What is a Level 1 gas leak in Massachusetts?

LAWRENCE, Mass. — What is a grade one gas leak?

A grade one gas leak poses a danger to people and property and should be dealt with immediately, according to the Massachusetts state guidelines.

Fire officials said on the scene a grade one gas leak must be repaired within 24 hours of discovery.

"I think this is above a grade one...this was a high-pressure leak," Lawrence Fire Chief Brian Moriarty said on scene Friday morning.

Massachusetts General Laws include the following:

(2) A Grade 1 leak shall be a leak that represents an existing or probable hazard to persons or property. Grade 1 leaks require repair as immediately as possible and continuous action until the conditions are no longer hazardous. The gas company shall immediately schedule a completion of repairs and the condition shall be kept under continuous surveillance until the hazard or source of the leak is eliminated. Whenever appropriate and feasible, a gas company shall notify the fire department and chief law enforcement officer in each city or town where a Grade 1 leak is identified.

The state defines a level one gas leak here.

Live updates: More than 100 people evacuated after 'major gas leak' in Lawrence