| CALIFORNIA INTERNATIONAL CHEMICAL 100 Stony Point Road, Suite 220 Santa Rosa CA 95401 RE: Report on Two Tests of Chlorine Affects on Vinyl Pool Liner The liner sample used in both of these studies came from the same source, a standard blue vinyl pool liner with irregular black markings, with an initial thickness of 0.596 mm. In all tests the final thickness was again 0.596 mm., that is there was no measurable change in the thickness of the liner. None of these tests resulted in either an erosion of the vinyl or an absorption of water and swelling of the material. Two tests were performed. one was a field study where one large vinyl piece was attached to the base to the gas chlorine delivery wand and a smaller piece tied to the wand to be in the rising bubbles of chlorine when dispensed into the pool (FLAG). A third large piece was to have been used like the first, but the water movement from the rising chlorine bubbles dislodged this piece, so that it was used in only one partial application (CONTROL). The other test was a laboratory study. Three pieces of vinyl were placed in tall beakers filled with tap water that had been adjusted to different pH levels. The acid pH with muriatic acid (HC1), the alkaline with caustic soda (NAOH) and the neutral with a small amount of pH7 buffer (sodium phosphate buffer). The pH of each was checked prior to the addition of the vinyl, after the addition, after ten days and at the termination of the study. Weights of the vinyl pieces were obtained prior to placement in the beakers and at the termination of the study, in both cases after drying at 50 C. All pieces were heated briefly in a drying oven to 50 C and weighed prior to installation. At the close of the studies a similar drying method was used on the field study pieces, but the laboratory study samples were dried for 24 hours at 50 C. CONCLUSIONS In the more carefully controlled laboratory experiment weight losses on the order of 0.5% were observed, with the highest loss on the sample stored at pH 7. Since vinyl is known to be non reactive with water at pH 7 it is obvious that the accuracy of the data is plus or minus 0.5%. All weight changes in the field study were much less than 0.5%. The vinyl sample that acted as the control had the greatest weight gain. Experimental procedure had the greatest effect on the observed weights. The slight changes in pH after added the vinyl indicated that there was some reactive compound on the surface of the vinyl, most likely a carbonate based mineral surface treatment or dust that was not removed by rinsing with tap water. The smallest sample in the field experiment was exposed to the stream of chlorine bubbles on a commercial wand for more than one week of application. Earlier studies have shown that this is the area of the most chemical activity while gas chlorine is being injected into the water. There was a slight stain on this vinyl sample after removal in the area where the nylon tie contacted the vinyl. This stain was superficial on the vinyl. It was, most likely, derived from the nylon attachment cord. This small piece of vinyl was blasted with actively dissolving chlorine gas equivalent to the effects of several years of treatment on a vinyl pool liner, with no measurable impact. There was no alteration of the vinyl piece attached to the base of the wand. This agrees with earlier studies that showed that the region below, a properly designed, chlorine wand is continuously washed by general pool water as the chorine is injected and should not be affected in any way by this treatment. Neither gas chlorine or pH, in the range of 2.5 to 9.5 had any effect on vinyl. Colors were not bleached nor was there any measurable loss or gain of vinyl or water within the accuracy of the experiment. Even with the severe treatment of the small "FIAG" in the chlorine bubble stream there was no visible loss of pattern or bleaching of the basal color from the vinyl.
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