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Motorists in Line at the Safety Lane at an Auto Emission Inspection Station in Downtown Cincinnati, Ohio. Safety Inspection of All Vehicles Began in 1940 and Was Made on a Semi-Annual Basis until January, 1975, When They Became an Annual Event.
All Vehicles Still Must Pass the Safety Check. However, All Light Duty, Spark Ignition Powered Motor Vehicles Also Must Be Monitored for Carbon Monoxide and Hydrocarbon Emissions by an Exhaust Analyzer 09/1975. Photographer: Eiler, Lyntha Scott. Original public domain image from Flickr
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