understanding our quality products

When a shipping industry representative said to the Halogen Systems President Michael Silveri that his lofty goals were an impossibility, Silveri only grew more determined. “He told me, ‘Big companies haven’t been able to do it.  We don’t really think you can do it,’” Silveri said. “Incidentally, they’re now a customer.”

DNV Type Approval

DNV GL is a globally leading quality assurance and risk management company. With 100,000 customers across the maritime, oil and gas, energy, as well as a range of other sectors, DNV GL helps companies to become safer, smarter and greener.

Supporting Innovation To Better Understand Global Waters

ACT is a partnership of research institutions, resource managers, and private sector companies dedicated to fostering the development and adoption of effective and reliable sensors and platforms for use in coastal, freshwater and ocean environments

Promoting Safe Ships and Clean Oceans

Boosting technologies related to ships, land & offshore facilities that enhance safety of life, property, and protecting the environment

Small Business Innovation Research Success Story

Through their small business solicitation they found a better solution for a critical issue: biofoul control.

Evironmental testing

In compliance with:

  • LR Rule
  • DNV 2.4
  • Tests included
  • Vibration
  • Susceptibility
  • EMI
  • Temp & Humidity Cycling


How long will sensor last
The chlorine sensor should last the life of the system. No maintenance is usually necessary. It the event of abuse, it can be reconditioned by polishing.

How often does the sensor measure?
The sensor measures all five parameters Chlorine, pH, ORP, Salinity and Temperature every 50 seconds.

What are the scheduled maintenance requirements?
We recommend a calibration check be performed every 60 days and a pH calibration check every year. Wear parts and the pH sensors are replaced every two years.

Will the sensor work in fresh water?
Yes. It will measure accurately from 200 µS up to fully marine seawater 45 mS (34 PSU). It will likewise measure accurately in waters with a pH of 6.5 to 9.

Why does the sensor measure pH?
While pH of seawater does not change much, in brackish or freshwater, the pH can change drastically from 6.5 to 9.0.

How is HSI’s Fast Response ORP Different from typical discrete ORP?
Usually. HSI’s ORP measurement technique is different than a convention dedicated ORP unit. It could vary by as much as 50 mV but should provide qualitative readings comparable to a dedicated unit. It is not subject to poisoning and will respond faster to changes in some cases.

How is Halogens pH sensor unique?
Halogen uses a unique pH cartridge in its sensor system. The pH cartridge can withstand 10 bar to -0.7 bar pressures and rapidly wets if allowed to dry out. Accuracy is restored within 3 minutes. The pH electrode is only one available with these specifications. It does not require calibration for a year or more. Cartridges are replaced every two years.

Is the Sensor Type Approved?
Yes. Both the ATEX/IECEx and the Non-Hazardous versions are Type Approved by the Korean Registry of Shipping (KR).

comparison #1

DPD Online Instruments VS. the Halogen Sensor

In Ballast Water Treatment Systems (BWTS) for larger ships, generated residual oxidant systems, resulting from either ozone or electrolytic generation, inactivates invasive species. In both cases, the residual oxidant is bromine.

Sensors and/or analyzers are used both to control the level of oxidant generated during ballasting and to detect the residual oxidant levels before deballasting (ballast water pumped out) operations occur. During ballasting, water is loaded, treated and monitored to ensure inactivation of invasive species is complete.  During deballasting, sensors monitor the residual oxidant level to ensure that the residual concentration is below 0.2 (0.1 in some cases) ppm. This is a regulatory level required by International Maritime Organization and the US Coast Guard.

Most BWTS systems use N,N-diethyl-p-phenylenediamine, (DPD) Instrumentation at various locations on board the ship. These units use regent feed colorimeters to indicate Total Oxidant levels. They require a relatively long cycle time of 75 seconds before displaying a reading.  In addition to the cycle time, discarding the first or second measurement is typical due to initial inaccuracies. This delay is further compounded when the sample water must flow hundreds of feet to the colorimeter location before analysis can occur on larger ships. Sampling pumps, water lines and automated valves must be added to system which complicate and CAPEX costs.

While no analytical method is perfect, DPD Instruments suffer from a number of limitations in this application. They require:

  • Use of tubing as small 1mm (ID) which has a tendency to clog (Via dried reagents or biofouling)
  • Filtration of the sample (Increase turbidity causes inaccuracies)
  • Filter cleaning
  • Cleaning of the colorimeter with acid every 60 days
  • Regent replacement every 60 days
  • Disposal of a waste stream

In general, these systems are complicated, difficult to troubleshoot and require considerable maintenance. This is problematic on a ship since there is typically a small crew with many duties during ballasting and deballasting (when these systems are used).

Halogen Systems, Inc. manufactures Water Treatment sensors for Seawater, drinking water, swimming pools and cooling towers. It’s Oxidant/ Deoxidant Sensor for use in Ballast Water Treatment Systems is currently on-board ships.  The sensor is installed directly in the ballast pipe and measures TRO every 50 seconds. These measurements are accurate within two, and sometimes one, cycle.

Halogen Systems’ Oxidant Sensor has some advantages in this application:

  • Long interval between calibrations
  • Self- cleaning electrodes
  • Flow independent measurement
  • Direct pipe insertion
  • Integrated salinity measurement
  • Auto ranging oxidant measurement from 0.07 ppm to 15 ppm
  • No electrolytes or membranes
  • Biofouling resistant

Halogen Systems sensor was designed with this challenging application in mind. It has a solution that can potentially save on both OPEX and CAPEX costs while simplifying operation by ship’s crew.