(a) A complaint initiating an action pursuant to this chapter shall be personally served and notice to all in personam defendants shall be provided in the same manner as serving complaints in civil actions. Where the in personam defendant is an owner or landlord, notice shall also be served by leaving a copy of the complaint at the landlord’s address as set forth in the lease or as otherwise provided by landlord with an adult person residing therein, or with an agent or other person in the employ of the owner or landlord whose responsibility it is to accept such notice. If the owner or landlord is an artificial entity pursuant to Supreme Court Rule 57, service of the notice or process may be made by leaving a copy thereof at its office or place of business as set forth in the lease with an agent authorized by appointment or by law to receive service of process. Where the in personam defendant is a tenant, notice shall also be served by leaving a copy of the complaint at the person’s rental unit or usual place of abode with an adult person residing therein. After filing an affidavit that personal service cannot be had after due diligence on 1 or more in personam defendants, within 20 days after the filing of the complaint, the plaintiff may serve a copy of the complaint by registered or certified mail or first class mail as evidenced by a certificate of mailing postage-prepaid, addressed to the owner or landlord at the owner or landlord’s business address as set forth in the lease or as otherwise provided by the owner or landlord, or if the owner or landlord is an artificial entity, pursuant to Supreme Court Rule 57, at its office or place of business, or if the defendant is a tenant, to said tenant at the leased premises. The return receipt of the notice, whether signed, refused or unclaimed, sent by registered or certified mail, or the certificate of mailing if sent by first class mail, shall be held and considered to be prima facie evidence of the service of the notice or process. The plaintiff shall also cause a copy of the complaint to be affixed conspicuously to the premises alleged to be the site of a nuisance. Service shall be deemed completed 5 days after filing with the court proof of such mailing and an affidavit that a copy of the complaint has been affixed to the premises.

(b) All tenants or residents of any premises which is used in whole or in part as a business, home, residence or dwelling, other than transient guests of a guest house, hotel, or motel, who may be affected by any order issued pursuant to this chapter shall be provided such reasonable notice as shall be ordered by the court and shall be afforded opportunity to be heard at all hearings.

72 Del. Laws, c. 484, § 1.