Neutron radiation detectors containing non-pressurized boron trifluoride gas may be transported under this entry provided that:

a) radiation detectors containing in excess of 1 gram of boron trifluoride and radiation detection systems containing such neutron radiation detectors as components may be transported on cargo aircraft in accordance with all applicable requirements of these Instructions irrespective of the indication of "forbidden" in columns 12 and 13 of Table 3-1, provided the following conditions are met:

 i) each radiation detector must meet the following conditions.

  1) the pressure in each detector must not exceed 105 kPa absolute at 20 °C;

  2) the amount of gas must not exceed 13 grams per detector;

  3) each detector must be manufactured under a registered quality assurance programme;

      Note: The application of ISO 9001:2008 may be considered acceptable for this purpose.

  4) each neutron radiation detector must be of welded metal construction with brazed metal to ceramic feed through assemblies. These detectors must have a minimum burst pressure of 1 800 kPa as demonstrated by design type qualification testing; and

  5) Each detector must be tested to a 1 x 10-10 cm³/s leaktightness standard before filling.

 ii) Radiation detectors transported as individual components must be transported as follows:

  1) they must be packed in a sealed intermediate plastics liner with sufficient absorbent material to absorb or adsorbent material to absorb or adsorb the entire gas contents;

  2) they must be packed in strong outer packagings and the completed package must be capable of withstanding a 1.8 m drop test without leakage of gas contents from detectors; and

  3) The total amount of gas from all detectors per outer packaging must not exceed 52 g.

 iii) completed neutron radiation detection systems containing detectors meeting the conditions of sub-paragraph i) must be transported as follows:

  1) the detectors must be housed in a strong sealed outer casing;

  2) the casing must contain sufficient absorbent or adsorbent material to absorb or adsorb the entire gas contents; and

  3) the completed systems must be packed in strong outer packagings capable of withstanding a 1.8 m drop test without leakage unless a system's outer casing affords equivalent protection.

 iv) each package must bear a "Toxic gas" and "Corrosive" hazard label irrespective of no labels being indicated in column 5;

 v) transport in accordance with this special provision must be noted on the dangerous goods transport document. A packing instruction must not be shown on the transport document.

  If the above conditions are met, the requirements of Special Provision A2 do not apply.

b) neutron radiation detectors containing not more than 1 gram of boron trifluoride, including those with solder glass joints, and radiation detection systems containing such detectors are not subject to these Instructions when carried as cargo, provided they the following conditions are met:

 i) each radiation detector must meet the requirements in sub-paragraph a) i) and be packed in accordance with sub-paragraph a) ii);

 ii) radiation detection systems containing such detectors must be packed in accordance with sub-paragraph a) iii); and

 iii) the words "not restricted" and the special provision number A190 must be provided on the air waybill when an air waybill is used.

If the above conditions are met, the requirements of Special Provision A2 do not apply.