• Adopt the 60 – 60 Rule: Listen at no more than 60% of the mobile device's maximum volume for less than cumulative 60 minutes a day. Prolonged use of earphones should be avoided to prevent accumulative noise induced damage.
  
• Sound with sudden rise and fall of noise level e.g. shooting, hammer, and firecracker in video games (Impulse sound) and sound of noise level change drastically over time, e.g. road traffic noise, rock music (fluctuating sound) are more damaging than continuous noise with the same sound level. Adjust the output to a lower volume setting for music / game / film that include impulse and fluctuating sound.

• Use the built-in "smart volume" feature which help to regulate the volume and cap the possible maximum output in the products, if available.

• Avoid using mobile electronic screen products while doing other tasks requiring attention e.g. crossing the roads, etc.

• Pay attention to personal hygiene, clean the surface of the screen regularly and avoid sharing the electronic screen products with others.

• Adjust brightness, font size and workstation.
  
  A. Eyes should be slightly above the top of the screen and no less than 50 cm from the screen.
  
  B. Sit upright and close to the desk.
  
  C. Forearms should be approximately horizontal and supported by the desk. A space in front of the keyboard to allow hands and wrists to rest when not typing.
  
  D. Keep wrists straight when keying.
  
  E. Position a mouse within easy reach so it can be used with a straight wrist.
  
  F. Legs should have rooms to move under the desk.
  
  G. Choosing a chair with round edge or curved cushion seat can avoid excess pressure from the edge of seat on the backs of legs and knees. A footrest may be helpful.
  
  
• 30 - 40 - 50: Keep reading distance no less than 50 cm for computers, 40 cm for tablet PCs and 30 cm for smartphones.
  

The following suggestions on screen time for children and adolescents are recommended.

• 1) Pre-schoolers:

• 1.1) Under 2 years old: Your child needs a large amount of parent-child interaction before two years old. Avoid letting him in contact with any electronic screen products unless to do interactive video-chat with family members under parents’ guidance. If you think the use of certain screen activity may benefit his learning and development, always accompany and guide him and set limits for him.

• 1.2) 2 to 5 years old: The daily accumulated time for your child to watch TV or use computer, tablet computer or smartphone should be restricted to within one hour. The screen activities should be interactive and educative, and to be carried out under your guidance.

• 2) Primary school students (6 to 12 years old): Limit recreational screen time to no more than two hours a day. Set rules to help children build up time management skills.

• 3) Secondary school students (12 to 18 years old): Adolescents should be trained to develop good time management skills and self-discipline to work independently and prepare themselves to be responsible adults. Regular breaks should be adopted if prolonged screen time e.g. for academic purpose, is unavoidable.

• Children and adolescents should avoid gossiping, harassing or flaming others with mean or scornful messages that would harm other’s reputation or relationship with friends or family. They should be respectful and polite online and avoid sending mean messages or making someone look bad, which may remain in the Internet for a very long time with damages out of imaginations.

• Once starting to use the Internet, children should be taught to protect their privacy and avoid exposing too much personal information.

• Children should be shown and learn how to set password and not to share with others, except parents, if it is found necessary.

• Children and adolescents should not meet a “friend” only known online.

• Children and adolescents should not respond to messages or photos that make them feel uncomfortable or scared, and they should report the incidents to parents or teachers and seek their help.
  

• Parents should frequently monitor the content, websites and activities that their children engage.

• Parents should choose age-appropriate video games for their children.

• Install software for cyber-safety (e.g. filtering software) to limit access to inappropriate content, websites or other activities.
  

• Play time and talking between children and parents, especially for younger children, is encouraged for emotional bonding and social development.

• Group activities are encouraged for development of social and communication skills as well as emotional management.

• Parents and teachers are encouraged to appreciate and acknowledge the importance of non-academic achievements in the holistic development of children and adolescents.
  

• Consecutive use for more than one hour of Internet and other electronic screen products including smartphones, tablet personal computers, video games, or televisions is discouraged.

• Physical activities, including outdoor activities, are encouraged:

  1) Pre-schoolers: Accumulate at least three hours physical activities daily.

  a) Under 2 years old: Parents can give more opportunities for motor activities by allowing toddlers to run and walk instead of being carried or riding in a baby stroller.

  b) 2 to 6 years old: Parents and teachers should encourage children and adolescents to have play (preferably outdoor), stretching, aerobic, muscle strengthening and group activities daily. At home, light intensity activities (e.g. playing with toys, dressing up, packing school bags, etc.) on top of more vigorous ones (e.g. brisk walking, riding tricycle, playing hide-and-seek, etc.) are the range of activities good for young children's health and growth.

  2) Primary and secondary school students (6 to 18 years old): Accumulate at least 1 hour of moderate-to vigorous-intensity physical activity daily.

  a) Moderate-intensity physical activity e.g. swimming, cycling or playing volleyball.

  b) Vigorous-intensity physical activity e.g. playing basketball, football or rope skipping.

  

• Rest for 20 to 30 seconds after every 20 to 30 minutes when using electronic screen products.
  
• Change position, blink eyes and do muscle relaxation exercise.
  
  1) Keep back and neck straight with elbow supported
  
  2) Keep palm up and stretch wrist downward
  
  3) Stretch fingers backward
  
  4) Circle shoulder blade backward
  
  5) Tuck chin in
  
  6) Stretch neck sideway
  
  7) Stretch chest wall
  
  Source : Hong Kong Physiotherapy Association

• Adequate sleep time is essential for health. Babies and toddlers need two to three short naps in the daytime while 3 to 5 years old may need at most one daytime nap.

• Total amount of sleep in a day is different for different age groups:
  
  1) Newborns (up to 2 months): 12 to 18 hours
  
  2) Infants (2 to 12 months) 13 to 15 hours
  
  3) Toddlers 1 to 3 years old: 12 to 13 hours
  
  4) 3 to 5 years old: 11 to 13 hours
  
  5) 5 to 12 years old: 9 to 11 hours
  
  6) 12 to 18 years old: 8.5 to 9.5 hours

• Encourage a quiet, dim and comfortable sleeping place. Turn off the computer and keep other electronic screen products out of reach during sleep.

• Establish a soothing pre-sleep routine with a period of relaxing activities an hour or so before bed, e.g. take a bath, read a book, avoid stressful and stimulating activities such as video game playing as well as vigorous exercises.