@article {Ejsmont:2017:0736-2935:584, title = "Degradation of reference tyres used for CPX measurements", journal = "INTER-NOISE and NOISE-CON Congress and Conference Proceedings", parent_itemid = "infobike://ince/incecp", publishercode ="ince", year = "2017", volume = "255", number = "7", publication date ="2017-12-07T00:00:00", pages = "584-590", itemtype = "ARTICLE", issn = "0736-2935", url = "https://ince.publisher.ingentaconnect.com/content/ince/incecp/2017/00000255/00000007/art00068", author = "Ejsmont, Jerzy and Swieczko-Zurek, Beata and Owczarzak, Wojciech and Sommer, Slawomir", abstract = "Measurements of tyre/road noise by Close Proximity Method are based on reference tyres that are described in ISO/TS 11819 3. The standard specifies two tyres, namely "P1" and "H1" that should be used during measurements. To be used for measurements each tyre must fulfill certain conditions that are listed in the standard. The conditions are related to the tread pattern depth and rubber hardness. During experiments performed at the Technical University of Gdansk (TUG) two identical tyres of "P1" stored in very different conditions type were periodically tested for hardness, tyre/road noise and rolling resistance. The paper describes results of the experiments as well as statistical data obtained by TUG during long lasting use of different "P1" tyres.", }