When you pour liquid chlorine into your swimming pool, you expect it to be effective. After all, it's labeled "pool-grade" and priced accordingly. But what if that assumption is wrong? A recent report ...

It was a seasonably warm evening that hinted at the summer to come, and Artie Verderamo paused over the limpid water of the backyard pool he was tending in Glen Ridge. Verderamo, a technician with ...