N.H. Rev. Stat. § 265-A:4
Any person who drives, operates, or attempts to operate an OHRV, drives or attempts to drive a vehicle upon the ways of this state, or operates or attempts to operate a boat upon the public waters of the state shall be deemed to have given consent to physical tests and examinations for the purpose of determining whether such person is under the influence of intoxicating liquor or controlled drugs, prescription drugs, over-the-counter drugs, or any other chemical substances, natural or synthetic, which impair a person's ability to drive and to a chemical, infrared molecular absorption, or liquid or gas chromatograph test or tests of any or all of any combination of the following: blood, urine, or breath, for the purpose of determining the controlled drug, prescription drug, over-the-counter drug, or any other chemical substance, natural or synthetic, which impairs a person's ability to drive content of such person's blood or alcohol concentration if arrested for any offense arising out of acts alleged to have been committed while the person was driving, operating, attempting to operate, or in actual physical control of an OHRV, driving, attempting to drive, or in actual physical control of a vehicle, or operating, attempting to operate, or in actual physical control of a boat while under the influence of intoxicating liquor or controlled drugs, prescription drugs, over-the-counter drugs, or any other chemical substances, natural or synthetic, which impair a person's ability to drive or while having an alcohol concentration in excess of the statutory limits contained in RSA 265-A:2 or RSA 265-A:3. The test or tests shall be administered at the direction of a law enforcement officer, peace officer, or authorized agent having reasonable grounds to believe the person to have been driving, operating, attempting to operate, or in actual physical control of an OHRV, driving or in actual physical control of a vehicle, or operating or in actual physical control of a boat while under the influence of intoxicating liquor or controlled drugs, prescription drugs, over-the-counter drugs, or any other chemical substances, natural or synthetic, which impair a person's ability to drive or while having an alcohol concentration of 0.08 or more, or in the case of a person under the age of 21, 0.02 or more. A copy of the report of any such test shall be furnished by the law enforcement agency to the person tested within 48 hours of receipt of the report by the agency by certified mail directed to the address shown on such person's license or other identification furnished by the person. Results of a test of the breath shall be furnished immediately in writing to the person tested by the certified breath testing operator conducting the test. When the incident involves an accident resulting in death or serious bodily injury to any person as provided in RSA 265-A:16, the prerequisites of RSA 265-A:8 shall not apply. Properly trained personnel of the United States Coast Guard may arrest and conduct tests on persons who are believed to be under the influence of intoxicating liquor or controlled drugs, prescription drugs, over-the-counter drugs, or any other chemical substances, natural or synthetic, which impair a person's ability to drive or a combination thereof, and who are in physical control of a boat operating upon the public coastal waters of this state.
RSA 265-A:4
2006, 260:1. 2012, 267:4, eff. Jan. 1, 2013. 2017, 78:2, eff. July 1, 2017.