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Motorist Gets in Line for the Safety Lane at an Auto Emission Inspection Station in Downtown Cincinnati, Ohio. Inspections Began in 1940 and Were Made on a Semi-Annual Basis until January, 1975 When They Became an Annual Event.
In Addition to the Safety Check All Light Duty, Spark Ignition Powered Motor Vehicles Are Hooked Up to an Exhaust Analyzer and Monitored for Carbon Monoxide and Hydrocarbon Emissions. All Such Vehicles in Hamilton County Must Be Inspected 09/1975. Photographer: Eiler, Lyntha Scott. Original public domain image from Flickr
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