探测管 meaning in English

exploring tube
sound-pipe
sounding pipe

Detector tube type carbon monoxide measuring instruments colour - intensity
探测管式一氧化碳测量仪色比度
Detector tube type carbon monoxide measuring instruments length - of - stain
探测管式一氧化碳测量仪染色长度
Ship service tank piping systems ; filing and pressure equalizing equipment ; sounding pipes
船舶维护油箱管道系统.灌装与压力平衡设备.探测管
Superstructure compressed air ( water supply 、 fire fighting 、 smoke detection ) piping to be done air - tightness test
上层建筑压缩空气管系（供水管、消防管、烟雾探测管）密性试验。
Workplace atmospheres - short term detector tube measurement systems - requirements and test methods ; german version en 1231 : 1996
工作场地空气环境.短时探测管测量系统.要求和试验方