Nucleonic Corporation of America Film Badge (ca. 1960)

NCA film dosimeter

This film badge was produced by the Nucleonic Corporation of America (NCA) sometime around 1960. The estimated date of 1960 is based on the fact that this particular design was pictured and described in an advertisement in the July 1959 issue of the journal Health Physics. NCA had been using a different badge design in 1957 (Nucleonics 1957). The company also produced wrist and ring film badges.

To facilitate change outs of the film packets, the badge employs a hinged cover. By pushing the tab at the bottom, the badge is easily opened. Other badge designs often made it very difficult to change the film packets. 

The badge usually employed a film packet that contained both a high and low sensitivity piece of film in a paper wrapper—the wrapper filtered out betas below 300 keV. Three metal filters were used to account for the film's energy dependence: two of copper and one of lead.

Beta calibrations were performed using uranyl nitrate. Either a cadmium or lead absorber was used to flatten out the film’s over-response near 100 keV. This particular example used lead along with copper. Calibrations for gamma rays were performed using Ra-226 and Co-60 sources at 50 mR to 500 R. Calibrations for X-rays were performed with 25 to 200 kvp X-rays. For neutron measurements, NCA used Eastman NTA film calibrated with a Ra-Be source.

NCA film dosimeter open

As NCA stated in a 1959 advertisement: 

“To the Health Physicist falls the critical and complex task of evaluating the hazards in radioactive areas and of selecting a plan to counteract these hazards. To the supplier of a Film Badge Service falls the task of developing the specialized skills and tools necessary to reliably support this plan and provide for its implementation. Two partners . . . both vitally concerned with leaving nothing to chance in protecting the human machine.”

Size: 1.5" x 2"

Weight: 1 oz

Donated by Ron Kathren.

References

  • Nucleonics February 1957, p 111.
  • Health Physics, July 1959, p.iii.