Mold is usually secondary damage caused by ineffective water damage mitigation. Any time that mold is discovered in a structure, it should be removed. It will not go away or get better on its own. The mold has to be removed and the area where it was growing properly treated to make sure it does not return.
Of course any time that mold is disturbed, it releases thousands of microscopic mold spores into the air, spores that, if inhaled, can cause various types of health issues, from allergic reactions such as runny nose, watery eyes, and skin irritation, to more serious issues such as neurological disorders or even lung disease.
There are two types of control measures to prevent mold exposure to workers, engineering controls and Personal Protective Equipment (PPE). Engineering controls are best because they drastically reduce the chance of exposure without (or in addition toPPE). Some examples of engineering controls include controlled demolition which is the removal of affected materials in a controlled way, mold containment as well as controlling air movement with the use of AFDs (air filtration devises). Engineering controls reduce the amount of mold spores and mold fragments that become airborne and reduce the amount of time they remain in the air, thus reducing worker exposure.
Mold containment is created by erecting chambers using 6 mil fire retardant polyethylene sheeting, used to separate areas of mold contamination from other unaffected areas of the home or building. Containment can be built in a few ways by using (apart from the polyethylene sheeting) pieces of wood or poles as support, tape and zippers. The contained area must be kept under a state of negative pressure relevant to the other rooms in order to help prevent contaminated air from spreading to previously unaffected areas of the home.
PPE is an IICRC certified must for all mold remediation professionals. PPE is designed to protect the worker from exposure to mold spores. Gloves, preferably long ones, are required to protect the skin from contact with mold allergens, or worse, toxins, such as those found in black mold. They also protect from potential irritation from cleaning solutions. The gloves should be made from a heavy duty material such as neoprene, nitrile, polyurethane, or PVC.
Eye protection is also required when dealing with mold. Use properly fitted goggles or a full face respirator with High Efficiency Particulate Air (HEPA) filter. The eyes provide one of the easiest access points for mold spores, so safety glasses or goggles with open vent holes are unacceptable.
Full suites with built-in boots and hoods are also required in order to prevent mold spores from clinging to clothing. In most cases the suit is put on outside of the containment and gloves are then taped to the sleeves of the suit to prevent any mold spores from entering the suit.
In smaller cases, the face may be protected by a simple filtration dust mask such as an N-95 which is easily purchased from Home Depot, but in many cases of advanced mold growth, a respirator is highly recommended. Due to the size of mold spores it is highly recommended to use full face respirators at all times. Half-face respirators (with eye protection) are much better at filtering out air-borne mold spores than N-95 face masks, while full-face respirators are even better than half-face respirators.
In the most severe cases, a full head covering air purifying respirator is used. These units utilize a forced air blower to move air through a HEPA filter. The filtered air is then supplied to a hood that covers the entire head. Positive pressure prevents unfiltered air from entering through gaps. Providers are trained on proper use of their respirators before beginning any remediation procedure. Respirators must be used in compliance with OSHA regulations.
Respirators and other PPE should be worn until remediators are outside the decontamination area. It must also be worn throughout the final stages of HEPA vacuuming and damp-wiping of the contained area, as well as any vacuum filter changes or cleanup of the HEPA vacuum.
Of course one of the primary goals in mold remediation is proper containment, designed to prevent or at least limit the release of mold spores into the air and allowing them to spread to other areas of the property. The containment method is a matter of professional choice, taking into account the size of the mold infestation as well as its location.