ISO 31800:2020

a) primarily treat faecal sludge,

b) are able to operate in non-sewered and off-grid environments,

c) are prefabricated,

d) exhibit resource recovery capability (e.g. recovering energy, reusable water, soil amendment products), and are capable of being energy neutral or energy net positive.

This document does not apply to treatment units requiring major sewer infrastructure.

Inputs are primarily faecal sludge derived from human excreta and can include additional substances at the discretion of the manufacturer. This document does not specify the characteristics of the faecal sludge (e.g. COD, BOD, moisture content, etc.) and which forms of the additional inputs (e.g. food waste) are treated within the unit. These inputs are defined by the manufacturer as well as the input characteristics which meet the requirements specified in this document.

This document addresses:

— the performance, safety, operability, and maintainability of the treatment unit,

— the protection of human health and the environment,

— safety aspects of the treatment unit's solid, liquid, and gaseous outputs,

— noise and odour outputs of the treatment unit.

This document specifies minimum requirements of all types of outputs from the treatment unit. It does not specify or mandate the quality of resources recovered as these are highly dependent on the local (e.g. economic, social) context.

Any resources produced and consumed internally to the process itself are outside the scope of this document. Similarly, with the exception of pathogen requirements, the quality and value of any resource recovery and reuse products derived from the treatment unit are outside the scope of this document. Apart from the requirement for energy independence under manufacturer specified input conditions during steady-state operation, this document does not set performance targets with respect to the amount or type of energy or resources to recover and/or use locally.

This document does not address transportation and any intermediary processes required to supply the treatment unit with the defined inputs. Provisions of this document apply to the treatment unit according to its unit boundaries, i.e. within the process chain beginning with its specified inputs and ending with its outputs. Some of the considerations on sustainability of the treatment unit are highlighted in Annex B.