Tuesday, August 01, 2006

Why OSHA Has A Confined Space Standard

OSHA has what's known as a "confined space" standard. (It's not named after this blog.)

Confined spaces are areas that are too small and cramped for workers to regularly work there, but where asphyxiating atmospheres can easily build up an kill anyone in the space. The most common confined spaces are sewer manholes where rotting sewage or vegetation can generate high levels of hydrogen sulfide or eat up all the oxygen.

OSHA's confined space standard requires monitoring of confined spaces before entering, and a means to rescue workers without rescuers entering the space unless absolutely necessary, and unless their equipped with an air-supplying respirator.

The National Institute of Occupational Safety and Health (NIOSH) reports that more rescuers have died in confined spaces than original victims. And it's not hard to understand why. You see you buddy passed out down in that pit, and your first instinct is to jump in and save him. That's why the standard also requires training -- training workers not to jump in and try to save someone (without training, an air-supplying respirator and backup), or you'll become the next victim.

An article that appeared yesterday in a Canadian newspaper describes a confined space incident in which three workers died:

A 30-year-old subcontractor from Montreal died on the scene Saturday after using argon gas to weld inside a large metal tank at the facility in Lac Brome, about 100 kilometres southeast of Montreal.

When the younger man fell unconscious, the 55-year-old attempted to enter the tank to rescue him, but was also overcome with fumes. The woman, a mother of three young children who was also trained in first aid, also fell unconscious after entering the tank.
The article notes that this incident bears a striking similarity to two other recent tragedies:

On May 17, 2006, four people died after being overcome by hydrogen sulfide gas at a Teck Cominco's Sullivan mine in Kimberley, British Columbia. Chris Faulkner, a subcontractor who checks water quality, went missing inside the underground mine and was found two days later by Teck Cominco employee Robert Newcombe Douglas Lloyd Erickson, who was able to dial 911 before succumbing to the gas himself. The two B.C. paramedics who responded to the call, Kim Weitzel and Shawn Currier, also died when they went into the mine. Their bodies were eventually retrieved by firefighters equipped with oxygen masks.

On January 10, 2003, a maintenance supervisor went missing inside the hull of the Sea Link Rigger, a 342-foot-long barge. One colleague found him in an enclosed space within the hull and attempted to retrieve him. One by one, several other workers also attempted to access the space to rescue their colleagues, but eventually lost consciousness. Ultimately, four workers died of oxygen deprivation.
And speaking of confined spaces, watch out for manure pits.
Air emissions from livestock manure pits contain hundreds of chemicals, including highly toxic hydrogen sulfide, microbes, acids, alcohols, ammonia and nitrogen compounds that contribute to global warming and promote weed growth in surface waters, according to several scientific studies.

"An overview of studies of VOCs (volatile organic compounds) emitted from animal facilities indicates that hundreds of compounds are present," according to a U.S. Department of Agriculture report. "Malodorous emissions (from livestock manure) can negatively impact health."

Scientists in North Carolina identified more than 300 chemicals in air emissions from hog barns, according to the USDA report.

Hydrogen sulfide can be lethal if inhaled in relatively small amounts, according to government data. Dozens of farmers in several states have died after falling into manure pits and being overcome by hydrogen sulfide or methane fumes.

In 1989, five dairy workers died of methane asphyxiation when one of the men fell into a manure lagoon at an Upper Peninsula farm and the others went in to rescue the men ahead of them.
More confined space information here.