Assisted living centers are rare in Mass, but many families still don’t know what they offer — or what they don’t.

All 273 assisted living facilities in Massachusetts must send letters to all residents and families detailing fire safety protocols, evacuation procedures and key points of contact, the state announced Friday.

The Fall River mayor’s office has confirmed all Gabriel House residents displaced by the tragic Sunday fire that claimed nine lives now have new living arrangements.

The family of a resident at the Gabriel House assisted living facility has retained a law firm to investigate the circumstances leading up to the deadly Sunday fire that killed nine people and left dozens injured.

There’s no doubt in my mind that that fire was destined to kill 50-plus people,” Fall River Fire Chief Jeffrey Bacon said Wednesday.

FALL RIVER — The nine residents killed in a fire here at Gabriel House, an assisted living residence, are being remembered as fonts of knowledge and symbols of longevity.