A mold test can then reveal the presence of mold invisible to the naked eye. Colonies are ubiquitous in all environments and actively participate in recycling organic matter by degrading plant material.
An initial check to see if the house is a problem can be made when an occupant appears to be experiencing discomfort. The occupant should leave the house for a few days if his symptoms improve while away and return when the individual returns home. It is possible to conclude that the air quality is not adequate.
Sampling and analysis of biological contaminants (mold)
The analysis of the results of the mold test performed in the laboratory are accredited by the Ministère du Développement durable, de l'Environnement et de la Lutte contre les changements climatiques (MDDELCC) of Quebec. All mold samples collected are analyzed in the laboratory and approved by microbiologists specializing in microbiology. The laboratory technicians are certified by the Canada Mortgage and Housing Corporation (CMHC). All laboratory operations are carried out according to the international standard ISO/CEI 17025. All sampling methods comply with the standards and regulations of the Institut de recherche en santé et sécurité au travail du Québec (IRSST) and Health Canada's occupational health and safety regulations. AIRTESTS MATTESTS sampling technicians are continuously trained according to the protocols prescribed by the laboratory.
Depending on the nature of the specific needs of each situation and the time available to obtain the mold test results provided by the laboratory, here are the different sampling methods used by AIRTESTS MATTESTS in the search for indoor environmental contaminants
Method 1 - Spores Trap Air Mold Sampling
Microbiological surveys of total mold spores in the air are carried out using a spore trap. The parameters obtained by these samples are the enumeration of total mold spores in the air and the identification of mold genera.
To establish this type of microbiological air survey, total mold spores (viable and non-viable) must be sampled to count the total fungal particles in the air accurately. To do this, air samples are collected using an Air-O-Cell pump and cassette. This spore trap sampler pumps 75 liters of ambient air through the cassette for 5 minutes (or 150 liters for 10 minutes). The sampling matrix is equipped with a microscope slide coated with an adhesive film on which the particles present in the sampled air are impacted. The sampling techniques for this mold test apply to viable and non-viable mold spores (total spore count).
Intra-wall, intra-ceiling, or intra-floor sampling can be performed to inspect the air behind walls, ceilings, and floors. It will be possible to perform this analysis with a probe that passes through an opening. The sampling time will be reduced to 2 minutes for a total of 30 liters of air. The sampling time is thus reduced since the environment behind the walls is generally dustier. Dust can limit and compromise the reading of results.
Method 2 - Sampling of molds in the air by Bio Impaction
The parameters obtained by these samples are enumeration, identification to genera or species. Only viable molds in the air are identified with this method, that is to say, that it does not detect dead molds that can, however, remain allergenic.
Microbiological air samples are collected using an Andersen-type impinger. Air enters the unit from the top through the impaction process, and the micro-organisms are separated and stored in an appropriate culture medium by centrifugal force. The culture medium used for molds and yeasts is MEA or PEA agar. The samples are held at 4°C until they are returned to the laboratory, where they are incubated for several days.
The results of the laboratory analyses are given in CFU/m3 (Colony Forming Unit/Cubic Metre of air). The interpretation of the data is made by comparing the volumetric results between indoor and outdoor air. In addition, both types of air should have a similar distribution of mold types but a lower concentration of molds in indoor air. These techniques apply to viable molds only.
Bio-impaction research is most useful for in-depth investigations. This technique requires a laboratory waiting period of up to two weeks for incubation, subculturing, and re-incubation of live material (agar cultures). In-depth environmental research is done on a case-by-case basis through elaborate, custom-built submissions.
Method 3 - Surface Mold Swipe
For microbiological analysis, a sample of surface contaminants is collected using a specially designed swab to collect and transport micro-organisms. This sampling method for testing for mold is defined as "Contact Swab."
For example, an area of 100 cm2 (10 cm x 10 cm) is sampled with a swab to obtain the CFU/100 cm2.
The sampling applies to viable molds only; however, it should be noted that these results do not reflect the quality of the indoor air. These samples are generally taken inside ducts or on ventilation grills and any other surface of suspicious appearance. The parameters obtained are mold counts, identification of mold genus, and identification of surface mold species.
Method 4 - Sampling of mold on surfaces by tape lift
Samples are taken with a tape lift applied to the mold. This method is generally used to establish a partial identification of molds. However, the results do not reflect the quality of the indoor air.
Mold due to water infiltration
In an indoor environment, the main contributor to mold growth is water. Whether it's a leaky roof, a crack in the foundation, a burst plumbing pipe, a sewer backup, and more. All of these situations should be taken seriously. Without water, there is no fungal growth possible. It is, therefore, the essential element to monitor to avoid fungal contamination.
In modern buildings, mold can be caused by a variety of factors, including:
• Flooding from heavy rain and sewer backup.
• Leaks from the roof, basement, or plumbing.
• Waterproofing of the building preventing the evacuation of accumulated moisture.
• Water infiltration caused by design and/or construction defects.
• Moisture sources such as showers, cooking appliances, and others.
• French drains that have become dysfunctional due to iron ochre
• Excessive moisture of any kind in the indoor environment.
There are three categories of water conditions for which the extent of the problem depends.
Clearwater: This is so-called clean water from a broken supply pipe, an overflowing bath, or sink.
Greywater: This water may contain bacteria. It can come from a washer discharge, a toilet with urine in it, or a dishwasher.
Blackwater: This is water contaminated by micro-organisms (viruses, bacteria, and molds). It is unhealthy and can cause serious health problems. It comes from sewer backups, among other things.
Regardless of the source of water infiltration, it must be dealt with quickly. It is essential to clean up and dry out the seepage materials as soon as possible. Sometimes the removal of damaged materials is required. This is even more important in the case of a sewer backup since the water may contain fecal matter and therefore bacteria. A mold test is essential in this situation. Contaminated wood and gypsum should be discarded. Other surfaces should be disinfected. The problem must also be repaired to prevent further water infiltration into the home.
An air quality analysis will provide a better understanding of the impact of the presence of water to assess the true extent of the problem in the indoor environment.