BD-PND – Personal Neutron Dosimeter


Bubble detectors are the most sensitive, accurate, neutron dosimeters available. Used for over 25 years by nuclear facilities, research institutes, military personnel, and the medical community, bubble detectors provide instant visible detection and measurement of neutron dose. Inside the detector, tiny droplets of superheated liquid are dispersed throughout a clear polymer. When a neutron strikes a droplet, the droplet immediately vaporizes, forming a visible gas bubble trapped in the gel. The number of bubbles provides a direct measurement of the tissue-equivalent neutron dose.

The bubble detector is the only neutron dosimeter where the response is independent of dose rate and energy, with zero sensitivity to gamma radiation. Bubble detectors are so compact, lightweight, and rugged, that they can be clipped to a coat or shirt pocket, placed in areas with limited access, or used in close proximity to a neutron source for a quick assessment. With an isotropic angular response, neutron dose can be accurately measured regardless of the direction of neutrons relative to the detector. Bubble detectors are ideal for ALARA programs, providing the user with an immediate measurement of neutron hazards.

The BD-PND is the recommended detector for personal neutron dosimetry. Its sensitivity exceeds the ICRP-60 requirements for neutron dosimetry. It incorporates automatic compensation for sensitivity change with temperature over the operational range of 20 – 37 °C. Nuclear laboratories, utilities, and military personnel have found that the BD-PND’s immediate visual response and high sensitivity, coupled with its small size, light weight and rugged construction, make it the ideal device for ALARA programs.

Notes: Recommended for personal neutron dosimetry

All bubble detectors offer:

  • Zero gamma sensitivity
  • Energy-independent above threshold, dose rate-independent, tissue-equivalent dose measurements
  • Isotropic angular response
  • 90 day warranty

Technical Specifications

  • Energy Range < 200 keV to > 15 MeV
  • Dose Range 0.1 - 500 mrem, 1 - 5350 µSv
  • Sensitivity Range (Low) 1 - 2 bubbles/mrem, 0.093 - 0.19 bubbles/µSv
  • Sensitivity Range (Medium) 10 - 19 bubbles/mrem, 0.94 - 1.8 bubbles/µSv
  • Sensitivity Range (High) 20 - 40 bubbles/mrem, 1.9 - 3.7 bubbles/µSv
  • Automatic Temperature Compensation Yes
  • Optimum Temperature Range 20 - 37 °C
  • Size 145 mm length x 19 mm diameter
  • Weight 58 g
  • Re-Use Yes
  • Recompression Method Integrated Assembly