SPEDIapp is a free Web App which allows to determine the effects of possible accidents taking place within industrial plants. Such accidents might involve the release of toxic substances as well as fires or explosions. The algorithms implemented in the app are based on the guidelines published within the Italian law D.P.C.M. 25 February 2005 (Planning of external emergencies for industrial plants).

SPEDIapp guides the user to determine the possible accidental event by a series of consecutive and inter related selections. The only quantitative information that the user must know, or estimate, is the amount of substance involved in the accident.

The effects of an accident usually decrease increasing the distance from the point where the accident has originated. The areas of damage can be considered as circles for explosions and fires, and as circular sectors with amplitude of 36 degrees and directed as the wind for toxic releases. The radius of each circle or circular sector is calculated by SPEDIapp.

The distance of severe impact defines an area of possible high lethality.

The distance of damage defines an area where possible serious and irreversible injuries might happen to people without suitable protections.

The distance of attention defines the area where possible minor damages might happen, particularly for vulnerable people (for example elderly or children). This distance is not determined by SPEDIapp however, as a rule of thumb, it may be assumed equal to the distance of damage.

The meteorological conditions are described by two classes: D5 (Pasquill Gifford stability class D and wind speed of 5 m/s) and F2 (Pasquill Gifford stability class F and wind speed of 2 m/s). Not all the accidents require the specification of a meteorological condition.


SPEDIapp is a web app developed for iPad. SPEDIapp should work even on Android based tablet, however it has not been tested yet on such devices. Once installed, SPEDIapp will work even without an internet connection, therefore it can be used "on field" to get a first estimation of the effects of an accident..

In order to install SPEDIapp on your iPAD, follow these simple instructions:

  1. Open this link in Safari on your iPad, you will see the app as a web page.
  2. Tap on the plus (+) sign at the bottom of mobile Safari and choose "Add to Home Screen".
  3. SPEDIapp is now installed as an offline app, you can use it without the internet connection.
SPEDIapp example mask

You may also be intereseted in SPEDI a Windows application that lets you easily apply the expeditious method for the identification of risk areas in the External Emergency Planning (EEP) of industrial plants with Major Accident Risk. The methodology is based on the contents of Annex 1 of the Italian Decree of February 25, 2005. SPEDI can be used by the operators of the field belonging to the prefectures, regions and local authorities and Civil Protection dealing with emergency planning in the context of industrial risk management, as well as the operators of the establishments at risk of major accident for which there is a duty of preparing the EEP.

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