Water SafeIs your water
quality suitable for building cleaning?
By Rick Martens
The water quality at your facility greatly affects your ability to provide clean
buildings. If you're
aware of water's properties and the way these properties affect the cleaning process, your
water
can be an asset to your facility rather than a liability.
Buildings obtain their water from a variety of sources. Different sources can provide
significantly
different qualities of water.
Variables such as water hardness, alkalinity, total dissolved solids (TDS) and supply
source all
affect your staff's ability to clean a floor or carpet. Understanding your water's quality
and the
impact it can have on your buildings can help you optimize the performance of your
cleaning/maintenance staff and the products they are using.
Check Your Source Water
Water quality varies greatly depending on the source. As precipitation lands on different
areas, it
dissolves and begins to carry with it a variety of materials which alter its quality. When
water
eventually finds its way to lakes, streams or ground water reservoirs, these dissolved
substances
become a part of our water supply sources.
Every cleaning/maintenance manager should be aware of the sources of their water supply
and be
familiar with the quality of the water they use. Those who receive their water from large
lakes or
reservoirs can usually count on fairly consistent water quality.
However, buildings with a municipal supply that is drawn from several wells in different
areas can see significant changes in water quality. Even those whose source is a single
municipal or private well may see seasonal or periodic variations in water quality.
Hard Water's Problems
Hard water is the most common and significant component of water quality. It contains
water-soluble minerals that impede the cleaning process.
Though the calcium, magnesium and other minerals that cause hardness are water-soluble,
they
prefer to combine with other materials such as soaps and some detergent ingredients. This
causes the detergents to precipitate out of solution. Water hardness steals the cleaning
power
your operation paid for, requiring you to increase detergent use and therefore increase
your costs.
Water hardness can, however, be removed. A water softener removes calcium and magnesium
and replaces them with a more soluble substance, sodium.
If your water contains over 3 grains per gallon (gpg) of hardness, the water softening
system will
usually pay for itself by enabling you to reduce your detergent costs. Water with zero gpg
is
recommended for optimal cleaning performance.
Although other minerals such as iron, manganese and trace minerals can also cause
hardness,
they are more likely to cause staining problems than affect detergent consumption.
pH, Alkalinity
Other chemical properties of water quality that are significant to cleaning professionals
are the pH and alkalinity or acidity of the water.
If your source water is low in pH, the water's acidity can neutralize the cleaning power
of some of your alkaline detergents. In such cases, cleaning workers may have to use
detergents at stronger dilutions to achieve the same performance as those with neutral or
more alkaline water sources.
On the other hand, those who use low-pH detergents and have highly alkaline water (high
pH)
may have to use these products in stronger solutions than cleaning operations with less
alkaline
water.
TDS and Spotting
The sum of all the dissolved solid material in the water is called total dissolved solids,
or TDS,
and is generally measured in parts per million (ppm) or milligrams per liter (mg/L). An
extremely
high TDS can affect cleaning regardless of the type of dissolved materials.
The effect of a high TDS is different from that of water hardness. Where hardness actually
removes detergent ingredients, TDS is more of an interference to detergents' operation. As
an
analogy, consider how you would walk across an empty room, as opposed to a room filled
with
people. In either case, you can cross the room, but it will take you longer if there are a
lot of
people (interference) to slow you down.
It is difficult to say at what level TDS becomes a problem. Where detergent performance in
critical, a cleaning operation would usually get better performance using water with zero
TDS, but some operations may be able to clean effectively with TDS levels over 500 ppm.
The problem most commonly associated with TDS is spotting. Any solids that are in the last
water to touch the surface of the object being cleaned will still be there when the water
evaporates. These remaining solids will leave spots. The higher the TDS, the worse the
spotting.
Spot-Free?
"Spot-free" water can be produced by the installation of distillation,
deionization or reverse
osmosis water treatment systems at your facility.
Because distillation doesn't produce water quickly enough for large-scale applications,
facility
managers may opt for either deionization or reverse osmosis systems. Suppliers,
manufacturers
or water treatment dealers can help determine which system is right for you.
Deionization is efficient and cost-effective, but requires handling some hazardous
chemicals to
regenerate the ion exchange media. Reverse osmosis is economical and doesn't require
chemicals, but is slower than deionization and requires an additional holding tank to
store
processed water.
Like any other aspect of your operation, information and understanding are the key to
getting
optimal performance from your facility's water. If you obtain water from a municipal
source, it can usually supply you with a complete water analysis report. If you have a
private well, there are many public and private laboratories that can run a few standard
tests to help evaluate your water quality situation.
Finally, make sure that you work with your equipment and chemical suppliers to help you
better
understand your water quality. This will help ensure that you achieve maximum performance
from your cleaning equipment and products, which should ultimately lead to cleaner
buildings and happier customers.
Rick Martens is a chemist with Cleaning Systems, Inc., Green Bay, WI. This article was
adapted from an article that originally appeared in Professional Carwashing and Detailing
magazine.
Copyright© 1995 National Trade Publications, Inc.
Click Here To Go To CleanFax Online For More Articles Like This One
