Two Philadelphia U.S. Postal Service distribution centers face $497,000 in fines for allowing inadequately trained employees to perform work without the proper protective equipment while being exposed to live electrical parts, the U.S. Department of Labor's Occupational Safety and Health Administration said Tuesday.

OSHA cited the Postal Service with four willful violations at the network distribution center at 1900 Byberry Rd., and with three willful and one serious violation at the Processing and Distribution Center at 7500 Lindberg Blvd.

In a statement, the post office said it prides itself on its safety record, but "regardless, one accident, or the potential for one accident - on the road, in a post office or a mail processing plant - is one too many.

"We will review OSHA's concerns and make necessary adjustments to continue to ensure a safe working environment for our employees," the statement said.

Willful violations mean that the employer knew conditions were unsafe, yet chose to ignore the hazards. Serious violations mean the employer should have known that conditions were unsafe.

Representatives from the American Mail Handlers Union and the American National Postal Workers Union alerted OSHA to safety problems here and elsewhere around the country. Citations were also issued at a Pittsburgh mail processing center.