---
title: "ASTM D3590"
url: "https://mat-cs.com/astm-d3590/"
description: "These test methods cover the determination of total Kjeldahl nitrogen. Section 24 on Quality Control pertains to these test methods."
---

ASTM Standard

# ASTM D3590

Standard Test Methods for Total Kjeldahl Nitrogen in Water

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## Significance and Use

4.1 These test methods are useful for measuring organic nitrogen and ammoniacal nitrogen, which are essential growth nutrients.

4.2 Nitrogen compounds are widely distributed in the environment. Sources of nitrogen include surface-applied fertilizers, cleaning products, and drinking water treatment aids. Because nitrogen is a nutrient for photosynthetic organisms, it may be important to monitor and control discharge into the environment.

## Scope

1.1 These test methods cover the determination of total Kjeldahl nitrogen. Section 24 on Quality Control pertains to these test methods. The following test methods are included:

Sections

Test Method A—Manual Digestion/Distillation

8 – 14

Test Method B—Semiautomated Colorimetric Bertholt

15 – 23

1.2 The analyst should be aware that precision and bias statements included may not necessarily apply to the water being tested.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.