Voigtländer · Drinking-water hygiene in buildings
Hydreatio supports Legionella remediation in a building's drinking water with on-site generated anolyte (hypochlorous acid, HOCl), without a chlorine dioxide store. It is for technical management, facility management and hygiene officers in hospitals, care homes and property portfolios with installations subject to mandatory testing. Under the TrinkwV (German Drinking Water Ordinance), defined operator duties begin once the technical action level of 100 CFU/100 ml is reached; the technology replaces neither operational responsibility nor cause analysis.
Conformity and approvals of the Voigtländer anolyte technology, verified with independent institutes. The scope depends on the specific application.
Audience
Buyers: technical management, facility management and hygiene officers in hospitals, care homes and property portfolios with installations subject to mandatory testing.
Typical triggers for an assessment:
Not a good fit if you expect a dosing unit as the sole solution or a blanket confirmation of TrinkwV (German Drinking Water Ordinance) compliance. We sell neither. The technology supports monitored hygiene operation: it replaces neither operational responsibility nor cause analysis.
The process
From on-site anolyte production to controlled dosing and final measurement.
Modelled from the Voigtländer plant schematic of an anolyte system in a building, in the drawing language of the home page. The cards show documented facts only, no invented figures.
Duties after a finding
100CFU/100 ml technical action level (TrinkwV)
Once the technical action level of 100 CFU per 100 ml is reached, defined duties begin for the operator: notifying the public health authority, a Risikoabschätzung (risk assessment), cause analysis and measures whose effectiveness is subsequently verified. Only from that picture does it follow which technology makes sense at all.
Reliably identify the affected system, the sampling points and the measurement history.
Evaluate use, temperatures, hydraulics and possible exposure under TrinkwV; the familiar term „Gefährdungsanalyse“ (hazard analysis) means the same task.
Dead legs, stagnation, temperature problems and structural defects take priority over any dosing.
Combine remediation, operational correction and, where appropriate, monitored disinfection with documented verification of effectiveness.
Recurrence cycle
Thermal disinfection and flushing work selectively. If biofilm, stagnation zones or unfavourable temperature control remain, findings return, often in different risers.
If biofilm stays in the system, it gives Legionella lasting shelter and a growth medium: thermal flushing reaches it only in places.
Dead legs and rarely used risers hold water back; this is where findings preferentially return, and in changing parts of the system.
Where target temperatures are not held consistently, growth windows open up that a single unremarkable reading does not capture.
A single unremarkable reading does not describe the condition of a widely branched installation.
Technical approach
The legitimate objection first: continuous disinfection on its own remedies neither dead legs nor incorrect temperatures or other technical causes. Voigtländer is therefore used as one component of a monitored hygiene concept. The starting points are the finding, the causes and the way the system is operated. Dosing, measurement, documentation and, where applicable, further technical measures follow only from that.
From the finding, the causes and the mode of operation follows a monitored hygiene concept; from that follow dosing, measurement, documentation and, where needed, further technical measures. The order is deliberate: understand the installation first, then integrate the technology.
The technical approach combines four tasks:
Anolyte (hypochlorous acid, HOCl) is produced from water, salt and electricity instead of storing chlorine dioxide precursors.
The active agent is dosed into the installation as required, following measured values, not a fixed schedule.
Measurement and control make the treatment status traceable during ongoing operation.
Logged measurement and operating data support operator duties and evidence of effectiveness.
Operation
Measurement, control and logging make the treatment status traceable during ongoing operation: you can see which values are being held and where action is needed. The documentation supports operator duties and evidence of effectiveness: it replaces neither sampling by accredited laboratories nor assessment by qualified specialists.
Anolyte (hypochlorous acid, HOCl, generated on site) is produced from water, salt and electricity and dosed into the installation as required. Chlorine dioxide precursors and hazardous-substance stores are not needed with this method; the specific hazard assessment remains plant-specific. Dosing follows measured values, not a fixed schedule.
Reference
The healthcare/HVAC primary document describes ten care homes in which thermal disinfection and flushing repeatedly proved insufficient. After a test phase, Voigtländer systems secured the drinking-water values in every building.
The names have not been released; communication remains anonymised until a reference release is in place. Results are project-specific.
Further building reference
A Voigtländer system doses anolyte into the circulated hot water of a residential complex. The project began with a check of the water system.
Source: Hydreatio case studies. Results are project-specific.
What this approach does not promise:
Voigtländer in other sectors
Aviation
Buildings
Cooling systems
Food and beverage
Further applications
Every entry is a Voigtländer application. Results are project-specific and are not a forecast for another site.
Questions before the first call
No. Dead legs, stagnation, temperature problems and structural defects take priority over any dosing. Voigtländer is one component of a monitored hygiene concept; which measures the installation needs follows from the finding, the causes and the way the system is operated.
Anolyte, hypochlorous acid (HOCl), generated on site in the Voigtländer generator from water, salt and electricity. Chlorine dioxide precursors and a hazardous-substance store are not needed with this method; the specific hazard assessment remains plant-specific.
No change in taste is one of the documented conformity points of the Voigtländer anolyte technology, alongside DIN EN 901 and § 11 TrinkwV, DVGW W551, the TrinkwV approval by the Umweltbundesamt, WHO compliance and CE conformity. The scope depends on the specific application.
The active agent is dosed to demand, following measured values, not a fixed schedule. Measurement and control make the treatment status traceable during operation; the logged measurement and operating data support operator duties and evidence of effectiveness. They replace neither sampling by accredited laboratories nor assessment by qualified specialists.
The entry point is a hygiene screening: system data, findings, temperatures, mode of operation and the measures taken so far are assessed together. You receive a professional appraisal of which cause analysis, which measures and which monitoring suit your installation, and whether Voigtländer is a suitable fit for it. A finding is never evaluated on the basis of a form alone.
Under the Voigtländer brand, Hydreatio implements technical measures that may result from a risk assessment, without a chlorine dioxide store: anolyte (hypochlorous acid, HOCl) is generated on site from water, salt and electricity. Hydreatio does not carry out risk assessments; in practice, qualified specialists or specialist planners do. The operator remains responsible for commissioning and implementing the derived measures; structural and operational causes must be remedied in parallel.
Once the technical action level is reached in a drinking water installation subject to mandatory testing, the operator must act without delay and report the finding to the public health authority, unless the authorised laboratory has demonstrably already notified it. The TrinkwV and supplementary German Environment Agency recommendations point to a sequence: assess the finding, investigate causes, assess risk, implement measures, demonstrate effectiveness. Technology choice comes last.
Last reviewed: October 2026
Next step
The entry point is a hygiene screening: system data, findings, temperatures, mode of operation and the measures taken so far are assessed together. You receive a professional appraisal of which cause analysis, which measures and which monitoring suit your installation, and whether Voigtländer is a suitable fit for it.
Briefly describe the site, the findings and the measures taken so far. A few details are enough for a first contact.
Your enquiry is assessed by specialists. A finding is never evaluated on the basis of a form alone.
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Care homes kept failing the drinking water regulations despite thermal disinfection. After a test phase, the systems went into every home.
Voigtländer application in a Passivhaus residential complex.
Voigtländer technology produces the disinfectant directly on site.
Smart Match
In a few questions, Smart Match places your situation and shows the most sensible next testing step for your water system.
Legionella in drinking waterThe entry point is a hygiene screening.
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