Toxic Acid Cloud Forces Evacuation of Hughes Plant

A reddish-brown nitric acid cloud that escaped from a Hughes Aircraft facility in El Segundo sent seven people to the hospital and forced the evacuation of 400 employees from six buildings Thursday.

What caused the release and exactly how much of the chemical leaked out have not been determined, said Don Johnson, a spokesman for the El Segundo Fire Department.

Nitric acid, a strong corrosive, is considered highly toxic. Hughes uses it to etch electronic circuit boards for airborne radar systems. It was the first time nitric acid has leaked from Hughes Radar System Group facilities, part of the larger aircraft complex near the intersection of Maple Avenue and Nash Street, Johnson said.

Johnson said a Hughes plumber was the first to notice the fumes, which were coming from a storage area. The report of a chemical leak was reported to the El Segundo Fire Department at 10:10 a.m.

Sixty fire and rescue workers from El Segundo, Hawthorne, Manhattan Beach, Los Angeles County and Hughes Aircraft converged and evacuated people from Hughes buildings, Johnson said. Police sealed off nearby streets, all in a commercial and industrial area.

Six roofers, who had been working at a Hughes facility in the path of the toxic cloud, and a police officer reported shortness of breath and lung discomfort and were taken to the Robert F. Kennedy Medical Center, where they were treated and released.

Johnson said the cloud had largely dissipated by 11:45 a.m., and a hazardous materials crew in protective suits then inspected the storage area.

Hughes spokesman Richard Dore said 78 gallons of the substance, in one-gallon jugs, was in the storage area. Dore said the Hughes installation had never been cited for safety violations by federal or state agencies.