Batch sampling involves collecting and storing emissions for later analysis. Examples of batch sampling include collecting and storing gaseous emissions in a bag or collecting and storing PM on a filter. You may use batch sampling to store emissions that have been diluted at least once in some way, such as with CVS, PFD, or BMD. You may use batch sampling to store undiluted emissions. You may stop emission sampling anytime the engine is turned off, consistent with good engineering judgment. This is intended to allow for higher concentrations of dilute exhaust gases and more accurate measurements. Account for exhaust transport delay in the sampling system and integrate over the actual sampling duration when determining ndexh. Use good engineering judgment to add dilution air to fill bags up to minimum read volumes, as needed.
TABLE 1 of § 1065.170 -CONTAINER MATERIALS FOR GASEOUS BATCH SAMPLING
Emissions | Engine type | |
Compression-ignition Two-stroke spark-ignition Four-stroke spark-ignition at or below 19 kW | All other engines | |
CO, CO2, O2, CH4, C2 H6, C3 H8, NO, NO2, N2 O | TedlarTM, KynarTM, TeflonTM, or 300 series stainless steel | TedlarTM, KynarTM, TeflonTM, or 300 series stainless steel. |
THC, NMHC | TeflonTM or 300 series stainless steel | TedlarTM, KynarTM, TeflonTM, or 300 series stainless steel. |
40 C.F.R. §1065.170