The app on chemical and biological risks are mainly a consultative and didactic, while the app risk radioactive contains an application that allows you to calculate - in connection with an intensity of any source placed at a certain distance, the values ​​of which are measured on field - the safety distance or time or the dose of exposure to workers and the general public in accordance with the levels established by law. These are estimates for comparison, that is based on the physical property of proportionality between the intensity and the squares of the distances, there is no need to know the type of radioactive source, but the assessment is based only on the reading of the instruments and the equipment (radiametro and rangefinder) .