The available vehicular aldehyde studies were summarized in an attempt to characterize aldehyde emissions from motor vehicles. Topics covered in these studies include aldehyde emission factors for unmodified and malfunction vehicle engine configurations, effects of fuel, mileage accumulation and temperature variations and aldehyde emissions from Diesel-equipped vehicles equipped with prototype light-duty Diesel oxidation catalysts. Thus, it was possible to obtain aldehyde data for standard conditions and for a variety of operating conditions. The Federal test procedure (FTP) was used for the light-duty vehicles and the 13-mode test procedure for the heavy-duty engines. The 2, 4 dinitrophenylhydrazine (DNPH) procedure was used for the sampling and analysis of the aldehydes. This procedure is discussed in the Appendix. In addition to aldehydes, the DNPH procedure detects two ketones, methylethylketone and acetone. Methylethylketone measurements are not included in this report. However, acetone and two aldehydes, acrolein and propionaldehyde are reported together as acetone since they are not resolved from each other under normal gas chromatographic operating conditions. The term 'total aldehydes', as used in this report, includes the acetone measurements.

Includes bibliographical references (pages 16-17). "May 1981." Cover title. "EPA/AA/CTAB/PA/81-11."