should i take my own vermiculite samples for testing?

Photo: Gil Strachan

​Although vermiculite is not an asbestos product, it is estimated that about 10-30% of vermiculite insulated homes have elevated levels of asbestos due to contamination during the mining process.

​Vermiculite is usually found in attics, and in order to collect quality samples for laboratory testing, you should be aware of the following:

• Asbestos contamination will not be consistent throughout the vermiculite used in an insulated spasce. There will be areas with higher or lower levels, and some with no measurable asbestos level. You need to take samples of the insulating material from different locations throughout the insulated area, and combine them into one sample. Multiple sampling may identify conditions of mixed asbestos and non-asbestos vermiculite that a single sample would miss.
• Asbestos crystals are heavier than vermiculite and over time, as a result of wind and other sources of vibration, the asbestos crystals accumulate closer to the bottom of the insulation. To ensure your samples are unbiased, you must reach the bottom of the insulation layer and take your samples from there.
• Pinchin Laboratories states "Avoid creating and breathing any more dust than necessary during this collection and do not remain in the area longer than necessary. The U.S. EPA and Health Canada recommend that you use a respirator to reduce the dust you breathe during this collection. You can purchase a NIOSH approved half-face P100 respirator from most hardware stores or safety suppliers.
  Follow the instructions provided with the respirator regarding fitting and maintenance. This respirator should not be used for major disturbance of vermiculite which would be encountered during renovations in the attic or for removal of the material. Try to avoid tracking the insulation or dust into the living space of the house, using plastic sheets below areas of work.
• The presence of other materials, such as wood shavings, fibreglass and cellulose insulation can make quantitive testing more difficult.
• Environmental laboratories may have differing requirements, but typically ask that a certain amount of vermiculite be double-bagged and delivered with a name, email address and phone number, as well as the address of the property in question, and a "Chain of Custody Form for Vermiculite Analysis."

Although homeowners can choose to collect their own samples, it may be prudent to leave this work to professionals who are licensed in asbestos abatement, to be better assured of proper sample collection and preparation. Moving the chain of custody away from the homeowner, the prospective purchaser and their Realtor, as well as their home inspector will reduce potential liability - especially where the sampling and testing is part of an Agreement of Purchase and Sale.

Licensed asbestos abatement professionals already have the knowledge and the skill set required to take valid, unbiased samples - as well as the respirators and other protective equipment to complete the sample collection in a safe, responsible manner.

Photo: Carson Dunlop