Document ID: chunk:federal_register_of_legislation:F2012C00283:reg:11:p2
Version: federal_register_of_legislation:F2012C00283
Segment Type: reg
Provision Reference: reg 11 (pt 2/7)
Character Range: 451753–454595

shall be drawn through all these data points. This calculation shall not take into account the test results at 0 km.
               The data will be acceptable for use in the calculation of the deterioration factor only if the interpolated 6,400 km and 160,000 km points on this line are within the above mentioned limits.
               The data are still acceptable when a best fit straight line crosses an applicable limit with a negative slope (the 6,400 km interpolated point is higher than the 160,000 km interpolated point) but the 160,000 km actual data point is below the limit.
               A multiplicative exhaust emission deterioration factor shall be calculated for each pollutant as follows:

Where:

Mi1     =  mass emission of the pollutant i in g/km interpolated to 6,400 km,

Mi2     =  mass emission of the pollutant i in g/km interpolated to 160,000 km.

               These interpolated values shall be carried out to a minimum of four places to the right of the decimal point before dividing one by the other to determine the deterioration factor. The result shall be rounded to three places to the right of the decimal point.
               If a deterioration factor is less than one, it is deemed to be equal to one.

                At the request of a manufacturer, an additive exhaust emission deterioration factor shall be calculated for each pollutant as follows:

          D . E . F . = Mi2 – Mi1

Annex 9 - Appendix 1
  Standard Bench Cycle (SBC)
              1. Introduction
               The standard ageing durability procedure consists of ageing a catalyst/oxygen sensor system on an ageing bench which follows the standard bench cycle (SBC) described in this Appendix. The SBC requires the use of an ageing bench with an engine as the source of feed gas for the catalyst. The SBC is a 60-second cycle which is repeated as necessary on the ageing bench to conduct ageing for the required period of time. The SBC is defined based on the catalyst temperature, engine air/fuel (A/F) ratio, and the amount of secondary air injection which is added in front of the first catalyst.
              2. Catalyst Temperature Control
              2.1. Catalyst temperature shall be measured in the catalyst bed at the location where the highest temperature occurs in the hottest catalyst. Alternatively, the feed gas temperature may be measured and converted to catalyst bed temperature using a linear transform calculated from correlation data collected on the catalyst design and ageing bench to be used in the ageing process.
              2.2. Control the catalyst temperature at stoichiometric operation (01 to 40 seconds on the cycle) to a minimum of 800 °C (±10° C) by selecting the appropriate engine speed, load, and spark timing for the engine. Control the maximum catalyst temperature that occurs