RSA 595-B:4: Duration.

An inspection warrant shall be returned to the court to which it is made returnable as soon as it has been executed, and in any event not later than 7 days from the date of its issuance, unless extended or renewed by the justice, associate justice, or special justice who signed and issued the original warrant, upon satisfying himself that such extension or renewal is in the public interest. An inspection warrant shall be executed and returned to the person by whom it was issued within the time specified in the warrant or within the extended or renewed time. After the expiration of such time, the warrant, unless executed, shall be void.