Gerald R. Ford was president. Median household income was $11,800. Gas cost 57 cents a gallon. And NRC inspectors, as part of the Independent Measurements Program, routinely hit the road in a fully equipped van containing a mobile laboratory. Inspectors measured samples of radioactive effluents from nuclear power plants, checking on the accuracy of sampling routinely done by the plants’ own laboratories.
The image directly above on the left shows an NRC inspector placing a liquid radioactive waste sample in a cryogenic detector for analysis of its isotopic composition. In the image directly above on the right, an NRC inspector reviews analytical data. A similar van, but with portable equipment, was used to verify measurements during safeguards inspections of materials facilities. During a safeguards inspection, the equipment was removed from the van and carried inside the facility for use.
Images from the 1975 U.S. Nuclear Regulatory Commission Annual Report
U.S. NRC Blog 
These vintage multi channel analysers, running on vacuum tube electronics- I remember those for counting betas and grammas- one sample at a time. They were work horses of 70s did a remarkable jobs of counting effluent samples, if they met Appendix-B limits and daily discharge of 25 millicuries at that time. Definitely nostalgic Intruments. Wonder when they were replaced by Beckman counters, capable of counting assembly lines of samples of modern era.
Carl J Papperillo running the lab.