| GTR No. 23 L-vehicle Pollution Control Durability | Durability of L-category Vehicle Pollution Control Devices | Requirements for Two- and Three-wheeled Light Motor Vehicles with regard to the Durability of the Pollution Control Devices This proposed global technical regulation would supplement the three main environmental performance verification test types (i.e., I, II, and VII as envisioned for GTR No. 2 by the Informal Working Group on Environmental and Propulsion Performance Requirements of L-category vehicles (EPPR)) with procedures for verifying pollution device/system durability. This effort includes both the development of the GTR and its UN Regulation counterpart. For convenience, materials concerning both efforts are grouped here. L-vehicle Pollution Control Durability Durability of L-category Vehicle Pollution Control Devices GTR No. 23 GTR No. 23 | GTR | 23 |