Abstract: On August 17, 2006, Employee #1 was working with a work crew assigned to harvest and pack table grapes in the vineyard of Peterson Ranch, in Cantua Creek, California. The crew was working approximately 100 yards east and southeast of a field being sprayed with sulfuric acid as a soil amendment and conditioner. The acid was sprayed at a rate of two tons per acre, in large droplets at 10 psi and 2 mph, with spray nozzles approximately 6 in. above ground. Employee #1 and coworkers from the work crew complained of dizziness, headache, and shortness of breath. All workers went home by noon and none of them sought medical attention, even though they were given the opportunity to do so. Employee #1 was not hospitalized. The Fresno County Environmental Health Division took wipe samples of the grape leaves and packing equipment and tested them with Ph paper to determine surface residue from the sulfuric acid over-spray. Their analytical results were negative for any acidity value below a Ph of 7.0.