N.H. Rev. Stat. Ann. § 541-A:19-b

An agency may adopt a form as defined in RSA 541-A:1, VII-a, either by incorporating the actual form by reference in a rule, or by setting forth the requirements of the form in rules, adopted according to the procedures in this chapter and in compliance with the drafting and procedure manual pursuant to RSA 541-A:8. No new or amended form shall be effective and enforceable pursuant to RSA 541-A:22, I unless the form has been adopted in accordance with this chapter.