The time for summoning before administrative detention is 24 hours.
 Article 83 of the Law of the People's Republic of China on Administrative Penalties for Public Security shall, after being summoned by the public security organ, promptly inquire and verify those who violate the administration of public security, and the time for inquiry and verification shall not exceed eight hours; If the circumstances are complicated and administrative detention punishment may be applied according to the provisions of this Law, the time for inquiry and verification shall not exceed 24 hours. The public security organ shall promptly notify the family members of the person summoned of the reason for the summons and the place of the summons.
 Summon procedure: (I) In the process of fire law enforcement, if it is necessary to summon, the law enforcement personnel shall fill in the Summon Certificate and submit it to the leader for approval, and then issue the Summon Certificate. （2） The law enforcement personnel shall serve the Summon Certificate on the summoned person according to law; The summoned person shall sign or seal on the receipt of the Summon Certificate and indicate the date of receipt. （3） If the summoned person refuses to accept the summons or evades the summons without justified reasons, compulsory summons shall be implemented according to law with the approval of the leader. （4） After being summoned to the case, the summoned person shall conduct interrogation and verification in a timely manner, and make interrogation records. Each interrogation shall not exceed 24 hours. （5） In case of any violation of relevant laws and regulations found on the spot, the handling personnel can summon the relevant personnel orally. When an oral summons is announced, the undertakers shall explain the reasons for the summons and record the situation of the oral summons in the transcript during the interrogation.
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 Legal basis
 Article 83 of the Law of the People's Republic of China on Administrative Penalties for Public Security shall, after being summoned by the public security organ, promptly inquire and verify those who violate the administration of public security, and the time for inquiry and verification shall not exceed eight hours; If the circumstances are complicated and administrative detention punishment may be applied according to the provisions of this Law, the time for inquiry and verification shall not exceed 24 hours.
 The public security organ shall promptly notify the family members of the person summoned of the reason for the summons and the place of the summons.