Taipei, May 12 (CNA) Taiwan's Central Epidemic Command Center (CECC) has announced a four-level system of COVID-19 alerts, each with defining criteria and a set of prevention measures to be imposed in response.

Taiwan is currently at a Level 2 alert, but Health Minister Chen Shih-chung (陳時中) said Wednesday that the alert level could be raised to 3 "in the coming days" depending on how the situation develops.

Below are the CECC's COVID-19 alert standards and response measures:

Level 1

•Criteria: Imported cases resulting in isolated community transmission.

•Masks must be worn at all times on public transportation and in crowded public venues.

•The CECC recommends the cancellation or postponement of non-essential gatherings that will bring people into close contact with others.

•Places of business and public venues must implement an identification-based registration system, social distancing, temperature checks, and routine disinfection.

Level 2

•Criteria: Domestically transmitted cases from unknown sources.

•Fines imposed for failure to follow mask guidelines.

•Cancellation of outdoor gatherings of 500+ people and indoor gatherings of 100+ people.

•Public gatherings must implement social distancing, mask-wearing/partitions, an identification-based registration system, temperature checks, crowd controls and routine disinfection or be cancelled.

•Places of business must impose crowd controls; those unable to implement necessary epidemic prevention measures should temporarily suspend operations.

•When necessary, the CECC may order the closure of entertainment or leisure-related businesses or public venues.

Level 3

•Criteria: Three community clusters within a week (or) ten domestically transmitted cases from unknown sources in one day.

•Masks must be worn at all times outdoors.

•Cancellation of outdoor gatherings of 10+ people and indoor gatherings of 5+ people.

•Apart from essential services, law enforcement, medical treatment and government, all places of business and public venues must close.

•At places of business or public venues that remain open, mask wearing and social distancing is required.

•In neighborhoods where community transmission has occurred, residents must stay within defined a perimeter and comply with COVID-19 testing. All public gatherings and school classes within the neighborhoods are suspended.

Level 4

•Criteria: Sharp increase in domestic cases (a daily average of above 100 cases over the last 14 days) with at least half transmitted from unknown sources.

•Leave home only for essential activities (to purchase food, receive medical treatment, or for essential work); observe social distancing and wear a mask at all times outdoors.

•When at home, wear a mask (or) maintain social distancing.

•All public events cancelled: Apart from essential services, law enforcement, medical and government services, all in-person work and school is suspended.

•Lockdown imposed in townships, counties or cities where the outbreak is severe. Only designated personnel may enter/exit the lockdown area; residents must remain in their homes.

*Level of alert may be adjusted at the discretion of the CECC