OSHA has cited three construction companies and 14 subcontractors for 371 safety violations, totaling $16.6 million in penalties.

The Feb. 7, 2010, explosion at the Kleen Energy plant construction site was felt as far as 40 miles away.

OSHA officials say the construction companies cut corners to gain a $19 million incentive if they finished construction early on the plant. Published reports say in the weeks and months leading up to the explosion, employees were working seven-day, 84-hour weeks.

In late June, a U.S. Chemical Safety Board investigation revealed the explosion was most likely caused when natural gas was used during a routine gas purging procedure. The gas found an ignition source. Welding and other work was being performed nearby.

O&G Industries, the project’s general contractor, has been issued 119 willful and 17 serious citations with penalties totaling $8.3 million. Keystone Construction and Maintenance was issued 94 willful and 16 serious citations with fines of $6.6 million. Bluewater Energy Services, the commissioning and startup contractor for the plant, was issued 12 willful citations and 8 serious citations totaling $896,000. In addition, 14 subcontractors were also cited and fined.

O&G says it plans to contest the fines.

As a result of the explosion, OSHA will be issuing a warning letter to natural gas power plant operators regarding the dangerous practice of cleaning fuel gas piping using natural gas.

Natural gas seeping from pipes caused an explosion at a San Diego hotel construction site that injured a firefighter and 13 construction workers. Three of those injured required weeks of hospital care for critical burns, according to the Union-Tribune. The hotel’s fourth through seventh floors were destroyed in the explosion.

Cal-OSHA assigned most of the blame for the blast to Sherwood Mechanical, Inc., a plumbing and heating contractor. Sherwood faces fines of $67,500 for four serious violations:

• The company’s Code of Safe Practices didn’t address methods for testing concentrations of natural gas, procedures for purging gas line or methods to control operation of gas.
• Employees weren’t instructed on methods for testing natural gas concentrations, procedures for purging gas or methods to control access to valves and pipes.
• Piping being purged of air wasn’t vented outside from an enclosed space, and the vent wasn’t closed after air was purged.
• The company allowed natural gas to accumulate in a room to dangerous levels and failed to test the concentration of gas in the room.

A report says workers trying to flush air out of pipes feeding a hotel boiler inadvertently allowed natural gas to leak into a fifth-floor mechanical room.

After the gas built up in the room, any number of electrical installations could have been the ignition source, including light switches and lighting itself.