over 150 published articles and several books, including Fungal Contamination: A Comprehensive Guide for Remediation. Pinto can be reached at (269) 382-4154 or MAP@WonderMakers.com.