Keleket K-700 and Unknown Model Indirect Reading Pocket Chambers (late 1940s/early 1950s)

The following photograph shows a Model K-700 indirect-reading pocket chamber manufactured by the Kelley-Koett Manufacturing Company of Covington Kentucky sometime around 1950—it is identified as a K-700 on the cap used to protect the charging contact at the bottom end (left in photo) of the chamber. The manufacturer's literature states that "it is used for monitoring personnel exposed to X- or Gamma radiation. Before being used it is charged on the Keleket Charge-Reader, Model K-425. It is worn on the person throughout the entire period of exposure. When the Pocket Chamber is inserted into the Charge-Reader, the total amount of X- or Gamma radiation to which the Pocket Chamber has been exposed will be indicated on the scale of the Charge-Reader microscope. When used with the Keleket Charge-Reader, total radiation up to 200mr can be measured."

Keleket K700

From 80 keV to 250 keV, the K-700 can exhibit an over-response of up to 20%. Its response is essentially energy independent from 250 keV to 3,000 keV.

Keleket K700

I have been unable to determine anything about the Keleket indirect-reading pocket dosimeter shown in the following photograph. It differs from the K-700 in two obvious ways: the metal pocket clip is not painted and the protective cap is aluminum rather than bakelite as was the case with the K-700. My guess is that it is of more recent vintage than the dosimeter shown above. It might well be a later version of the K-700 (later versions did have an aluminum protective cap).

Size: 4 5/8” long and 0.5” in diameter

Weight: 0.5 oz.


  • Atomic Energy Commission. Radiation Instrument Catalog Catalog No. 2. Part 2. 1950 page PIC-2E, page date May 1, 1950.
  • Advertisement, Nucleonics March 1954, page 94.
  • Keleket Bulletin Q-3, no date.
  • Keleket Price List, February 1, 1950.