Mold and trapped moisture: Dry with care

Whenever the structural components of a building are subject to abnormally high moisture conditions, the probability of mold growth is high. According to Ernie Storrer, owner of Bales Restoration and president of Injectidry Systems, Redmond, WA, only a few conditions are needed for mold or other unwanted biological activity to occur: — Presence of mold spores

• Moisture (relative humidity adjacent to surface above 70 percent)
• Temperature range: 40° F to 100° F
• Food source (virtually anything organic)
  

By controlling humidity, other parts of the structure, including undamaged building and contents, will not gain enough excess moisture to cause problems.

For remediation purposes, evaluation of the building should be undertaken as soon as possible. If structural material is not salvageable, no extra efforts should be undertaken to dehumidify it. Reasons to not salvage could include the following:

• Pre-existing mold
• Distorted so as to preclude repair
• Cheaper to replace than repair
• Customer’s wishes and preferences

If mold exists, extreme care should be exercised to minimize the chance of spreading contamination. Demolition should be accomplished with negative air pressure to prevent airborne spread of spores.

If you are not going to salvage the wet structure, remove it as soon as possible. Wet structure that needs to be removed can contribute to the total effort needed to dehumidify. By removing the wet material, the appropriate size and number of dehumidifiers needed for drying only salvageable material will be less, which reduces the overall cost to the customer and the insurer.

Remember that while you are not responsible for the initial water damage or any mold growth you find at the inception of the job, you are responsible for recommending appropriate remediation steps needed to stabilize the situation as quickly as economically possible.

Also, be careful when introducing agents to neutralize the mold. Many industrial hygienists are specifying only HEPA vacuuming of mold— no bleach and no antimicrobials.

A suggestion would be to inform the customer if you determine antimicrobials are needed. Provide them with material safety data sheets (MSDS), and explain the advantages of retarding mold growth. These problems may not be about mold but about the products that you introduce into the environment.

If the customer declines the treatment, have them sign a release. If the customer elects to have an antimicrobial applied, get them to sign a consent form that indicates their permission along with an acknowledgment of receipt of an MSDS.

The area of greatest problems after water damage is that of trapped moisture in walls and ceilings and beneath cabinets. Too often the structural components in these areas are not properly measured for moisture content, let alone dried properly. If moisture is hidden behind enameled or wallpapered walls, be sure you move dry air into these areas.

The basic rules

To summarize, the basic rules of mold remediation are fairly simple:

• Protect your people from toxic mold and its off-gassing.
• Protect and caution your customer.
• Remove the mold and noncleanable, contaminated structure.
• Avoid spreading any of the contamination.
• Control the humidity (this makes the environment less hospitable to mold).
• Do not do mold testing yourself to prove the absence of mold unless you have the credentials to do so.
• Inform but do not frighten customers. The last thing you want to do is cause a problem where none exist. Inform without scare tactics.
• Charge a premium for your work. Mold remediation done properly will cost more.

Remember that mold can and will grow even where you cannot see it. Measure, dry and measure again.