On‑site Monitoring Practice of YUNTANG YT‑SXT1 Portable Turbidimeter for Complex Surface Water in Environmental Field Surveys

Turbidity is one core physical indicator reflecting water quality status. Suspended sediment, algae, organic particulate contaminants in rivers, lakes and reservoirs will change water turbidity value. For environmental monitoring agencies, laboratory off‑line testing cannot fully reflect real‑time water conditions, and field portable measuring instruments become indispensable tools for routine patrol and sudden water pollution emergency response. The YUNTANG YT‑SXT1 handheld turbidimeter follows the nephelometric scattering measurement principle specified in HJ1075‑2019, adopting 860 nm single‑wavelength LED light source. The 90‑degree scattered light detecting mode can effectively reduce measurement interferences brought by water sample chroma, improving accuracy for colored natural water bodies.

This turbidimeter runs on Android operating system, equipped with a 4.3‑inch high‑definition touch screen with intuitive graphic‑driven operation interface. The measuring range covers 0‑2000 NTU, resolution reaches 0.001 NTU, and instrument repeatability is ≤0.5%. It is built with 16 GB large‑capacity local memory, capable of storing more than 10 000 groups of on‑site test records. Rich data communication functions including Wi‑Fi, Bluetooth and USB interface support diverse data‑export scenarios: users can transfer bulk measurement data to personal computers, or match Bluetooth printer to print reports immediately at sampling sites. The whole machine reaches IP65 protection grade. The detection cell can resist accidental invasion of 0.5 mL liquid splashing, adapting to humid, dusty and complicated outdoor field environments. Powered by an 8000 mAh lithium battery with USB‑C universal charging protocol, field workers can charge it with mobile power banks or common phone chargers without special dedicated power adapters, greatly improving flexibility for outdoor long‑time sampling missions.

In our field investigation project for regional surface‑water environmental monitoring, we deployed YT‑SXT1 to complete turbidity sampling work for dozens of river and reservoir sampling points. During field operation, zero‑point calibration and multi‑point standard calibration can be finished in a short time without complicated pre‑heating procedure for the LED light source. The instrument can automatically switch internal measurement ranges according to sample turbidity levels. Multiple output units such as NTU, FAU, FNU, EBC are optional to meet different domestic and international standard reporting requirements. We selected partial water samples to take back to laboratory for comparative testing with bench‑top reference turbidimeter. Statistical comparison shows that the field test data from YT‑SXT1 possesses good consistency with laboratory reference results. In practical work, this instrument is applicable for water plant inflow‑outlet monitoring, sewage‑treatment‑plant process inspection, aquaculture water condition evaluation and environmental emergency detection. It balances portability, measuring performance and data‑management capacity for front‑line water‑quality monitoring teams.