N.H. Rev. Stat. § 21-P:12-c

I. Any person who is a state certified fire instructor employed by a nonprofit fire department or emergency medical service unit shall be immune from civil liability in any action brought on the basis of any act or omission during training which results in damage or injury to any person if: (a) The instructor had prior written approval from the division, to teach a curriculum approved by the fire standards and training commission; (b) The instructor was acting in good faith and within the scope of the instructor's official functions and duties as an instructor; and (c) The damage or injury was not caused by willful, wanton, or grossly negligent misconduct by the instructor. II. In this section: (a) "Damage or injury" includes physical, nonphysical, economic and noneconomic damage and property damage. (b) "Nonprofit fire department" shall include, but not be limited to, not for profit fire service organizations exempt from taxation under section 501(c) of the Internal Revenue Code of 1986 organized or incorporated in this state. (c) "State certified fire instructor" means a person who has completed the requirements to hold such certification as approved by the New Hampshire fire standards and training commission.