In order for his license or certificate to be operative, any person licensed as a private security services business under subsection A of § 9.1-139 or certified as a private security services training school under subsection B of § 9.1-139 shall file with the Department evidence of a policy of liability insurance in an amount and with coverage as fixed by the Department. The liability insurance shall be maintained for so long as the licensee or certificate holder is licensed or certified by the Department. Every personal protection specialist and private investigator who has been issued a registration by the Department and is hired as an independent contractor by a licensed private security services business shall maintain comprehensive general liability insurance in a reasonable amount to be fixed by the Department, evidence of which shall be provided to the private security services business prior to the hiring of such independent contractor pursuant to subsection C of § 9.1-139.