company personnel, and electric utility personnel worked in teams and visited each home in a door-to-door survey to determine if the homes were safe. Firefighters entered each home and took flammability read- ings, while gas company personnel closed off the gas to each home at the meter. Electrical utility personnel confirmed that electricity to each home was off.
After excavating the gas line, it was determined that a hole caused by a
fault in the adjacent electrical line bled through and burned a hole into the 2-inch natural gas pipeline.
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Figure 7.11 This 2-inch gas pipeline was damaged by a fault in an adjacent electrical line.
U.S. Postal Truck
Figure 7.12 Site map. Comments and Observations
• Natural gas is odorless and colorless, so tertiary butyl mercaptan is added to provide the odor emergency responders commonly call gas. However, the presence of this odor is no indication of the potential flammability readings within a structure, in a confined space, or in open areas.