1. Inter-laboratory comparison exercise cpc calibration material: 2nd stage
Focus on soot as harmonized calibration material for Automotive PN counters.
Generators: Various miniCAST & Palas DNP
Goal: The calibration uncertainty of “best practice” soot calibration
Apply Lessons Learned from first round:
Focus on Counting Efficiency
Validate DMA
Traveling flow meter
Less tests
Only two CPCs: 1 reference, 1 device under test
Standardized data collection
Terres: CPC Calibration Round Robin | Proposal of second stage |

2. Inter-laboratory comparison exercise cpc calibration material: 2nd stage
Basic procedure:
Calibration of circulated EE CPC (D50=23nm) against circulated reference CPC (D50=10nm) with in-house CAST/Palas soot generator
Counting efficiency curve, focus on 23nm and 41nm. Possible extras: 10/15/70nm
same set-up variance (at BMW)
Circulated devices (possible provider):
Reference CPC (D50: 10nm) (TSI?)
Engine Exhaust (EE) CPC (D50: 23nm) (BMW?)
PSL vaporizer + traceable PSL particles to check DMA (PTB?)
Flow meter (BMW?)
Laptop + data collection software “XERO” (Amium?)
Temperature/pressure/humidity sensor (connected to laptop) (Amium?)
Circulated
reference
Circulated
device under test
Terres: CPC Calibration Round Robin | Proposal of second stage |