Chuanya Cao et al.YEE HSIUNG2021-07-282021-07-2820211689002https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105052130&doi=10.1016%2fj.nima.2021.165347&partnerID=40&md5=936d29caee83091876fb568609f5c24fhttps://scholars.lib.ntu.edu.tw/handle/123456789/57522726,000 3-inch photomultiplier tubes (PMTs) have been produced for Jiangmen Underground Neutrino Observatory (JUNO) by the Hainan Zhanchuang Photonics Technology Co., Ltd (HZC) company in China and passed all acceptance tests with only 15 tubes rejected. The mass production began in 2018 and elapsed for about 2 years at a rate of ?1,000 PMTs per month. The characterization of the PMTs was performed in the factory concurrently with production as a joint effort between HZC and JUNO. Fifteen performance parameters were tracked at different sampling rates, and novel working strategies were implemented to improve quality assurance. This constitutes the largest sample of 3-inch PMTs ever produced and studied in detail to date. ? 2021 Elsevier B.V.Acceptance tests; Quality assurance; Mass production; Performance parameters; Photonics technology; Sampling rates; Photomultipliers[SDGs]SDG9journal article10.1016/j.nima.2021.1653472-s2.0-85105052130