Health Risks from Water Damage
Unfortunately in the lifespan of a building there is a good chance water damage repair can become necessary. Sewer back-ups, floods and plumbing problems can lead to water damage and the resulting risk of health-threatening molds and bacteria.Microbial mold spores are always present so controlling home moisture within a building is necessary and implementing water damage repair before the spores can grow as mold is crucial.
When there is the potential for a health risk due to exposure, precautions to protect workers need to be implemented until it has been established whether or not there is an actual hazard. Safety boots and hard hats may be required, depending on the site. Workers must wear suitable protective clothes and gear: disposable coveralls, gloves, booties, eye protection and a mask with a respirator fitted with a HEPA filter. Eye protection and/or respirators must be of such a design that will guard against tiny particles or dust from entering. Dust masks do not offer suitable protection from mold spores.
The repair of a water-damaged area must also be done under controlled conditions.
Controlled means closing off of the contaminated areas where water damage repair is required in order to contain the toxins from spreading to other parts of the building. Using exhaust systems or negative air machines, the containment is to be kept under “negative pressure”. This means clean air is directed from outside the containment area and exhausted outside or through a HEPA filter.
Any items within the containment area that can be salvaged should be covered with drop cloths or removed and properly cleaned. Site debris should be bagged and sealed then vacuumed with a HEPA vacuum and wiped down with a damp cloth before disposal as construction waste. Any equipment used at the remediation site needs to be properly cleaned before it is taken from the site.
Categories of Water Quality
Water quality is divided into three different categories: clean, gray, and black. The color of the water does not actually determine the category, the source does.
Clean water damage may not need professional remediation. It comes from potable sources so it does not immediately carry microbial hazards. Clean water can come from rainwater and melting snow, broken water lines, sink overflows, leaking pipes, steam leaks and broken toilets (not containing waste).
Gray water can have microorganisms including parasites, bacteria, viruses and fungus so it carries potential health hazards and needs to be carefully treated. Examples of gray water include: water from sump pits, overflows from toilets that contain urine, waste water from dishwashers and washing machines. More info at greywater.com.
Black water has the greatest risk to health. It is associated with floods, sewage, and broken water traps. See more info from IICRC.
Even “clean water” flooding can create the environment where mold and bacteria can proliferate. Porous building materials such as carpets. insulation and wallboard are prone to support infestation. When wet or even damp the contamination can progress exponentially so water damage repair needs to begin within a day of the exposure.
Water Damage Repair Program
Determining a course of action for repairing structural components and damaged materials depends on how much water and what category of water was involved. Other important considerations include the size of area exposed, how porous the affected materials are and how long since it has gone without remediation
The extent and methods for repair of water-damaged materials and structural components are dependent on many factors; water type (quality), amount of water intrusion (quantity), area of damage (size), material porosity and composition, and time left untreated.
A water damage repair program follows the following preliminary steps:
1. The exposed area must first undergo an evaluation for electrical, structural and bio-hazards. An inspection for gas leaks or other toxic gases needs to be included in this preliminary evaluation.
Workers remediating damage from “gray” or “black” water are required to wear protective gear such as protective suits and eyewear, rubber gloves and boots as well as respirators filtered by HEPA and organic vapour cartridges. Workers must be up-to-date with tetanus immunizations and should be clear of skin abrasions or cuts. Anyone with a suppressed immune system or respiratory issues like asthma or allergies needs to stay away from the work area.
2. Occupants need to be kept safe and moved or evacuated if necessary. The work area is to be isolated and contained, warning signs posted and barriers erected if required.
3. The source of the water needs to be identified, eliminated, repaired or contained to the extent possible.
4. Equipment and furnishings should be moved or protected against microbial growth. Air-handling and exhaust systems and components should be sealed.
5. Water needs to be removed from the area using pumps, wet-vacs, carpet cleaners, squeegees mops and/or towels.
6. Dry out salvageable materials using heaters and fans, dehumidifiers, opening windows or by running the HVAC system to exchange humid air for dry. In hot weather dehumidifiers work better than ventilating the area.
7. Repair, clean and dry HVAC and structural components.
You may also want to refer to How to Avoid Water Damage.