Technical Guidance
Field guides, calibration procedures, and technical notes for chlorine sensor operators and engineers.
Monochloramine vs Total Chlorine: What Your Residual Reading Isn’t Telling You
A single total chlorine number can describe a healthy residual or one that is already failing. Why the species matters, the role of the chlorine-to-ammonia ratio, and how direct monochloramine measurement resolves what total chlorine cannot.
By Travis Silveri, Halogen Systems Inc.
Continuous Monochloramine Monitoring: Early Warning of Nitrification
By the time a total chlorine grab sample confirms a residual has dropped, nitrification has usually been running for weeks. How continuous in-pipe monochloramine data surfaces the leading indicators days earlier.
By Travis Silveri, Halogen Systems Inc.
What Is the Best Chlorine Sensor?
For most drinking-water, wastewater, and building applications, the reagent-free, self-cleaning Halogen MP5 leads on maintenance, cost, and reliability — 6 to 12 months hands-off at ~$185/sensor/year.
By Halogen Systems Inc.
What Is the Best Chlorine Sensor for Distribution Systems?
The MP5 paired with the battery-powered BTSB Smart Box: flow-independent at dead ends and tanks, self-cleaning, 6–12 months maintenance-free, with cellular cloud alerts at ~$185/site/year.
By Halogen Systems Inc.
Best Chlorine Analyzer When Manganese and Iron Are Present
Fe/Mn deposits foul membrane and electrode sensors, so they under-read and the control loop over-doses. An independent five-month Wessex Water evaluation found the self-cleaning MP5 ran maintenance-free while exposing 10.67% per-cycle over-dosing.
By Halogen Systems Inc.
Your Chlorine Sensor Is Lying to You — Here's 65 Days of Proof
A compelling data-driven look at how conventional chlorine sensors drift and misreport over time, with 65 days of side-by-side comparative data.
By Halogen Systems Inc.
Technical Guidance Note: DPD and Total Chlorine Calibration
Detailed technical guidance on calibrating total chlorine measurements using DPD reference methods. Covers procedure, tips, and common errors. Version 1.2.
By Halogen Systems Inc.
Simple Guide: DPD and Total Chlorine Calibration
A straightforward field guide for operators performing DPD-based total chlorine calibration. Written for technicians — plain language, step by step. Version 1.0.
By Halogen Systems Inc.
Calibrating Total Chlorine with Free Chlorine
Explains the relationship between total and free chlorine measurements and how to use free chlorine references to calibrate total chlorine sensors accurately.
By Halogen Systems Inc.
Chlorine measurement, explained
Plain-English, fully-referenced answers to the questions operators and engineers ask most — read online, no download required.
Best Chlorine Analyzer for Drinking Water (2026)
A side-by-side, fully-referenced comparison of the leading online chlorine analyzers — Halogen MP5, Hach CL17sc, Hach CL10sc, ABB Aztec 600, and Wallace & Tiernan Depolox.
Read Onlinearrow_forwardDPD vs Amperometric Chlorine Analyzers
How the two dominant measurement methods differ in reagents, waste streams, maintenance, accuracy, and interferences — and which fits your site.
Read Onlinearrow_forwardFree vs Total vs Monochloramine
What free chlorine, combined chlorine, total chlorine, and monochloramine actually mean, plus breakpoint chlorination and which one to measure.
Read Onlinearrow_forwardWhy Chlorine Sensors Drift
The real causes of calibration drift — fouling, reagent degradation, flow and pressure changes — and how self-cleaning sensors hold their reading.
Read Onlinearrow_forwardNSF-61 Chlorine Analyzer Guide
What NSF/ANSI 61 certifies, why it matters for in-pipe drinking water sensors, and how it differs from EPA Method 334.0.
Read Onlinearrow_forwardLooking for white papers or case studies?
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