The conditions for registered dental hygienists in Hong Kong are as follows:

1. Education requirements: Hold a dental hygiene diploma, degree or certificate issued by the Hong Kong Registered Dental College or other recognized dental colleges.

2. Internship experience requirements: complete at least one year of full-time work or two years of part-time work, and obtain a qualified internship evaluation.

3. Professional examination: Take and pass the examination organized by the Dental Council of Hong Kong.

4. On-the-job training: Participate in and pass training courses approved by the Dental Affairs Council.

5. Health status: in good health and in compliance with relevant health requirements.