Shakealarm (original) (raw)

ShakeAlarm is an on-site earthquake early warning system (EEWS) developed by Weir-Jones Engineering Consultants in Vancouver, British Columbia. The system functions by detecting and identifying fast moving P-waves that arrive before the slower and damaging S-waves generated from the hypocenter of an earthquake. Once ShakeAlarm has identified a candidate P-wave it will determine in less than 500 milliseconds if the following S-wave will be strong enough to be dangerous. Once the determination has been reached that an inbound S-wave might exceed acceptable levels the system can trigger the structured shutdown of critical processes - gas, electricity and water services - and can also be used for opening of fire bay doors, SMS warnings to the general population and a variety of other services