General information:
Organic substances in water do not have a harmful effect on the human body and do not limit the use of water. Their sanitary importance lies in the fact that they are indicators of water pollution with other elements, especially microorganisms, which represent an epidemiological risk for the population.
Organic substances can be natural (specific to the soil from which they are trained in water layers) or artificial, coming from pollution. They can also be of plant or animal nature, the latter being generally spontaneous to a higher density of microorganisms.
In assessing the pollution of water a special significance is presented by the sudden increases of the values of organic matter, which raises the intervention of a pollution.
The organic substances in the water are determined by the oxidation of organic matter with oxidizers KMnO4 or K2CrO7. The method is also known as the index of permanganate.
Referential after which the analysis is performed:
The analysis for determining the hardness of drinking water is performed within its own laboratory according to the standard national SR EN ISO 8467:2001.
Principle of the method:
Determination of hardness in drinking water is performed by titration with potassium permanganate.
Sample rejection cases – quantity of inappropriate sample, sample collected in inappropriate containers, samples not properly labelled, etc.
Recipient – clean container.
The amount of sample required to perform the analysis - minimum 210ml.
Sample stability – freshly harvested water is stable for 2 days at 2-8°C or 6 hours at ambient temperature.
The analysis method - volumetrica.
Reference values according to the Water Law1)
Parameter / Unit of measurement | CA value (Maximum permissible concentration) |
|
max. 5 |
Recommendations for performing the analysis/ Effects of exceeding the reference values –
A high oxidation value indicates a water pollution, so a special significance is shown by the sudden increases in the values of organic matter, which raises the intervention of a pollution.
To reduce water hardness, filters and special installations are often used.
Bibliography:
- LEGEA 458/2002 as amended and supplemented by Law no. 311/2004, Government Ordinance no. 11/2010, Law no. 124/2010 and Government Ordinance no. 1/2011