In Hong Kong, each year among the elderly aged 65 and over, has about one in five people will have a fall. Among 75% will be injured, including head trauma and fractures. Elders who have fallen in the past six months, the risk of falling in the next few months will be higher than others.

Fall is preventable, it is not an inevitable process of aging. In fact, there are no device can ensure the person will not fall, however an alarm is very useful by alerting the caregiver that the patient is ‘getting up’ from a bed or chair. The