The auto-ranging 451B measures radiation rate and accumulated dose from beta, gamma and x-ray radiation sources. The 451B’s site surveying capabilities make it well-suited for a wide range of end users, including: police and fire departments, x-ray manufacturers, government agencies, state inspectors, emergency response and HAZMAT teams, nuclear medicine labs, hospital radiation safety officers, and nuclear power workers. The ion chamber detector allows for a fast response time to radiation from leakage, scatter beams and pinholes. Additionally, the low noise chamber bias supply provides for fast background settling time. A sliding beta shield serves as an equilibrium thickness for photon measurements and enables beta discrimination. The digital display features an analog bar graph, 2.5 digit digital readout, low battery and freeze (“peak hold”) mode indicators, and an automatic backlight function. User controls consist of an ON/OFF button and a MODE button. The case is constructed of lightweight, high strength materials and is sealed against moisture. The RS-232 interface can be connected directly to a computer for use with the Excel add-in for Windows (451EXL), enhancing the functionality of the instrument. This software allows for data retrieval, user parameter selection and provides a virtual instrument display with audible (requires sound card) and visual alarm indication.

• High sensitivity measurement of rate and dose simultaneously, with the capability to record peak rate
• Auto-ranging and auto-zeroing
• RS-232 communications interface with optional Windows-based Excel add-in for data logging
• Ergonomic, anti-fatique handle with replaceable grip, wrist strap and tripod mount
• Programmable flashing LCD display and audible alarm
• Easily-accessible battery door (operated by 2 9-volt alkaline batteries) on the outside of the bottom case
• Available with dose equivalent energy response (SI units)
• CE Tested. Meets applicable standards

• 451B-RYR Ion Chamber Survey Meter with Beta Slide and standard chamber 
• 451B-DE-SI-RYR Ion Chamber Survey Meter with Beta Slide and dose equivalent chamber