With the entire state’s attention focused on Farmington following Monday’s tragic explosion, we are reminded of how often service in public safety is a family affair.

Capt. Michael Bell was killed in the explosion, and his brother, Fire Chief Terry Bell, was injured. Together, they have given more than 70 years of service to the Farmington Fire Department. Their father, Jack Bell, who died in 2000, served the same department for 49 years.

Also injured were Capt. Scott Baxter and his father, firefighter Theodore Baxter.

As of Wednesday, Terry Bell and the Baxters were in critical condition at Maine Medical Center in Portland. Capt. Timothy Hardy was in satisfactory condition at the same hospital.

Hardy’s father, Tim Hardy, is now acting fire chief in Farmington.

(Firefighter Joseph Hastings was released from the hospital Wednesday. Deputy Chief Clyde Ross, was treated and released from the hospital Monday. Larry Lord, the building maintenance worker who first noticed the propane leak and moved people to safety, is being treated for severe burns and other critical injuries at Massachusetts General Hospital in Boston.)

Firefighting runs in the family, and maybe that shouldn’t be a surprise. After all, firefighting is itself an ad hoc family united in shared purpose and sacrifice.

From Kittery to Fort Kent, Maine firefighters share something in common that is instantly recognizable when they come together, as they often do for conferences, training and at fire scenes.

Many of those firefighters lined the streets to honor Capt. Bell as his body was taken first from the scene of the explosion to the state Medical Examiner’s Office in Augusta, then back to a funeral home in Farmington.

In Maine, most firefighters are volunteers. All must be prepared to answer a call when it comes. It becomes a way of life not only for firefighters but also their families at home, who watch them leave at all hours, wondering if they’ll be safe.

Usually they are. But sometimes they are not — and the entire firefighting family feels it.