I. The driver of any vehicle shall obey the instructions of any traffic control device applicable thereto placed as provided by law, unless otherwise directed by a traffic or police officer, subject to the exceptions granted the driver of an authorized emergency vehicle in this chapter.
II. No provision of this chapter for which signs are required shall be enforced against an alleged violator if at the time and place of the alleged violation an official sign is not in proper position and sufficiently legible to be seen by an ordinarily observant person.

Terms Used In New Hampshire Revised Statutes 265:9


III. Whenever traffic control devices are placed in position approximately conforming to the requirements of this chapter, such devices shall be presumed to have been so placed by the official act or direction of lawful authority, unless the contrary shall be established by competent evidence.
IV. Any traffic control device placed pursuant to the provisions of this chapter and purporting to conform to the lawful requirements pertaining to such devices shall be presumed to comply with the requirements of this chapter, unless the contrary shall be established by competent evidence.
V. When a traffic control device is not operational, the driver shall obey the rules of the road applicable to intersections without traffic control devices or intersections with 4-way stop signs, including, but not limited to:
(a) Yielding the right of way to a vehicle on the right, N.H. Rev. Stat. § 265:28, I.
(b) Vehicle turning left yielding to approaching vehicle, N.H. Rev. Stat. § 265:29.
(c) Yielding to vehicle which has entered the intersection, N.H. Rev. Stat. § 265:30, I.
(d) Yielding by vehicle entering from private roadway or driveway, N.H. Rev. Stat. § 265:32.
(e) Yielding to emergency vehicles, N.H. Rev. Stat. § 265:33.
(f) Yielding to pedestrians in crosswalks, N.H. Rev. Stat. § 265:35.