Viracon, Dow Corning Update Customers on Sealant Concerns
June 18, 2010
As a follow up to the notification sent by Viracon last week to
customers that that they may have received insulating glass units
using a problematic batch of sealant from the company's silicone
supplier, Dow Corning (CLICK
HERE for related article), Viracon today issued a notice to
certain customers updating them on the matter.
The letter, which was sent by Viracon president Greg Silvestri,
states that since last week's notice, "Viracon has worked closely
with our supplier Dow Corning to investigate and identify suspect
982 base that may result in micro bubbles within the secondary seal
of insulating glass units."
The letter continues, "We have been heavily engaged in identifying
specific projects and customers with suspect IG units so we can
work to ensure product safety and uphold our customer service commitment.
We have inspected thousands of units within our inventory and in
customer supply as recommended by Dow Corning, and along with Dow
Corning's investigation and review, believe the scope of this issue
has been substantially narrowed."
In addition, Viracon also says its investigation and testing "determined
that IG units for installation into four-sided mechanically captured
glazing systems need not be inspected for micro bubbles and may
Dow Corning provided USGNN.com with a statement, saying it
has "conducted a comprehensive investigation and found this
intermittent and isolated issue was likely caused by a failed seal
in a drum off pump, but only when certain environmental and/or processing
conditions were also present. The failed seal was immediately repaired
upon discovery. Dow Corning has implemented engineering and process
controls to prevent similar incidents in the future. The drum off
process is dedicated to Dow Corning® 982 Silicone Insulating
Glass Sealant base. No other products are affected due to this issue.
Based on the investigation to date, the potentially affected sealant
is only present in a small percentage of batches within the batch
range 5944452 to 6010209. The time period for this batch range is
limited to material manufactured between March 10, 2010 and May
HERE to read the notice sent by Viracon.
HERE to read the statement from Dow Corning.
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