The public consideration of fracking, and the risks to workers posed by dust created when the sand used in the process is handled, prompts me to speak out about my experience with my father's silicosis.

He was a shaft miner, before OSHA, air cleaners and facemasks. He didn't seem to be experiencing problems much before the end of 30 years following his two years of mining. He might have thought that breathing silica dust hadn't hurt him.

But silica dust never gets out of the lungs, meaning that every breath taken causes another cut, which heals because it is small. Millions of breaths later, there are millions of cuts, until the entire lung is scar tissue and scab, having no elasticity.

By the time I was 10, I knew my dad couldn't walk more than a few steps without heaving. By the time he died at 69, he could scarcely breathe. I understood later that the lack of oxygen made him impotent, a condition no miner would prefer to have, I'm sure.

Sister Rafael Tilton, Rochester