California Code, Code of Civil Procedure - CCP § 1822.56

An inspection pursuant to this warrant may not be made between 6:00 p.m. of any day and 8:00 a.m. of the succeeding day, nor in the absence of an owner or occupant of the particular place, dwelling, structure, premises, or vehicle unless specifically authorized by the judge upon a showing that such authority is reasonably necessary to effectuate the purpose of the regulation being enforced. An inspection pursuant to a warrant shall not be made by means of forcible entry, except that the judge may expressly authorize a forcible entry where facts are shown sufficient to create a reasonable suspicion of a violation of a state or local law or regulation relating to building, fire, safety, plumbing, electrical, health, labor, or zoning, which, if such violation existed, would be an immediate threat to health or safety, or where facts are shown establishing that reasonable attempts to serve a previous warrant have been unsuccessful. Where prior consent has been sought and refused, notice that a warrant has been issued must be given at least 24 hours before the warrant is executed, unless the judge finds that immediate execution is reasonably necessary in the circumstances shown.