NSF International tests
Dipl.-Ing. Anna Lefering
Tests according to NSF/ANSI standards are recommended if you would like to enter the American and Asian markets with relative ease.
Currently, the only place in Europe where tests according to NSF/ANSI Standards 40, 245 and 350 can be carried out is on PIA's test field in Aachen. For over ten years, PIA has maintained successful cooperation with NSF.
Parameter | NSF 40 | NSF 245 | NSF 350 |
---|---|---|---|
BOD | • | • | • |
TSS | • | • | • |
Nitrogen | • | • | |
Turbidity | • | ||
E. coli | • |
NSF/ANSI 40: Residential Wastewater Treatment Systems
The standard NSF/ANSI 40 (“Residential On-site Systems”) describes a testing and certification procedure for domestic wastewater treatment plants (small wastewater treatment plants) with a daily treatment capacity from 1,514 to 5,678 l/day (equivalent to 400 to 1,500 gallons/U.S. liq. gal.).
The suitability of the system under test is not tied to specific treatment technologies.
parameter | 30 d average | 7 d average |
---|---|---|
CBOD5 | <25 mg/l | <40 mg/l |
TSS | <30 mg/l | <45 mg/l |
pH | between 6.0 and 9.0 | |
Odor | non offensive | |
Oily film and foam | non-detectable |
parameter | requirements | |
---|---|---|
CBOD5 | no more than 10% of CBOD5-data in effluent shall exceed 60 mg/l | |
TSS | no more than 10% of TSS-data in effluent shall exceed 100 mg/l | |
pH | between 6.0 and 9.0 |
NSF/ANSI 245: Nitrogen Reduction
The standard NSF/ANSI 245 describes minimum requirements for plants that include nitrogen removal and represents a modular extension of the process according to NSF/ANSI 40.
When the plant achieves Class I (effluent quality, limit values to be complied with see above) within the NSF/ANSI 40 testing, it is then possible to conduct the test according to NSF/ANSI 245 (to be demonstrated either by prior, separate NSF/ANSI 40 testing or by simultaneous NSF/ANSI 40 and NSF/ANSI 245 testing). For this, the mean total nitrogen content in the effluent must be reduced by at least 50% compared to the influent.
NSF/ANSI 350: Onsite Residential and Commercial Water Reuse Treatment Systems
The method NSF/ANSI 350 test methods apply to greywater treatment systems as well as to domestic wastewater treatment plants (small wastewater treatment plants). Compared to the standard NSF/ANSI 40 and 245 NSF/ANSI 350 has additional requirements applying to the turbidity and the E. coli concentration of the effluent.
Further informations regarding the NSF/ANSI 350 tests can be found » here.