N.H. Rev. Stat. Ann. § 4:13-m

In recognition of the service given by the men and women who, night and day, serve the people of this state as firefighters, and inviting the governments, communities, and people of this state to observe such day with appropriate ceremonies and activities, the governor shall proclaim the last Saturday or Sunday in September of each year as Firefighters Memorial Day in honor of the firefighters who have been killed or disabled in the line of duty and those still serving.