‘Radiation Alert Monitor 4’ radiation detector

Made by SE International Inc in Summertown, Lawrence county, Tennessee, United States, North and Central America, 1990-2005.

These various radiation meters were originally procured and/or used by the NSW government agencies including the former State Pollution Control Commission (SPCC), the Environment Protection Authority (EPA), the NSW Department of Environment and Conservation (DEC), and possibly the NSW Department of Health. These agencies, collectively over the years regulated the use of radiation apparatus (for example x-ray machines used in medical diagnostics) and radioactive substances (for example cobalt-60 ...


Object No.


Physical Description

Radiation detector in a small handheld black plastic case. The front of the machine has two switches and a meter in the readout screen. The scale in the readout screen has 0-5µ Sv/hr (sieverts per hour) in the upper scale and 0-0.5 mR/hr (rem) in the lower scale. The range switch consists of three settings: x1, x10, and x100. The whole unit has a leather carry case.



160 mm


90 mm


50 mm


178 g



Radiation detector made by SE International Inc in Summertown, Tennessee, United States of America, between 1990-2005.

SE International Inc is a small manufacturer of radiation detection equipment for use in industrial, governmental, educational, medical, and environmental markets. They have been producing radiation alert equipment since 1970.

The Monitor 4 radiation detector is a compact general purpose survey meter capable of detecting alpha, beta, gamma, and X-rays over 3 selectable ranges. The monitor senses ionizing radiation by means of a GM (Geiger Mueller) tube with a thin mica window. The tube is closed inside the instrument. When a ray or particle of ionizing radiation enters or passes through the tube, it is sensed electronically and displayed by a red light count. When the switch is in the AUDIO position, the instrument will also beep with each radiation event, about 5 to 25 counts at random intervals (depending on your location and altitude) can be expected every minute from naturally occurring background radiation.


SE International Inc 1990-2005


Credit Line

Gift of the Department of Environment and Conservation New South Wales, 2007

Acquisition Date

5 June, 2007

Cite this Object


'Radiation Alert Monitor 4' radiation detector 2016, Museum of Applied Arts & Sciences, accessed 21 January 2018, <https://ma.as/365721>


{{cite web |url=https://ma.as/365721 |title='Radiation Alert Monitor 4' radiation detector |author=Museum of Applied Arts & Sciences |access-date=21 January 2018 |publisher=Museum of Applied Arts & Sciences, Australia}}

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