BOSTON (AP) -- The family of an electrician who died in a 2010 propane explosion has settled a lawsuit against a propane distributor and a plumbing company for $7.5 million.

A lawyer for the family of William Nichols says the family and two other people who suffered permanent injuries in the blast in Norfolk settled last week for a total of $22.5 million.

The lawsuit alleged that EnergyUSA under-filled a new propane tank causing the chemical odorant which had been added to fade. This made the leaking propane odorless and undetectable.

Smolinsky Plumbing and Heating allegedly failed to tighten a connection that led to the leak.

Investigators said the propane had "virtually no odorant."

Nichols, of Blackstone, suffered burns over 80 percent of his body.

The explosion led to newly proposed regulations for propane.