After the visual assessment is complete, only then does it make sense to think about mold testing. The decision to do mold testing depends on the goals for the assessment.
Why Test? Usually, mold testing is for determining the extent of mold contamination to help the mold remediators clean it up. Sometimes, it's to help doctors take care of their patients. Other times, mold testing is done to make purchase and leasing decisions.
Mold testing is not always necessary. Mold testing isn't needed if you know you have mold when you already know you do.
Qualified Mold Testers. Mold testing is performed by Certified Mold Inspectors (CMIs) or Industrial Hygienists. The advantage of using a certified mold inspector is that they are usually home inspectors, professionals who know who houses work. Industrial hygienists are microbiologists. Certified mold inspectors work under the authority of an industrial hygienist, usually at a laboratory.
Mold tests are taken for a variety of reasons. The number and type of mold tests taken depend on objectives. For instance, more mold testing may be done for mold clearance when the presence of mold can be established with the initial mold inspection.
Peace of Mind. Home buyers and new renters may want to know if a house is okay for them to live in. Some people are highly sensitive to mold that wouldn't bother most people.
Determine Extent of Mold Contamination. Mold samples don't usually need to be taken to decide if there is mold (but may be needed to prove it). The real benefit is for helping mold remediators establish their scope of work.
Identify Mold Types. Certain kinds of mold should not be present in the air. Sometimes health and legal professionals need to know the specific mold present.
Help Heath Professionals Provide Care. Many times, mold assessments are asked for by patients of allergists and pulmonologists. The results are used to provide care.
Objective Basis for Enforcing a Contract. Objective evidence is often required to show living conditions are unsuitable. Our goal is to help property owners restore their property to habitable condition.
Evidence for Law Suits. To successfully prosecute or defend a case, objective evidence is often sought by mold attorneys.
Several types of mold samples are taken. Most of the time, determining the genus of a mold species is enough--and far cheaper to test for. Special testing is required if a specific species needs to be determined, and is better done by an Industrial Hygienist because they're microbiologists. Most mold testing by a Certified Mold Inspector is done to the genus level.
Mold Air Samples. Samples of the air are taken for a specified volume over a given period to time. The purpose is to find out what is in the air. The results are compared to an outdoor mold sample, used as a control sample.
Air sampling is what is needed to satisfy most mold testing objectives. Rarely are other mold test types needed.
Mold Swap Samples. Swab samples are an easy way to determine the presence of mold without harming the surface tested. The conclusion is the type of mold found only, if any. It cannot be used to determine habitability of a house. Home InSight uses them primarily to determine if specific molds are present that should not be in the air.
Mold Bulk Samples. Bulk samples include 2" x 2" squares of just about anything. The lab will use a piece of adhesive tape to lift the mold of the surface for examination under a microscope. The conclusion is the type of mold only, if any.
Mold Wall Samples. To avoid opening up a wall, wall samples are taken to determine the presence of mold only. A 1/4-3/8" inch opening is needed. Where possible, they are taken around wall outlet boxes.