The terrorist attacks of 11 September 2001 in New York and the explosion of the AZF plant in Toulouse on 21 September 2001 led the authorities to envisage disaster scenarios which could occur anywhere in the country, with large numbers of injured (from several hundred to several thousand). In the case of a nuclear or radiological accident, a significant percentage of these injured could be contaminated by radionuclides, posing specific care and treatment problems for the emergency response teams.

Circular 800 of 23 April 2003 specifies the national policy concerning the use of emergency and care resources in the event of a terrorist act involving radioactive materials. The methodology described in this interministerial document does not aim to replace the generic procedures contained in the plans currently in force, in particular the government's PIRATOME plan, but more to guide the services and organisations in charge of planning and managing emergency situations.

Together with the Hospitalisation and Health Care Directorate (DHOS) of the Ministry for Health, the services of the Defence High Official (HFD) of the Ministry for Health, the specialists of the Paris SAMU (emergency medical service), the armed forces radiological protection service (SPRA), the IRSN, CEA, EDF and universities, the ASN drew up a series of primary response sheets called the "Medical response to a nuclear or radiological event". This document contains all useful information needed by front-line medical personnel responsible for collecting and transporting the injured, as well as by hospital personnel who will be receiving them in the nearby hospital facilities. This guide acts as a teaching aid for the medical emergency professionals national training programme set up by the Ministry for Health and the French SAMU emergency medical service.

The "Medical response to a nuclear or radiological event" file comes in addition to circular 2002/277 of 2 May 2002 concerning the organisation of medical care in the case of a nuclear or radiological accident. This circular is supplemented by circular 2002/284 of 3 May 2002 concerning the organisation of the hospital system in the event of arrival of large numbers of victims, setting up a departmental plan of hospital capacity provisions and a zone-based organisation for all nuclear and radiological, but also biological and chemical hazards. The "Medical response to a nuclear or radiological event" file is currently being revised to take account of the new zone-based organisation and offer improved support for the medical personnel training sessions involving practical work currently being deployed nationally.

In 2005, jointly with the Hospitalisation and Health Care Directorate (DHOS) and the General Directorate for Health (DGS) at the Ministry for Health, the ASN took part in the visits organised by the Defence High Official (HFD) to the various defence areas, in order to identify any difficulties and the procedures for implementing these arrangements.

In 2005, the ASN was contacted via its radiological emergency hot-line, through its on-call staff or directly by those in charge of the dossiers, with regard to events such as triggering of detection portals (customs posts, technical landfills), discovery of unidentified sources during an inventory (hospital, high school), or even theft of sources. Even if they entail no health risk, these events warrant verification and radioactivity measurements.

In December 2005, in its capacity as competent national authority under the terms of the 30 November directive mentioned above, the ASN was contacted with regard to the gammagraphy accident that occurred in Chile (see box).