nuclear-chicago Radiation Detector


Accession Number: 2016.zoo.2.1-3

Instrument Name: nuclear-chicago Radiation Detector


The D34 thin-window Geiger-Muller tube radiation detector (2016.zoo.2.1) is a black plastic cylinder with a sticker on its anterior circular face that is partially rubbed off. This face of the cylinder is also a cap that can be removed to reveal a glass face through which a needle-like object inside of the cylinder can be viewed. On its anterior, there is a four-pronged plug. There is a red and white sticker on the curved face of the cylinder that shows the brand of the object, its type, serial number, DC operating volt, and the marking: “MICA”. On the curved face of the cylinder, posterior to the sticker, there are white markings which read “BdO *4F 27.” The object is packaged in a white, red, and black rectangular cardboard box that is labelled, “RADIATION DETECTOR,” and the address “333 EAST HOWARD AVENUE DESPLAINES, ILLINOIS” is labelled onto another rectangular face of the box.

The container of counting planchets (2016.zoo.2.2) is a clear plastic cylinder that is slightly yellowed. It has been labeled “NUCLEAR-CHICAGO” in black print on white labels that circle the periphery of the object twice at both the bottom and top of the object. Inside the cylinder, 60 circular aluminum planchets are stacked on top of each other. The planchets are all separate pieces and are removable from the cylindrical container.

The model T1 Dual Timer (2016.zoo.2.3) is a light grey metal cube with a dial on one of its faces. The cube also has a black rubber cord that is attached to its posterior that culminates in a plug-like metal connector, inside which are 2 larger prongs surrounded by 7 smaller prongs. The “connector” has an movable metal circular part around it and is embossed with the word “AMPHENOL” once on both the movable and stable parts. The dial on the front of the object is surrounded by a rounded square metal plaque. On the plaque, “nuclear-chicago” is labeled in the top right corner, and “DUAL TIMER” is labeled under the centre of the dial. From the centre of the dial outward, there are four different series of numbers that circle its periphery. The series closest to the dial comprises red numbers that count from 0-55 in increments of 5. The second series is printed in black and counts from 55 to 5 in increments of 5. The next series, located outside the movable part of the dial, is printed in black and counts from .10 to .90 in increments of 10 and the outermost number series is printed in red and counts from .90 to .10 in increments of 10. There is an on/off switch on the bottom right corner of the plaque. The dial only moves one full rotation to the right and one full rotation to the left.

Primary Materials:

Plastic, Cardboard, Aluminum, Metal, Rubber


Plug: “CAUTION This Cap…ave…Usin…etector…DO…OUCH”, “LICENSED ONLY TO EXTENT INDICATED ON CARTON”, “nuclear-chicago”, “RADIATION COUNTER”, “TYPE 000033″, “SERIAL 65-47″, “DC OPERATING VOLT 900″, “MICA 3.5 MG/CM”, “MADE IN U S A”, “BdO *4F 27″

“NUCLEAR-CHICAGO”, “Made in U.S.A”, “CLEARSITE”, “1373″, “NEWARK, N.J”

“nuclear-chicago”, “DUAL TIMER”, “ON”, “OFF”, “8420 MOD.”, “4006 SER.”, “DEPLAINES ILLINOIS”, “MADE IN U.S.A.”, “AMPHENOL”

Dimensions (cm):

Box: Height: 4.5, Width: 4.5, Length: 20.5, Plug: Length: 11, Diameter: 3.6, Cylinder: Length 17.7, Diameter: 3.6, Cube: Height: 13, Width: 13, Length: 13


The D34 geiger-muller tube for radiation detection was used alongside a 250kVp x-ray unit. The x-ray unit was used to deliver high doses of radiation to plants and mammals and the radiation detector was used to measure the response of ions to the radiation exposure. The thin-window, or mica sheet, on the end of the detector, was designed to allow lower energy radiation (beta particles) to enter the cylinder of the instrument and to catalyze a response between radioisotopes and particles.

The counting planchets were used to weigh biological samples that had been exposed to radiation.

The T1 dual timer was used with a scaler unit (machine that counts the effects of radiation over a time period), to count radioisotopes (unstable atoms that emit nuclear energy). The timer would be set to begin counting at a predetermined time and this would also trigger the scaler unit to begin counting radioisotopes. When the timer was finished counting down, the scaler would also stop and would provide the researcher with a measurement of radioisotopes based on the amount of particles per. time value.


Good condition. Plastic of cylinder is slightly yellowed. There is dust on the top face of the cube which could also be dirt stuck to the residue from a former sticker.

Manufacturer: nuclear-chicago corporation

Date of Manufacture: 1963?


These instruments were used by Professor Gordon Clark who was a leading expert on the effects of radiation, and conducted research in a radiation facility, (now a storage area for the Department of Ecology and Evolutionary Biology), in the basement of Ramsey-Wright Laboratory at University of Toronto.

As detailed by one of Professor Clark’s former students, Dr. Clark was focused on the effects of low-dose radiation on mammalian systems and used radiation detection instruments in his own work, and for student’s experiments. Dr. Clark mainly experimented on mice and rats however, he also collaborated with Dr. Chandorkar: a Botany professor; to study the effects of radiation on plant systems.

Dr. Clark used the counting planchets (zoo.2016.2.2) in his experiments to weigh excised tissue and organs from rats and mice. The planchets were typically used to weigh tissues from the mammals’ spleens and thymus’. Tissue from these organs would be weighed twice using the planchets: once right after they were excised from the animal, and again once they were dried out.

Additional Information and References:

“nuclear-chicago.” (n.d.). National Radiation Instrument Catalog. Retrieved from

nuclear-chicago. (1953). “Catalog M.” Nuclear Instrument and Chemical Corporation.

nuclear-chicago. (1957). “Catalog Q.” Nuclear-Chicago Corporation.

Wikipedia. (2016). “Radionuclide.” Retrieved from

Wikipedia. (2016). “Survey Meter”. Retrieved from

Donated to UTSIC: Yes