First, know what a cross bore is. It is where underground utility lines cross over each other.

The reason you need to know this is sometimes in rare cases a natural gas pipeline might actually be run through a sewer pipe, and if a plumber unknowingly strikes a gas line while cutting through a sewer pipe for a repair, natural gas could enter the sewer system creating a very dangerous situation!

For this reason, it's very important that everyone digging call 811 to have all utility lines clearly marked.

Always assume there is a possibility of crossed lines. If a natural gas pipeline is hit:
 

• Leave the premises immediately
• Instruct others to leave right away and stay away
• Call 911

DO NOT

• Operate any electrical appliances in the area
• Operate any pipeline system equipment
• Turn on vehicles, appliances or lights
• Use anything that might create a spark, including a cell phone