LaMotte 2020wi Portable Turbidity Meters - Manual (Page 16)

Acronyms Defi nitions Notes
Regulatory
Method
NTU Nephelometric
Turbidity Units
Incandescent white
light between 400 and
600 nm, 90° detection,
2020we
EPA 180.1
FNU Formazin
Nephelometric
Units
IR LED (usually) 860
nm, bandwidth less than
60 nm, 90° detection,
2020wi
ISO 7027
AU Attenuation
Units
Incandescent white
light between 400 and
600 nm, 180° detection,
2020we
Not
applicable
FAU Formazin
Attenuation
Units
IR LED (usually) 860
nm, bandwidth less than
60 nm, 180° detection,
2020wi
ISO 7027
ASBC American
Society of
Brewing
Chemists
2020we/wi Not
applicable
EBC European
Brewery
Convention
2020we/wi Not
applicable
The 2020we and 2020wi each use two turbidity units. The 2020we
reports the result as NTU when the 90° detector is used and AU when
the 180° detector is used. The 2020wi reports the result as FNU when
the 90° detector is used and FAU when the 180° detector is used.
 TAKING TURBIDITY WATER SAMPLES
Clean plastic or glass containers may be used for turbidity samples.
Ideally, samples should be tested soon after collection and at the same
temperature as when collected.
16
Options/Set Up