Overview

Contaminated water can represent a significant health hazard to persons dealing with water damage and it is important to properly assess and monitor site conditions to minimize any adverse exposure.

Numerous factors influence the cleanliness of water, however, time is considered a key element; therefore, quick response to water damage is paramount in dealing with any situation.

The Institute of Inspection, Cleaning and Restoration Certification (IICRC) has done a tremendous amount of work towards advancing the science of water damage restoration including publishing the Standard and Reference Guide for Professional Water Damage Restoration; S500.  This document, available from IICRC, provides professionals with a procedural standard for handling water damage.

Water Categories
Most professionals have adopted IICRC's definitions of water contamination which provide three general categories:

• Category 1 (Clean Water) - Originates from a source that does not pose substantial harm to humans.  Examples include broken water supply lines, tub or sink overflows without contaminants, melting ice or snow, falling rainwater, broken toilet tanks/bowls without contaminants, etc.

• Category 2 (Gray Water) - Contains a significant level of contamination and has the potential to cause discomfort or sickness if consumed by or exposed to humans.  Examples include discharge from dishwashing or washing machines, overflows from toilet bowls with some urine (no feces), sump pump failures, seepage due to hydrostatic pressure, broken aquariums, punctured water beds, etc.

• Category 3 (Black Water) - Contains pathogenic agents and is grossly unsanitary.  Examples include sewage, toilet backflows from beyond the trap, and all flooding from seawater, surface waters, rivers, streams, etc.

Important:  The above examples of water categories are illustrative only.  In all instances, there may be unseen conditions that alter the categorization of water and make it unsafe.  For example, clean water may pick up toxins, pesticides, heavy metals, organics, etc. from contact with surfaces and immediately be transformed to a Category 3 (Black Water) quality condition.  If in doubt, consult an experienced professional.

Microbial Amplification
Thousands of microorganism types flourish in water and water damaged materials.  Over time, these organisms can multiply to a level that becomes hazardous to humans; therefore, time is a key factor in dealing with water damage.

In most cases, visible fungal growth may be expected within 24-48 hours after substrates reach sufficient moisture content.

Bacteria reproduce by binary fission (the cell divides and forms two cells, those two divide and form four, etc.) with the interval between completion of each reproductive cycle called the generation time.  In some bacteria, the generation time is short (minutes) and in others, it is quite long (hours or days).  E. coli is particularly prolific with a generation time under optimum conditions of approximately 20 minutes.

As an illustration of E. coli amplification, cells dividing every 20 minutes starting with one cell at 8:00 am could produce over a billion cells by 6:00 pm that day!

Fortunately, viruses are not able to reproduce by themselves and depend on a host organism, however, should be considered in all cases where water damage involving bodily fluids are involved or insect vector viruses may be expected (i.e. mosquito-borne).

Water Categories & Microbial Contamination
Combining the above two charts shows that as microbial amplification occurs, Category 1 (Clean) and Category 2 (Gray) waters can be transformed into Category 3 (Black) water over time.  

This aspect makes fast response to water damage an important issue, not only from the standpoint of clean-up methodologies, but also to minimize the added expense of dealing with Category 3 problems and the potential adverse heath issues.

Decontamination & Biocides
It is worthwhile to note that many products used to decontaminate water-damage are regulated in the United States under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).  

Virtually all pesticides must be registered with the U.S. EPA and a 'pest' is defined as any insect, rodent, nematode, fungus, weed, or any other form of terrestrial or aquatic plant or animal life, or virus, bacteria, or other microorganism (except viruses, bacteria, or other microorganisms on or in living man or other living animals).  

FIFRA governs the manufacture, sale and use of a wide range of chemical and biological pest controls (a few exceptions are provided for general deodorizers, bleaches, cleaning agents, etc.).  Furthermore, in Texas many such materials are under the jurisdiction of the Structural Pest Control Board and licensing is required for their use.

Links to:

EPA: Pesticides

SPCB of Texas

Summary
The proper response to water-damage is critical, not only in minimizing damage to goods and property, but also to minimize potential adverse health effects of people.

A quick response by trained and knowledgeable people should be considered in all water-damage incidents.  At a minimum, consider IICRC certified firms for all Category 3 incidents (or any incident that has the potential of becoming a Category 3).  A referral directory for IICRC certified firms is available at www.IICRC.org.