Protection from CCA
Seal-It International Inc. has responded to customer driven request for a solution to the health problems linked to Chromated Copper Arsenate (CCA) treated wood. Seal-It has contracted the services of Enviro-Test Laboratories, a division of CHEMSPEC ANALYTICAL LIMITED, to determine the efficiency of Seal-It’s new product, CCA Sealant.
Pieces of CCA treated wood of equal surface area, cut from the same 2 x 6 inch dimensional piece of lumber, were wiped with a sterile cotton swab that had been dampened with distilled water. The Laboratory provided one plastic bottle for each swab to be placed in, to be returned to the lab. Two separate series of swabs were taken. The first set of swabs are on the lab report marked “Date Received: 03-MAR-04”, the second set are marked “Date Received: 17-MAR-04”.
In the 03-MAR-04 report the 2 pieces of CCA wood were swabbed and tested. Wood piece stamped no. “1” received 2 applications of CCA Sealant as per instructions; wood piece stamped no. “5” received no application of CCA Seal. The third swab marked “Control” is just that, the Lab wanted 1 swab that had not been used on any piece of wood to get a “base line” of the three compounds in the test (Chromium, Copper and Arsenic).
In the 17-MAR-04 report 2 different pieces of CCA wood from the same piece of lumber were swabbed and tested. In this series of tests there again was a “Control” swab delivered to the lab. The piece of wood stamped no. “2” had been coated twice with Seal-It CCA Sealant then lightly washed before a sample was taken to simulate the results of the application contractor washing the sealed object following sealing. Piece of wood stamped no. “6” had been coated 3 times then lightly washed.
Seal-It CCA Sealant will bring some impurities to the surface while locking the majority into the sealed object. Washing the samples before swabbing will remove the “raised” chemicals to give a more accurate sampling of the concentration of CCA now exposed. Seal-It believes that a more vigorous washing, i.e. pressure wash, may remove even more of the surface CCA, while still leaving the CCA Sealant to protect for years to come.
In Conclusion, the 03-MAR-04 results show that there can be an over 50% reduction in the exposed CCA on the sealed surface with minimal effort, (As: 12.9 to 6.0 micro grams per swab; Cr: 10.4 to 4.4; Cu: 11.9 to 4.0). With a bit more effort the 17-MAR-04 results show that an over 90% reduction can be achieved.