If there is any change of address for a registered electrical worker, the Electrical and Mechanical Services Department (EMSD) should be informed as early as possible through one of the following means -

• Use the EMSD online service (password and personal e-cert are required); or
• Complete the form “ Notification of Changing Address by Registered Electrical Worker” (ER42A, PDF), and return to EMSD using one of the following methods –
  • In person to the EMSD Registration and Permit Office, or drop the application into the drop-in box located in EMSD HQs
  • By post to the EMSD Registration and Permit Office
  • Use the Change of Address Service on GovHK

Electrical and Mechanical Services Department Customer Services Office
Address: G/F, Electrical and Mechanical Services Department Headquarters, 3 Kai Shing Street, Kowloon Bay
Office hours:

• Monday to Friday: 9:00am to 5:15pm (open during lunch hours); closed on Saturday, Sunday and Public Holidays
• Saturday: 8:30am to 12:30pm (drop-in box located at G/F lobby only)