Bydd y system Rhybuddion Argyfwng yn cael ei defnyddio i rybuddio pobl os bydd argyfwng lle mae bygythiad sylweddol i fywyd. Anfonir Rhybuddion Argyfwng i bob ffôn symudol cydweddol o fewn ardal benodol o risg.
The Emergency Alerts system will be used to warn people in the event of emergencies where there is a significant threat to life. Emergency Alerts are sent to all compatible mobile phones within a specific area of risk.