Whenever I see concrete paving, blocks, bricks or stone being grooved or sawed, two observations hit me.
The first is the obvious noise the saws generate and the hearing loss that can result from years of noise exposure if no ear protection is used. The second is the dust cloud, which, if no respirator/HEPA filters are utilized, can bring crippling or fatal injury to the lungs silicosis.
The name silicosis comes from the Latin silex, meaning flint, a fine-grained quartz, chemically known as silicon dioxide (SiO2) about the most common mineral on the planet. Quartz and silica are harmless except in two circumstances: If you are unfortunately caught by a rock fall or you breathe silica dust for years.
Mining is part of our Western legacy, and in no other activity than mining was silicosis as severe. When steam and compressed-air drills successively replaced double jacking (hand drilling), they created much more dust. Air drills were then improved by injecting air down through the drill bit into the hole, cleaning the hole and allowing even faster progress at the mine face generating even more dust.
In this environment, drillers died in six to 24 months, becoming respiratory cripples. They appeared to have consumption, the term for tuberculosis. After microscopic, silica-dust particles, millions of Lilliputian razor blades, were discovered within fibrotic nodules in scarred lungs, miners consumption became silicosis, technically an environmental pneumoconiosis from the Greek pneumon, or lung, plus konis, or dust.
One widow was reported to have successively had seven husbands, all miners, lost to silicosis. The U.S. Supreme Court struck down state safety laws (those few that existed) and essentially allowed that if a man willingly accepted a hazardous job, the employer was not responsible for the consequences. Some drillers had been known to pour water onto their drills from coffee cans. It helped for down-holes but not for up-holes. Ironically, technology eventually and somewhat unwittingly ameliorated the problem. Injecting water down through the drill bit cooled it, cleared the hole better and incidentally reduced dust.
Silicosis, as a disease, has few symptoms until it is too late; the damage is done. In other words, when there is a cough, shortness of breath, or detectable changes on chest X-rays, schools pretty much out. Another consequence is that silicosis, in a process not completely understood, increases the risk of tuberculosis. Its ounces of prevention versus pounds of no cure.
Silicosis is most prevalent in the construction trades in any activity that produces silica dust from quartz-bearing rock and concrete. Wet concrete and masonry saws and wet drills obviously help. Low-silica substitutes can be used for sand blasting. Dust control systems should be essential for work in closed or confined spaces, and respiratory protection (another complex subject) is recommended.
The National Institute for Occupational Safety and Health, or NIOSH, not to be confused with OSHA, has a very informative article, including worker case histories, called: Preventing Silicosis and Deaths in Construction Workers. Its online at www.cdc.gov/niosh/consilic.html. Its well worth the read.
www.alanfraserhouston.com. Dr. Fraser Houston is a retired emergency room physician who worked at area hospitals after moving to Southwest Colorado from New Hampshire in 1990.