ASN Report 2017

54 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 01  - Nuclear activities: ionising radiation and health and environmental risks in place for several decades. This system is primarily based on the mandatory wearing of a passive dosimeter by workers liable to be exposed and it is used to check compliance with the regulation limits applicable to workers: these limits concern, on the one hand, the total exposure (since 2003, the annual limit, expressed in terms of effective dose, has been 20 mSv for 12 consecutive months), obtained by adding the dose due to external exposure to that resulting from any internal contamination; other limits, called equivalent dose limits, are defined for the external exposure of certain parts of the body such as the hands and the lens of the eye (see chapter 3). The recorded data allow the identification of the cumulative exposure dose for a given period (month or quarter) for each person working in nuclear facilities, including workers from subcontractor companies. They are grouped together in Siseri (Ionizing radiation exposure monitoring information system) managed by IRSN and are published annually. The monitoring system does not include worker exposure to radon. For each sector, Tables 1 and 2 give the breakdown into the populations monitored, the collective dose and the number of times the annual limit of 20 mSv was exceeded. They clearly show a significant disparity in the breakdown of doses depending on the sector. For example, the medical and veterinary activities sector, which comprises a significant share of the population monitored (nearly two thirds of the total), in fact only accounts for about 25% of the collective dose, the nuclear industry however, which represents about 20% of the headcount, accounts for more than 45% of the collective dose. The industrial sector, which represents just 10% of the headcount, accounts for 28% of the collective dose. The latest statistics show a slight but regular increase in the number of persons subject to dosimetric monitoring since 2005 (see Diagram 2); the mark of 350,000 individuals was exceeded in 2012. This trend is largely due to the increase in the number of persons monitored in the fields of medical and veterinary activities. After a slight decrease in 2013, for the first time since 2001, the years 2014, 2015 and 2016 again show a slight increase in the number of persons monitored. At the same time, the overall collective annual dose has decreased (by about 50% since 1996, whereas the number of people monitored has increased by about 60%). The collective dose did however display an upward trend between 2006 and 2009, followed by a levelling off over the 2009-2012 period. After a singular increase in 2013, the collective dose for (63.2 man.Sv in 2016) has since 2015 returned to values similar to those observed over the 2009-2012 period. The number of monitored workers whose annual dose exceeded 20 mSv has fallen since 2015; only one case exceeding the effective annual dose was observed in 2106 (effective dose of 65.2 mSv for a worker in the non-destructive testing sector) (see Diagram 3). With regard to the dosimetry of the extremities (fingers and wrist), 28,672 workers were monitored in 2016 (i.e. 7.7% of the total number of persons monitored). Out of all the persons monitored, there were two cases where the 500 mSv regulatory equivalent dose limit at the extremities was exceeded (568 mSv and 800 mSv for two workers in the medical imaging sector). For the second year running, data relative to monitoring of the lens of the eye are available. Four thousand four hundred NUMBER OF PERSONS MONITORED COLLECTIVE DOSE (man-Sv*) INDIVIDUAL DOSE > 20 mSv Reactors and energy production (EDF) 25,483 7.83 0 Fuel cycle; decommissioning 7,690 2.25 0 Transport 853 0.12 0 Logistics and maintenance (contractors) 15,574 11.15 0 Effluent, waste 84 0 0 Others 20,725 6.75 0 TABLE 1: Monitoring of external exposure of nuclear workers (year 2016) Source: IRSN * Man.Sv: Unit of quantity of collective dose. For information, the collective dose is the sum of the individual doses received by a given group of persons. NUMBER OF PERSONS MONITORED COLLECTIVE DOSE (man-Sv*) INDIVIDUAL DOSE > 20 mSv Medecine 129,541 11.43 0 Dental 51,238 2.13 0 Veterinary 21,490 0.6 0 Industry 38,127 17.8 1 Research 11,635 0.41 0 Miscellaneous 25,711 1.36 0 TABLE 2: Monitoring of external exposure of workers in small-scale nuclear activities (year 2016) Source: IRSN * Man.Sv: Unit of quantity of collective dose. For information, the collective dose is the sum of the individual doses received by a given group of persons.