With respect to public swimming pools, the United States may be able to learn much from Europe, Australia and Canada. Current legislative trends in the U.S., as evidenced by law changes in California and Florida, are bucking thoughtful policy in these other parts of the world. Recent changes to state law permit swimming in public pools with as high as 50 full parts chlorine. European standards require pools to be closed when total chlorine exceeds as little as 1.5ppm. Further, the European standard permits a 5ppm minimum chlorine level when combined with .4ppm. Jeff Grotte , a chief mechanical officer in the water treatment industry, notes that the European standard goes further in mandating that daily bather loads are counted and water exchange rates are maintained at a rate of 35 liters per swimmer , per day. Under the standard, pools must be closed when maximum daily bather loads are exceeded.