GB/T 18920-2020The reuse of urban recycling water—Water quality standard for urban miscellaneous use (English PDF)

Foreword

This Standard was drafted according to the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 18920-2002 "The reuse of urban recycling water - Water quality standard for urban miscellaneous water consumption".

Compared with GB/T 18920-2002, the main technical changes, except for editorial changes, are as follows.

- DELETE GB/T 3181, GB/T 7494, GB/T 11898 in the normative references;

ADD references to GB 50084, CJ/T 158, HJ 505, HJ 506 (see Clause 2 of this Standard, Clause 2 of the 2002 edition);

- ADD the term "reclaimed water" and its definition (see 3.1 of this Standard);

- In Table 1, REVISE the basic control item "total coliforms" TO "Escherichia coli, and MODIFY some water quality indicator values such as turbidity, biochemical oxygen demand after 5 days, ammonia nitrogen, total dissolved solids, total chlorine (see Table 1 of this Standard, Table 1 of the 2002 edition);

- ADD the limits of chloride and sulfate in the selective control items (see 4.2 of this Standard);

- MODIFY the sampling and testing frequency of some water quality indicators such as turbidity and total chlorine (see Table 5 of this Standard, Table 3 of the 2002 edition);

- DELETE "Standard implementation and supervision"; SEPARATE "Safe use" into a clause (see Clause 6 of this Standard, Clause 6 of the 2002 edition).

1 Scope

This Standard specifies the terms and definitions, water quality indicators, sampling and monitoring, safe use of water for urban miscellaneous use in the reuse of urban recycling water.

This Standard applies to reclaimed water for miscellaneous use, such as toilet flushing, vehicle washing, urban landscaping, street sweeping, fire protection, construction site and concrete production.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 5750.4 Standard examination methods for drinking water - Organoleptic and physical parameters

GB/T 5750.5 Standard examination methods for drinking water - Nonmetal parameters

GB/T 5750.6 Standard examination methods for drinking water - Metal parameters

GB/T 5750.11 Standard examination methods for drinking water - Disinfectants parameters

GB/T 5750.12 Standard examination methods for drinking water - Microbiological parameters

GB/T 7488 Water quality - Determination of biochemical oxygen demand after 5 days (BOD5) - Dilution and seeding method

3 Terms and definitions

For the purpose of this document, the following terms and definitions apply.

4 Water quality indicators

4.1 The basic control items and limits for water quality of water for urban miscellaneous use shall meet the requirements of Table 1.

4.3 Water for concrete shall also comply with the relevant provisions of JGJ 63.

4.4 For water used in the automatic sprinkler fire-fighting system, in addition to meeting the requirements of Table 1, the suspended matter shall meet the requirements of GB 50084.

5 Sampling and monitoring

6 Safe use