Warning system

Warning system is any system of biological or technical nature deployed by an individual or group to inform of a future danger. Its purpose is to enable the deployer of the warning system to prepare for the danger and act accordingly to mitigate or avoid it.

A HSS Engineering TWS 295 electronic sirens warning Civil Defense siren.
There are 8,200 alarm sirens for civil protection throughout Switzerland. They are tested once a year, on the first Wednesday in February.[1] About this soundSound sample 
Warning light indicating danger of laser exposure

Warnings cannot be effective unless people react to them. People are more likely to ignore a system that regularly produces false warnings (the cry-wolf effect), but reducing the number of false warnings generally also increases the risk of not giving a warning when it is needed.[2] Some warnings are non-specific: for instance, the probability of an earthquake of a certain magnitude in a certain area over the next decade. Such warnings cannot be used to guide short-term precautions such as evacuation. Opportunities to take long-term precautions, such as better building codes and disaster preparedness, may be ignored.[3][better source needed]

Early warning siren for earthquakes and floods

Biological warning systemsEdit

Man-made warning systemsEdit

Civilian warning systemsEdit

 
A fire alarm that warns people if a building is on fire

Military warning systemsEdit

Historical beacon-based systems:

Space-based missile early warning systems:

Airborne early warning systems:

Ground-based early warning radar systems:

Optical sensors:

Emergency broadcasting:

See alsoEdit

Notes and referencesEdit

  1. ^ Testing sirens, Swiss Federal Office for Civil Protection (page visited on 7 September 2013).
  2. ^ Sättele, Martina; Bründl, Michael; Straub, Daniel (October 2015). "Reliability and effectiveness of early warning systems for natural hazards: Concept and application to debris flow warning" (PDF). Reliability Engineering & System Safety. 142: 192–202. doi:10.1016/j.ress.2015.05.003. ISSN 0951-8320. Retrieved 2018-02-07.
  3. ^ https://www.theguardian.com/science/blog/2012/may/30/attempts-predict-earthquakes-harm-good
  4. ^ [1] Archived December 12, 2006, at the Wayback Machine