Twenty or more years ago, cleaning contractors would respond to a request to deep-clean discolored grout and tile in a client’s restrooms with considerable concern and anxiety.
The concern was because there were few effective products available; grout cleaning involved strong and possibly harmful cleaning chemicals and poorly designed scrub brushes.
Also, the task was tedious and required lots of “elbow grease.”
The anxiety was because the outcome could not always be predicted.
In some cases, the results were satisfactory and the tile and grout were noticeably cleaner, which is the traditional goal of cleaning.
However, in other cases, the soil and contaminants were so embedded that little improvement was visible.
Back to the present
Fortunately, today there are several cleaning chemicals and products — from more functionally designed scrub brushes to specialized equipment — that have made the job of tile and grout cleaning considerably easier, and they often produce much better results, at least in appearance, than previously possible.
However, the standards for cleaning are higher now, and looks, though important, are no longer the most important outcome of cleaning.
We have now entered an era of scientific cleaning, which may likely have a greater impact on the professional cleaning industry — especially when it comes to performing surface cleaning tasks, such as grout and tile cleaning — than any trend that has come before it.
We call it scientific because the results of cleaning tasks are now being studied and quantified using scientific tools and equipment.
Instead of standing back and just observing the appearance of a recently cleaned grout and tile surface to determine cleaning effectiveness, we are measuring the results of cleaning using new technologies and monitoring systems.
The result is that we can analyze how well products or cleaning systems work, which can help managers select the tools that will not only make tile and grout look better, but are also more healthy and sanitary.
Studies indicate that as much as 50 percent of coliform bacteria, commonly used as a bacteria indicator to determine the sanitation of different surfaces, that is present in a public restroom is on the tile and grout areas directly around toilets, including floors, partitions and walls, and another 20 percent is in and around urinals, according to Dr. Jay Glasel, managing member and founder of Global Scientific Consulting and a professor emeritus in the Department of Microbial, Molecular and Structural Biology at the University of Connecticut Medical/Dental School in Farmington, CT.
One of the key ways coliform spreads is by toilets or urinals being flushed.
Each time the fixtures are flushed, they release aerosolized droplets often containing fecal matter, urine and other forms of bacteria into the air, which land on surrounding toilets, urinals and other surfaces.
The bacteria can then take on a life of their own and spread to other areas of the restroom and facility.
One way this occurs is by restroom users “walking” aerosolized droplets deposited on floor areas into other parts of the facility, says Glasel.
Also, if contaminated walls and other surfaces are touched by a user who does not adequately wash his or her hands, then this can be the start of cross-contamination problems.
By bringing science into cleaning, cleaners can now see if there is microbial contamination present after cleaning to help determine how effectively the area was sanitized.
However, Glasel believes we still face serious challenges when it comes to cleaning tile and grout because of two fundamental factors:
- Grout is often softer and more porous than tile, although tile can be porous as well and the grout line surface is often lower than the surface of the tiles, making these areas hard to clean.
- Restroom floors with small tiles, commonly found in modern buildings, result in high ratios of grouting surface to tile surface.
Essentially, there is more porous grout found in today’s restrooms, which means more areas are susceptible to contamination, increasing the need to successfully remove greater amounts of microbial contaminants from restroom floors.
And, Glasel says, studies confirm these trends.
According to a 1990 study of bacterial retention in tile and grout areas, the greater the degree of surface “irregularities,” grout as an example, the greater the chance of bacterial retention.
Testing cleaning methods
The most common methods used to clean tile and grout on restroom floors are string mops, microfiber flat mops and high flow fluid extraction (HFFE), which is also known as spray-and-vac or no-touch cleaning (NTC).
One way to determine the effectiveness of these cleaning methods is by evaluating the amount of creatinine (Crn) left on a restroom floor after cleaning.
Crn is excreted in urine and testing for its presence with commercially available Crn-detection kits on tile and grout areas is a means of quantifying cleaning effectiveness.
In one study, different tile and grout cleaning methods were evaluated using the following testing protocol:
- A tile and grout restroom floor was sectioned off into three different test areas of identical size. Each test area was equally soiled with fresh urine misted over the floor and allowed to dry.
- The test areas were then each cleaned with one of the three different cleaning systems. Fresh, never-used string mops and microfiber mops were used to clean two of the designated areas. These sections were mopped twice, once in one direction and then the second pass in the opposite direction. For the HFFE cleaning method, a no-touch cleaning machine was used.
- All the tests were conducted using plain water or with cleaning chemical solutions following manufacturers’ dilution and dwell time recommendations.
- After cleaning, the Crn concentration on the surface of the tiles and in all four directions of the grout lines was measured and then recorded. All measurements were repeated in quadruplicate and then statistically analyzed.
Prior to the cleaning, all of the tile and grout test sites had Crn concentrations of 50 milligrams.
After cleaning with plain water, the cleaning effectiveness of the different cleaning methods was determined.
When a conventional string mop was used, the grout area data indicated that approximately 38 percent of the Crn had been removed.
When a microfiber flat mop was used, it was also reported that 38 percent of the Crn had been removed from the grout areas.
The HFFE machine removed 98 percent of the Crn from the grout areas.
In addition, the data indicated that the string and microfiber flat mops were more effective at cleaning the tile surfaces than the grout areas.
The data indicated a 76 percent (string) and 74 percent (flat) cleaning efficiency.
However, the HFFE system demonstrated a 98 percent cleaning efficiency on the tile surfaces as well.
Glasel says the primary goal of this test was to see which cleaning method was most effective at removing Crn, which can be used to measure cleaning effectiveness.
But, because the results were so significantly different between the mops and the HFFE system, the secondary goal was to discover why.
First, Glasel believes the string and flat mops have difficulty making sufficient contact with the grout surfaces because those surfaces are usually slightly lower than the tile surface.
Second, the grout lines have a rougher surface and more surface irregularities than the smoother tiles, allowing soil to become trapped and difficult to remove.
Finally, because the tiles are also porous, soils can become deeply embedded, which also poses a challenge to remove.
This is an example of applying science to cleaning.
The purpose of the testing was not to evaluate the appearance of the floor areas after cleaning, but to see which method best eliminated potential contamination.
Using these new scientific testing methods, cleaners can ensure that they are providing effective cleaning for their clients and, in doing so, helping protect building occupant health.
Cleaning for health is the industry’s duty, and relying on science will help accomplish this.
Angelo Poneris has been in the JanSan industry for more than 10 years. He is currently the office manager for Valley Janitor Supply, a 20-plus-year-old distributorship located in Hamilton, OH.