Environnement MP101M, Technical Manual

Page: 14 / 196

Environnement
S.A
MP101M
Duplication prohibited
SEPTEMBER 2013
0–14
SAFETY GUIDELINES
0.5 RISK ANALYSES
The equivalents of maximum permissible dose laid down by French regulations are given in the here-below
table. The values are extracted from the public health laws (Labour and Public Health Rules).
According to the French labour laws, a worker is told exposed if, because of his professional activity, he is
submitted to ionizing radiations likely to involve doses superior to the levels presented here-below.
Exposed zone Limit of equivalent dose
Global exposure 1 mSv/ year
Crystalline lens 15 mSv/ year
Skin 50 mSv/ year in average value for any surface of 1cm²
0.5.1 EXTERNAL EXPOSURE
When the analyzer is working, and even when the analyzer is not working, there is no direct access to the
source. Under normal conditions of analyzers use, there is no possible irradiation. Indeed, because of the
radiation type, there is no possible external exposure for the whole body (radiations have a distance lower than
23cm).
Consequently, the sources handling only occur when the source is put in place into the analyzer, and when
the source is put out of the analyzer at the end of the source use.
The sources handling can only be carried out by people qualified and trained to this kind of sources and to
their specific dangers. The technician must wear gloves.
For hands, in contact with the window of measurement, we can consider a dose rate of 0, 1µSv/h. To exceed the
regulatory threshold of 50000µSv per year, the technician should leave his hands in contact with the window of
measurement of the analyzer during more than 500 000 hours per year, which is realistic. Therefore, the values
are very much lower than flows of tolerable for the public.
NOTA : to value the received dose, the dosimetric films are inoperative because insensitive to Beta
radiations of low energy.
0.5.2 INTERNAL EXPOSURE
The internal exposure corresponds to the ingestion or the inhalation of radioactive materials.
According to the appendices of directive Euratom 96/29, the effective dose engaged by ingestion for the 14C
is 5,8.10
-10
Sv/Bq. To exceed the threshold of 1 mSv/an (total exposure), it would be necessary to eat one
14
C source per year (for source of 1,6MBq)
These situations are obviously completely improbable. In normal condition of use the probability of inhaling
radioactive dusts is very low: the sources are sealed into a closed analyzer.
Assessments by French Radioprotection Expert, IRSN, was made, they confirmed that the level of internal
exposure is considered negligible and radiation doses are well below regulatory limits.
In normal use, the personnel, using MP101M, is not defined as exposed worker, and is not classified
into category A or B. The acceptable exposure values are those valid for the public.
In practice, there is neither protected area (it would be located in contact with the outlet window which is
inaccessible), nor controlled area.