| Main Title |
Variability of I/M Test Scores over Time. |
| Author |
Smith., L. R. ;
|
| CORP Author |
Southwest Research Inst., San Antonio, TX.;Environmental Protection Agency, Ann Arbor, MI. Emission Control Technology Div. |
| Publisher |
Sep 88 |
| Year Published |
1988 |
| Report Number |
EPA-68-03-4044; EPA/460/3-88/008; |
| Stock Number |
PB90-235714 |
| Additional Subjects |
Exhaust emissions ;
Time series analysis ;
Concentration(Composition) ;
Hydrocarbons ;
Carbon monoxide ;
Tables(Data) ;
Air pollution sampling ;
Motor vehicle inspection ;
Motor vehicle maintenance ;
Emission factors
|
| Holdings |
| Library |
Call Number |
Additional Info |
Location |
Last
Modified |
Checkout
Status |
| NTIS |
PB90-235714 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
| Collation |
213p |
| Abstract |
The program involved conducting twice-weekly I/M (Inspection and Maintenance) emission short tests on twenty-five late model gasoline-fueled vehicles over a 15-week time period. All of the twenty-five vehicles (1981 model year or later) were tested once in the morning and again later that same day following a soak period of at least three hours. The vehicles tested in the program were owned by Southwest Research Institute employees and were selected to represent a variety of vehicle types, emission controls, etc. Emission tests were conducted using two Bear Automotive Type 42-925 4-Gas Infrared Analyzers with generic software. Each emission test sequence included a 'Test Analyzer Specifications' ('TAS') sequence (i.e., 2500 rpm/idle test with emissions measured in both modes), a vehicle conditioning step utilizing three minutes of engine operation at 2500 + or - 300 rpm with the vehicle transmission in neutral, idling in neutral for 15 seconds, and finally a second TAS sequence. The tests were conducted to provide EPA with information regarding variability in short test emission results, impact of off-idle no-load preconditioning cycles on short test emissions, and emission differences between a fully-warmed vehicle and a 'soaked' vehicle having undergone minimum operation. Hydrocarbon and carbon monoxide emissions are reported for each vehicle in tabular and graphical form. Hydrocarbons are reported in ppm and carbon monoxide in percent. |
| Supplementary Notes |
Sponsored by Environmental Protection Agency, Ann Arbor, MI. Emission Control Technology Div. |
| Category Codes |
68A |
| NTIS Prices |
PC A10/MF A02 |
| Primary Description |
200/05 |
| Document Type |
NT |
| Cataloging Source |
NTIS/MT |
| Control Number |
022222818 |
| Origin |
NTIS |
| Type |
CAT |
