The Model 901 Key Chain Radiation Detector for Upper-Range Radiation is an effective and easy to use system for detecting dangerous levels of radiation.

More than just a radiation detector, the NukAlert™ is a patented personal radiation meter, monitor and alarm. Small enough to attach to a key chain, the device operates non-stop, 24/7 and will promptly warn you of the presence of unseen, but acutely dangerous levels of radiation.

Used nationwide by federal, state and local first responders, law enforcement and the Dept. of Defense, the device is the ideal solution for increasing individual security and awareness of radiological threats. It will be very reassuring to know, with confidence, when you and your family are out of the worst danger.


  • Tested & Verified by Naval Air Warfare Center
  • Always "ON" 24/7, Includes long-life 10+ year battery
  • Detection Range: 100 mR/hr to 5,000 R/hr,
  • Metering: 100 mR/hr to 50 R/hr, in 10 calibrated ranges
  • Proportional Increasing Chirp Rate: 50 R/hr to 5,000 R/hr
  • Gamma and X-rays from 20 keV to above 2 MeV
  • Sensitivity incl. higher emergency radiation levels
  • Alarm "chirp" corresponds to chart on back of device
  • Introduced before Health Physics Society - 1/03
  • Performance verified by Nat'l Radiological Laboratory
  • Each unit individually radiation accuracy tested
  • Patented technology
  • Made in the U.S.A.
Why Berkeley Nucleonics ?

We provide live online consulting at live-help, we stock these units, and we build it into a program with our Isotope Identifiers, Personal Radiation Detectors and Training Programs. BNC as been around since 1963 providing radiation detection products for First Responders, Hazmat Units, Military, etc.


Detects Gamma & X-ray radiation 20 keV to 2+ MeV
Detection Range 100 mR/hr to 5,000 R/hr
Sensitivity 100 mR/hr to 50 R/hr indicated in 10 ranges
Proportional Increasing Chirp Rate 50 R/hr to 5,000 R/hr
Indication Repeating groups of rapid countable chirps
Operational indicator Faint "ticking"= operating OK
Alarm loudness 61 dBA (speaking volume)
Durability Functional after 6' drop or submersion to 6'
Battery Operational Life Expectancy @ room temp
Non-alarming (normal operation)- 10 to 15 years
Alarming continuously at single shirp level - 3 year
Alarming continuously at highest alarm level - 3 months
See NEW Battery Replacement Program
Detector Patented CdS photo resistor coupled to a rare earth phosphor scintillator
Housing Hermetically sealed, radiation transparent, abrasion resistant ABS plastic
Accuracy Within /- 1 chirp
Response Time Does rate dependant
~3-4 min. @ 100mr/hr
seconds @ R/hr ranges
Accumulated dose chart on back EMP Immunity
Meets MIL-STD-461D, RS 105
Over range survivability Functional after 5K R/hr for 2 hr
Temperature Range -20C to +50C
Physical 1.75"x1.25"x.75"H (LxWxH), Wt

Technical resources: 

PDF icon 901-manual.pdf86.18 KB
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