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Inspirational Quotes

Behold the turtle. He progresses only when he sticks his neck out.
James Conant

Only those who will risk going too far possibly find out how far one can go.
T.S. Eliot


  • Shorter is Better
  • Targeted is Better

Expect 3 Separate Newsletters for June

  • Carpeting
  • HVAC
  • Construction Defects

What's That Smell? New Carpeting (4-PC)

     4-Phenyl Cyclohexane (4-PC) is a gas produced from a reaction between styrene and butadiene in synthetic latex or styrene-butadiene latex used in the backing of most carpeting. 4-PC is linked with upper respiratory tract and eye irritation, skin rashes and allergic reactions. Normally, 4-PC off-gasses in about 72 hours. Where carpeting is direct-glued to the slab, carpeted adhesives (normally water-based) also can emit odors. These adhesives contain volatile organic compounds (VOCs) which may require months to completely off-gas.

Specify Dry or Low Emitting Adhesive

     The Carpet and Rug Institute's green label identifies carpets and adhesives that have been tested for emissions and meet specific standards. Ask your installer for emission test results (available from the retailer or manufacturer) for your carpet and padding and review the MSDS for the adhesive.

     AET Evaluation: AET's clients including schools, daycares, hospitals and commercial office buildings periodically perform Baseline IAQ testing to evaluate carpeting during new construction and major renovations. Results are compared to LEED Standards of 6.5 ug/m3 (4-PC) and 500 ug/m3 (TVOC).

     Recommendation: Ventilate/flush-out the work space during carpet installation and for 48-72 hours after installation. LEED recommends performing building flush-out by supplying a total air volume of 14,000 cfm of outdoor air per square foot of floor area while maintaining an internal temperature of at least 60̊ F and RH of no higher than 60%.

     Carpet Rip-Out:  Old carpeting is a reservoir of past sins. Remnants of every spill, pet or contaminant which has been tracked in is still found in the carpet. Dust mites also thrive in carpeting and are known to cause allergies and trigger asthma attacks. Steam cleaning, even in combination with HEPA vacuuming, is not 100% efficient.

     Further during carpet rip-out, dust (including mold spores) become airborne. Particles 1 micron in size remain airborne for 8.5 hours before they settle out. Smaller particles can remain airborne even longer and can become easily re-suspended.


Vacuum old carpeting (preferably HEPA vacuum) prior to its removal.
  • Roll carpet inwards during removal.
  • Remove carpet pad (when present).
  • Vacuum subfloor before new carpet is installed.

     Where carpeting is believe to be highly contaminated or located in occupied sensitive areas, plastic barriers should be constructed to control dust. Carpeting can also be misted with water to minimize dust generation.

4 Ways to minimize dust contamination to carpeting:

Entryway mats have shown to reduce residues in carpets by 25-33%.
  • Removing shoes at the door have been shown to reduce dust levels 10 fold.
  • Vacuum carpet regularly. One way to monitor dust levels in your carpet is to use a vacuum with a dirt finder; These vacuums have a red light to show where dirt is located and a green light to show where the carpet is clean.
  • Many experts feel that the best floors are wood, tile or other hard surfaces (especially in childrens bedrooms). Bare floors should be vacuumed and damp mopped frequently to prevent dust build-up.

Chinese Drywall: Latest Update

     EPA analyzed 2 Chinese drywall samples collected by Florida DEP from affected homes in FL. Results were compared to 4 samples from US manufactured drywall. Samples were separated into 3 layers (1) acrylic paint (2) top/bottom paper (3) gypsum.

Lab Results





83-119 ppm


United States


240-1130 ppm

     Two organic compounds were found in the acrylic paint layer of the Chinese drywall. The US drywall was not painted.

New VA Mold Law

     In March 2009, the Virginia Residential Landlord and Tenant Act was signed into law by the Governor. This law primarily affects apartment building owners and other housing clients as detailed in the provisions listed below. Contact AET for any assistance you may require in compling with the provisions of this Law.

  • requires landlords to certify that the premises they are renting are mold-free and pay for their tenants expenses if the certification is wrong.
  • requires landlords to maintain premises in good condition to prevent mold growth and to respond promptly to notices of mold contamination.
  • requires landlords to provide written report as part of move-in inspection and disclose any visible evidence of mold in the dwelling interior.
  • where visible evidence of mold, the tenant shall have the option to terminate lease
  • should tenant take possession, the landlord shall promptly remediate mold no later then 5 business days after notification and must reinspect the dwelling unit to confirm mold has been removed.
  • landlords must temporarily vacate tenants where mold can affect the health and safety of the tenant.
  • temporary relocation can include comparable dwelling unit or hotel room. Landlord is responsible for the expense associated with tenant relocation and the cost of all mold remediation.

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