Four buildings near Manhattan’s Times Square were evacuated Tuesday after an underground buildup of carbon monoxide sparked an underground fire, which blew manhole covers off and sent flames shooting through them to the street. http://www.nytimes.com/2010/04/07/nyregion/07manhole.html
The explosion took place at about 4:30 p.m. Tuesday right by the Novotel Hotel at 220 West 52nd St. The hotel and three other buildings were evacuated, and West 52nd Street was closed from Broadway to Eighth Avenue.
No one was hurt in the explosion, which New York Fire Department officials said happened when power cables under the street caught fire, with carbon monoxide and smoke then building up.
One witness, Vincent Massarelli, told the New York Daily News, “There were seven-foot flames in the street.” http://www.nydailynews.com/news/2010/04/06/2010-04-06_underground_fire_on_w_52nd_st_makes_asphalt_explode_four_buildings_evacuated_no_.html
Authorities evacuated the four buildings because dangerous levels of carbon monoxide were detected in the lower levels of those structures.
Carbon monoxide levels reached as high as 700 parts per million, while a house CO alarm would go off at only 35 parts per million, a fire department official told the News.
The explosion took place not far from the Ed Sullivan Theater on Broadway, where David Letterman does his late-night show.
“Carbon monoxide levels reached as high as 700 parts per million, while a house CO alarm would go off at only 35 parts per million, a fire department official told the News. ”
It would have to be 35 ppm for 30 days for a UL 2034 rated detector alarm. In fact the range is 30-70ppm for 30 days before it sounds an alarm….OSHA doesn’t allow 70 ppm for 8 hours let alone a month like a UL rated detector.