To many housekeeping employees, cleaning is a series of tasks they’ve learned to perform over the course of a shift – trash removal, dusting, vacuuming or mopping. These tasks, and many more, essentially are done to make their areas look presentable and reduce customer complaints.
However, workers also should look at cleaning from the perspective of all that it does for the environment in which they are working. Every housekeeping employee should understand that cleaning actually is the process of locating, identifying, containing, removing and properly disposing of unwanted substances from an environment. A clean environment can be an object as simple as a floor or shelf, or a structure as complex as a school or a 10-storey office building.
Providing the workers with the right chemicals and tools, as well as teaching them how to use these products, is not enough. They must also understand the purpose and the science behind their actions. Without this knowledge, workers could misuse products, causing more harm than good to indoor environment. First, employees need to understand how the solution affects what they are trying to clean from a surface.
Cleaning solutions are either a mixture of water containing soaps or detergents, or an organic solvent in liquid or gaseous form. Polluting substances differ widely in their tendency to dissolve in various solutions, but a common assumption is that likes dissolve likes.
In cleaning, it’s always important to understand the process of how things dissolve and become suspended before they become removable. The hydrocarbon tails of the soap ions dissolve in the hydrocarbons of an item soiling a surface. This reaction then gradually breaks apart the soil as the charged, water-loving, head of the ion is drawn toward surrounding water molecules. The attractive forces of the water molecules and the head of the long hydrocarbon chain literally pull the soil apart.
As the breakage occurs, bits of unwanted substance are held in suspension by the soap solution. Because the charged heads of the soap ions are the same charge, they repulse each other, thereby keeping the soil from reforming. Wash water then emulsifies and carries away the soil.
Removing pollutants from a surface often requires the help of mechanical action such as scrubbing with a brush. Workers always have to use some degree of agitation and mechanical force because the agitation makes the molecules of the cleaning solvent interact faster with the molecules of the substance being dissolved.
Agitation also helps particles separate by providing the initial momentum for the charged particles to separate and then rearrange themselves according to electrostatic charges. So, for instance, simply pouring toilet cleaner into a bowl and flushing after a few minutes will not remove bacteria as well as agitating that solution with a brush can.
The elements that aid cleaning
Like water, air is a fluid and equally important in the cleaning process. As air flows, it carries suspended materials – gases and small-suspended particles called aerosols – with it.
Airflow is also necessary to achieve drying. Many times, tasks such as carpet extraction could do more harm than good because employees don’t fully understand what is involved in thoroughly drying a surface. Drying occurs only when suspended moist air is displaced by dry air on, above and through an environment that has been cleaned. Many cleaning problems occur when environments do not dry, creating breeding grounds for potentially harmful organisms. A classic example is over-wetting a fabric, then not drying it adequately, which creates an opportunity for mold to grow.
Time is another critical element. If workers must capture dirt or microorganisms in a solution that then breaks them down for removal, all those steps obviously take time. Applying a solvent to break down oil and then wiping it off right away, will not allow ample time for a chemical reaction to take place. In trying to increase productivity, workers may wipe off chemicals before they can take effect, leaving behind the microorganisms they’re supposed to remove. This can lead to cleaning that area more often, due to a building up of microorganisms.
Temperature also is an important element in cleaning, especially as it affects the solvents that break down pollutants. Dirt dissolves much faster in boiling water than in ice water. Elevated temperatures, therefore, can make cleaning more efficient and allow workers to use less chemical to dissolve a given amount of substance.
Heat also destroys living organisms, though critical times and temperatures vary, depending on how well each organism resists heat. This is important when workers must disinfect surfaces – cold water could void a disinfecting task. The last two steps: removal and disposal, are critical. The more pollutants workers remove, the more effective their cleaning becomes, and the better their actions protect occupant health.
Simply removing pollutants does not make cleaning effective. Cleaners must dispose of unwanted materials properly to truly improve the indoor environment. Disposal must be logical, legal, socially acceptable, environmentally suitable and in accord with cultural tradition.
Cleaning buildings may not seem like rocket science, but it is a highly scientifically-based exercise.
Dr Michael Berry
