GB/T 19520.21-2023 Chinese PDF (GB/T19520.21-2023) GB/T 26846-2024 English versions: GB/T 45169-2025

English versions: GB/T 45169-2025

English versions: GB/T 33588

1-2025_Chinese: Testing and calculating methods for seasonal performance factor of energy recovery ventilators for outdoor air handling - Part 1: Seasonal performance factor of sensible heating recovery (Chinese: 热回收新风机组季节性能系数测试和计算方法 第1部分：供热显热回收季节性能系数)

English versions: GB/T 45099-2024

GB 14167-2024_Chinese: Safety-belt anchorages and restraint systems anchorages for occupants of power-driven vehicles (Chinese: 机动车乘员用安全带和约束系统安装固定点)

GB/T 19520.21-2023 Chinese PDF (GB/T19520.21-2023) GB/T 26846-2024 English versions: GB/T 45169-2025GB T 19520. 21 2023_Chinese: Mechanical structures for electrical and electronic equipment Dimensions of mechanical structures of the 482. 6 mm (19 in) series Part 3 109: Dimensions of chassis for embedded computing devices (Chinese: 482. 6 mm(19 in) 3 109) Note Careful: Text of PDF is in Chinese (not English). Delivery (PDF in Chinese): 2 working hours typically, ASAP English versions: GB T 19520. 21 2023