Lehighton firemen are currently engaged in their most important annual project - the cleaning of chimneys in the borough. Since the two fire companies began cleaning chimneys more than a dozen years ago, chimney fires have been reduced by more than 95 percent annually. Since the "Chimney Sweeps" began making their rounds, there has been an average of two chimney fires per year. The most chimneys cleaned in one year was in 1969, when the firefighters clean 343 chimneys.