"Following up on our conversation over the phone yesterday. Attached is a graph which shows the Crude 2 fin fan (E-5112, air vs. cooling kerosene) performance during the summer of 2005. The graphs compare actual performance to the original design by tracking the overall heat transfer coefficient, U in Btu/hr*sqft*F (Uactual/Udesign vs. time). During the summer of 2005 we cleaned the fin fans by three difference methods. • May 15: We had one of your competitors in Anchorage clean our fans. The results were not great. • June 15: Our on-site contractor washed the fin fans with fire water only. NO impact on cooling. • August 20: Fin Foam cleaned the fans. The results were very good. The graph shows the rate of decline in fin fan performance over time as well as how effective each of the three methods was at cleaning. Far and away the best results were achieved with Fin Foam in August. Obviously achieving a Uact / Udes of 1 is ideal. We achieved 80% of design in August with Fin Foam, which I believe is as good as we can get given the age of the fans and amount of mineral build up on the fins from years of washing. Please feel free to use my name as a customer reference as I feel that you guys have done an outstanding job for us. The data speaks for itself. I was also impressed by the level of professionalism and awareness for our safety culture by both you and your staff. I would recommend your services to anyone considering cleaning fin fans. "