Mold Remediation - Alison Service Co

Mold. It’s wet, it stinks, and it is an expert in guerilla warfare.There are over 100,000 species of mold (~1,000 in the U.S.) which can be found most anywhere, both indoors and outdoors. In addition, molds wil present themselves in many forms, colors and species while also posing numerous dangers. Mold can be difficult to pinpoint and correct without creating additional issues. The aim of this article is to provide enough general information to aid in decision making when facing mold. Before generating a strategy, we must first understand more about mold and its risks.

What is mold?

An organism in the fungi kingdom, mold is organized into three groups according to human responses:

Allergenic — unlikely to cause illness, though it may aggravate mild allergies
Pathogenic — can cause infection in people who are immunocompromised
Toxigenic — produces and contains toxins harmful to all humans and animals.

Hazardous species commonly seen in commercial remediations are the toxigenic Stachybotrys and the pathogenic Aspergillus.

Exposure Symptoms

Symptoms vary, but may include allergic reactions, skin rashes, sinus inflammation, fever, aggravation of asthma, chest tightness, headache, lightheadedness and mental fatigue. With repeated inhalation of mycotoxin spores, some people can develop chronic inflammatory response syndrome (CIRS).

Growth

Moisture is the enemy, and unmitigated moisture will undoubtedly perpetuate mold growth. Therefore, moisture control is the most important strategy. A single mold spore only requires moisture, oxygen and virtually any organic matter to begin its growth process. This process can occur in as little as 24 hours. Any damp or wet building materials should be quickly dried out in 24–48 hours. The interior relative humidity (RH) should be no more than 60%. Any RH above 70% for extended periods of time will promote growth. To reduce RH, either increase ventilation if outside air is dry, or dehumidify if outside air is humid.

How to Identify

Stachybotrys, also known as “black mold,” is typically black but can also be different colors such as dark green, grey or brown. Not all mold that is black is “black mold.” The term black mold is only referring to the specific species of Stachybotrys. Since Stachybotrys usually grows in dark, hidden places, the first signs will typically be a musty odor. Aspergillus, on the other hand, is typically seen on the surface of walls, ceilings, subfloors or crawl spaces. Aspergillus wil be black on the surface and usually white/yellow underneath. Contracting a lab for testing is not always necessary. However, testing may be required when a medical diagnosis is consistent with mold symptoms or required to determine the outer boundaries of severely contaminated areas before, during and after a remediation. A few of the common tests are air sampling, surface testing and bulk sample testing.

Failures and Sources

Possible moisture sources to identify include failed flooring, grout that allows water to seep into walls, plumbing, walls or slabs that are wicking moisture, failed roofing/flashings/drains, windows, pipes sweating, drain pans, irrigation and spores in the HVAC system. During HVAC PM, technicians should check damp filters, overall cleanliness, drain pans, coils, cooling towers, etc. Reports of standing water, inside or outside, should be addressed. Janitorial crews using excess water during cleaning can also severely exacerbate the interior RH and any existing failures.

Dangers

Although mold is mostly inert, it should be handled with caution and remediated. However, if undisturbed, a current situation will not immediately worsen. Unwanted disruption is a major concern and will generally occur due to inexperience with mold. Nothing should be touched without proper planning, equipment and PPE. Doing so will inevitably jeopardize the entire remediation campaign. An uncontained release can cause surface contamination and potential inhalation by, and contamination of, the HVAC system. Moreover, if left unchecked, mold can damage building materials, finishes and even structural components. A non-physical danger of mold is personnel openly saying the words “mold,” “black mold” or “toxic mold.” The simple utterance of these words alone has been enough for claims to be filed, warranted or not. It is critical that information and findings are reported directly to the correct personnel to determine the next steps.

Common Monitoring Equipment

Hydrometer — for measuring the interior RH (acceptable range: < 60%)
Moisture meter — for measuring building materials (acceptable range: < 15%)
Thermal imaging camera — for visual of cold/damp areas
Dehumidifier — for removing moisture vapor from the air (drain required)
Air scrubber/purifier — for removing particulates such as spores and allergens (HEPA filter required)

“There are over 100,000 species of mold [~7,000 in the U.S.] which can be found most anywhere, both indoors and outdoors. In addition, molds will present themselves in many forms, colors and species while also posing numerous dangers.”

PPE and Sanitizing

Full-body Tyvek suits, latex gloves and NIOSH-approved (National Institute of Occupational Safety and Health), full-face respirators are required for remediation work. A standard dust mask is not acceptable. The minimum allowable facemask type for such work is N95 or greater. When using a facemask, goggles must be fully sealed and without vents. Painting over mold is not a recommended resolution. Products can be purchased from local hardware stores to neutralize mold, such as Concrobium. Note: Never mix bleach and ammonia products. Neutralizing should be completed by a janitorial, maintenance or HAZMAT vendor.

Remediation Key Points

If mold covers more than 10 square feet, consult a HAZMAT demolition specialist to determine local licensing and/or HAZMAT certificate requirements. This varies from state to state, but this discussion is a great starting point. In general:

Control the moisture, and repair failures.
Determine if testing is required.
Shut down the HVAC system and cover vents/returns to stop air flow during the remediation process.
Limit power tool use to keep dust down.
Fully seal the work area and isolate from the rest of the facility, along with additional coverage of all contact surfaces and equipment.
Use a dry, step disinfectant sanitizer to clean footwear (non-liquid due to slip risk).
Put affected building materials directly into a double-lined trash bag.
Use HEPA-filtered air scrubbers and dehumidifying equipment.
Sanitize contact surfaces throughout the process.

Mold is an elusive opponent. Its many forms, potential risks and varied symptoms may be difficult to understand. However, with remediation of any size, health and safety is the main priority.