Background:
LeadCheck® Swabs are highly specific for lead. No other metals can react
with the LeadCheck® reagents to turn the
swab tip pink. This specificity allows LeadCheck® to be used for testing on any surface
without the fear of false
positive results. If LeadCheck® Swabs turn pink, lead is present. However brick painted
surfaces offer special
challenges to the LeadCheck® System:
- Brick can be porous and therefore highly absorbent. The LeadCheck® dye can simply be
drawn into the surface making the developed color difficult to see.
- The pigment in red brick can leave a red deposit on the LeadCheck® Swab tip.
Method: The following methods will allow brick painted surfaces to be tested with
LeadCheck® Swabs.
For porous brick:
- Remove a paint chip from the surface and crumble onto a piece of plastic wrap or
wax paper. Activate a LeadCheck® Swab as described in the instructions
and rub into the paint.
- Alternatively score the paint down to the brick substrate. Activate a LeadCheck®
Swab and rub on the exposed cross-section of paint. Look for pink color development
on the exposed paint edge.
For red brick:
- Test for nonspecific color transfer to the swab tip by crushing the B ampoule of
the LeadCheck® Swab and rubbing the clear liquid on an exposed section
of brick. If the swab tip turns red remove a paint chip
from the test surface. Follow the method described in porous brick (above) to test
the paint chip.
*LeadCheck® Swabs are a versatile and sensitive screening tool for the detection of lead on any surface. This applications note provides a suggested
method to allow testing for a specific application. Additional information and help are available by calling 800-262-5323 or 508-651-7881.
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