GB/T 15231-2023 Chinese PDF (GB/T15231-2023) GB 5009.31-2025 40-2024_Chinese: Specifications for optical fibre

40-2024_Chinese: Specifications for optical fibre test methods - Part 40: Measurement methods and test procedures for transmission characteristics - Attenuation (Chinese: 光纤试验方法规范 第40部分：传输特性的测量方法和试验程序 衰减)

GB/T 45308-2025_Chinese: Railway applications - Rolling stock - Technical requirements for network time synchronization (Chinese: 轨道交通 机车车辆 网络时间同步技术要求)

GB 45672-2025_Chinese: On-board accident emergency call system (Chinese: 车载事故紧急呼叫系统)

GB/T 44962-2024_Chinese: Grain and oil machinery - Wheat debranner (Chinese: 粮油机械 小麦剥皮机)

GB 12358-2024_Chinese: Gas detection and alarm instruments for workplace - General technical requirements (Chinese: 作业场所环境气体检测报警仪器 通用技术要求)

GB/T 15231-2023 Chinese PDF (GB/T15231-2023) GB 5009.31-2025 40-2024_Chinese: Specifications for optical fibreGB T 15231 2023_Chinese: Test methods for the properties of glassfibre reinforced cement (Chinese: ) Note Careful: Text of PDF is in Chinese (not English). Delivery (PDF in Chinese): 2 working hours typically, ASAP English versions: GB T 15231 2023