Quick and reliable detection of toxins in the water supply
The ToxProtect is an automated monitoring system to protect a drinking water supply from accidental or malicious contamination due to harmful substances. The characteristic of these threats is a relatively high concentration of dangerous substances that occurs suddenly. Such situations must be detected quickly and safely. False alarms are reduced to an absolute minimum using the ToxProtect. This improves the trust of the operators and reduces unnecessary expenditure.
The Measurement Principle
The ToxProtect monitors the swimming activity of fish in an aquarium fed with drinking or mains water. The location of up to 10 fish and their activity is monitored continuously. Fish react sensitively to the presence of toxins and change their behaviour. The use of fish to detect toxins is an established method.
The test organisms react sensitively to most substances harmful to humans. Toxicity data are available for almost every combination of fish and toxin. To use the ToxProtect to monitor chlorinated drinking water, a dechlorination substance can be added.
The movements of the fish lead to interruptions in light barriers located in the instrument which register the entire volume of the aquarium. The activity of the fish (interrupts per minute per fish) is calculated from these interruptions. If these values fall below a pre-defined threshold, an alarm verification system is activated. In addition, immobile fish at the bottom and top of the aquarium are also registered.
The fish species can be determined by the user, the fish should be however active and have a length of 4-6 cm.
The ToxProtect detects changes in the swimming activity of the fish due to intoxication and evaluates the measurement data for alarm events. The thresholds for the alarm triggers can be set individually. High priority of the alarm emission is given to fish at the top and bottom of the aquarium, which could indicate mortality.
The ToxProtect detects for example the respiratory toxin potassium cyanide within 10 minutes at a concentration of 1 ppm.
Due to naturally occurring random variations in fish behaviour, each alarm criterion is fulfilled from time to time by accident. Hence, in order to prevent false alarms, a verification system is required. This is achieved by decreasing the illumination (turning the light off) inside the aquarium during the verification period.
Normally, this leads to a dramatic increase in fish activity. Under toxic conditions, however, this may be different. Hence, by monitoring the "increase" in activity or lack of it during modified illumination, it is possible to accept or reject the initial alarm automatically.
Operation Monitoring (Hardware Alarm)
The ToxProtect is equipped with internal sensors which refer to possible error functions. The following parameters are monitored:
- sample flow
- drain blockage
- temperature decrease
- accidental or unauthorised ambient light in the aquarium
- high chlorine concentration
Cyanide alarm within 10min at 1ppm
- sensitive to a wide range of toxins
- easy to operate
- low maintenance
- low purchasing and operating costs
- alarm reports via SMS and e-mail
In order to ensure a high level of water security, it may be necessary to operate several monitoring stations. The ToxProtect 64 is a low-priced, easy-to-operate instrument which lends itself easily to multiple application within a drinking water supply network.
- drinking water supply
- dam monitoring
- waterway analysis and assessment
- general environmental assessment
- intake monitoring
- chemical analysis
One or several ToxProtect II instruments can be monitored remotely by transferring data to the PC software (available as an option). Connections are possible via LAN, GSM modem or Internet. The software offers several possibilities for the display and anaylsis of all measurement values.
It is also possible to define different parameter settings and check the curent status of the instrument remotely.
Technical specification of our ToxProtect II
|Sensors||array of 78 light barriers|
|Measurands||activity (total, separated in rows); interruptions of light barriers due to fish movement|
|Dimensions (H x W x D)||1125 mm x 858 mm x 600mm|
|Mains supply||115/230V 50/60 Hz|
|Power consumption||200 W|
|Temperature||Sample: 5 - 28°C (dep. on fish) / Environment: 5 - 30° C|
|Transmission||up to max. 40 FTU|
|Sample flow||50 - 150 l/h|
|Aquarium volume||9 l|
|Housing protection class||IP54|
|Relay outputs||2 x 24V 1 A contacts|
|Interface||modem LAN analogue output 4-20 mA (2 X) relay output (2 X) RS232|
|Maintenance interval||> 7 days|
|Recommended fish species||fat-head minnow, tiger barb, minnow, bitterling - depending on temperature; tests for other local fish on request|
|Feeding||automatic feeder at selectable intervals|
|Number of fish||10|
|Length of fish||4-6 cm|
|Recommended period of use of fish||6 month|
Subject to alteration!