Accreditation and standards

Our entire manufacturing and measuring process is organized on the basis of a quality assurance system that complies with the requirements of the following standards :

• ISO/IEC 17025, General Requirements for the Competence of Testing and Calibration Laboratories
• ISO/EN 9001, Model for Quality Assurance in Design, Development, Production, Installation and Servicing.
• NF/EN 46001, Medical devices : specific requirements concerning the application of standard ISO/EN 9001.

With respect to medical products, LEA takes account of Directive 93/42/EEC in obtaining EU approval.

Note : this is not an exhaustive list.

COFRAC accreditation validates the following aspects:

• technical capabilities,
  
• impartiality,
  
• calibration methods,
  
• traceability,
  
• quality system. 

CE Approval

In accordance with Directive 93/42/EEC concerning medical devices, LEA's products are CE approved under the following classification:

• class I (flood sources),
• class II b (calibration sources for PET, pen point markers, radioactive rulers and wire sources).

Compliance with national and international codes and standards

Quality is based on compliance with the national and international codes and standards listed in the table below.

Standard/Regulations	Subject	Level
Public Health Regulations	Laws, decrees and statutory texts	National
Decree n° 2002-460 of 04/04/2002	Concerning the general protection of people against ionising radiation risks	National
ISO 17025	General requirements for the competence of testing and calibration laboratories	International
COFRAC COmité FRançais d'ACcréditation	French Accreditation Committee Ionising radiation calibration	National
ISO 9001	Design, production and measurement	International
93/42/CEE	EU approval for medical devices	International
EN 46001	Supplement to ISO 9001 concerning medical devices	International
NF M61-002	Definition of sealed sources	National
ISO 2919	Definition of sealed sources	International
ISO 8769	Calibration	International
NF ISO 9978 (classification index M61-003)	Leaktightness of sealed sources	International
ISO 1677	Checks/tests : Non contamination Dimensional Leak tests	International
French authorities	Transport	National
ADR European agreement on international carriage by road	Road transport	European
IAEA International Atomic Energy Agency	Transport	International
ICAO International air transport regulations	Transport	International

Traceability

The traceability of radioactive materials and – in certain cases – components is assured throughout the production process. It is this traceability that defines LEA's relationships with all of the national and international bodies that possess measurement standards within a hierarchical chain.

The International Vocabulary of Basic and General Terms in Metrology (VIM) defines traceability as follows : (the) “property of the result of a measurement or the value of a standard whereby it can be related to stated references, usually national or international standards, through an unbroken chain of comparisons all having stated uncertainties.”

VIM states in a footnote that “the unbroken chain of comparisons is called the linkage-to-standards chain or the calibration chain« and that »the way in which the link to the standards is made is known as linkage to standards”.

Measurements

Depending on the type of standard concerned, the measuring instruments used are based on thefollowing techniques :

• well-type ionization chamber (beta, gamma),
• grid ionisation chamber (alpha),
• thin-window 2 pi proportional counters,
• 4 pi proportional counters (beta ou alpha),
• proportional counters (standard gases),
• liquid scintillation counters (beta ou alpha),
• ZnS scintillators with specified solid angle (alpha),
• NaI(TI) scintillators (gamma, standard gases),
• Ge-HP solid-state detectors (gamma, X),
• Si semiconductors with surface barriers (alpha).

As part of its COFRAC accreditation, LEA complies with the requirements of standard ISO/IEC 17025 concerning management of measuring instruments. Key aspects of measuring instrument management include :

• management of measuring links with the national primary standards laboratory (LNHB),
• determination and improvement of LEA's measuring uncertainties through participation in interlaboratory test programs,
• tracking of drift through regular monitoring of calibration,
• maintenance of LEA's measuring processes,
• monitoring of ambient conditions.

Tests

Sealed sources have to comply with standards ISO 2919 and NF M61-002 to qualify as sealed sources following specific tests (impact resistance, puncture, etc.).
Sources are tested according to the methods specified in standards ISO 1677, ISO/TR 4826 and
NF ISO 9978 :

• non-contamination (wipe) test,
• leak test:

• cold immersion test
• hot immersion test
• bubble immersion test
• helium leak test

Wipe test (non-contamination test)
All the external surfaces of the sources are wiped using filter paper soaked in a non-corrosive solvent.
The total activity on the filter paper is then measured. If it is less than 185 Bq, the source is considered to be non-contaminated. Different leak test methods can be used for sealed sources depending on the type of source.

Cold immersion test
The source is immersed in water at 50°C for four hours. It is then removed from the water, and the total activity of the liquid is measured. If the activity is less than 185 Bq, the source is considered to be leaktight.

Hot immersion test
The source is immersed in 5% nitric acid (1 part nitric acid with a density of 1.33 g/cm3 to 19 parts distilled water). The solution is boiled for ten minutes. The source is then rinsed using fresh solution. The operation is repeated twice, using the liquid from the previous rinse. The source is removed, and the activity of the liquid is measured. If it is less than 185 Bq, the source is considered to be leaktight.

Bubble immersion test
The source is immersed for three minutes, either in ethanol at ambient temperature (with the pressure above the liquid being reduced), or in water at 90°C (at atmospheric pressure). No bubbles must be observed.

Helium leak test
The source is placed inside a pressure tube. The air is removed from the tube by purging with helium, and the tube is pressurized for a period of 30 minutes. The tube is then depressurized, and the source transferred to a vacuum chamber. The leakrate is measured under vacuum conditions. If it is less than 10-8 cm3.s-1, the source is considered to be leaktight.

Under French law, standard solid sources are generally subjected to non-contamination (wipe) testing. However, given the required metrological quality, and in view of the fragile, low-active nature of some standards, this test is not carried out, as it could affect the sources and impair their accuracy.

Calibration certificates

All standards are supplied with a calibration certificate, which provides precise information on the measurement method used, the impurity content (where applicable), and the degree of uncertainty. It states :

• the radionuclide,
• the atomic number
• the half-life of the radionuclide
• the activity level and its uncertainty at a given date,
• the particle flux within a specified solid angle,
• uniformity of emission (for flood sources for medical use).

In addition, all sources are accompanied by the following instructions:

• procedure to be followed on receipt of the source,
• instructions for use.

The user must retain the certificate throughout the period during which the product is held.
The certificate will be requested during the return-ofsource procedure.