BDT – Bubble Detector Thermal


Overview

Bubble detectors are the most sensitive, accurate, neutron dosimeters available and have been 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.

Health physicists and others who are especially concerned with thermal neutron dose can take advantage of the simplicity and low cost of thermal neutron bubble detectors. The BDT bubble detector is preferentially sensitive to thermalized neutrons, with an exclusion ratio of thermal-to-fast neutron response exceeding 10:1.

Notes: Thermal: fast neutron sensitivity > 10:1

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 Thermal (~ 1/V for epithermals)
  • Dose Range 0.1 - 10 mrem; 1.1 - 112 μSv
  • Sensitivity Range 20 - 40 bubbles/mrem; 1.8 - 3.6 bubbles/μSv
  • Automatic Temperature Range 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

Resources

Data Sheets