Certification mark for Faecal Sludge Treatment Units

Certification mark for Faecal Sludge Treatment Units

Adding value with our service portfolio

Adding value with our service portfolio

Certification mark for Faecal Sludge Treatment Units (FSTU)


The full ISO 31800 certification applies to faecal sludge treatment units (FSTU) which: 

(a) primarily treat faecal sludge,

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

(c) are prefabricated, and

(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.



The certification mark is based on the ISO 31800: 2020 standard. This standard defines the performance, safety, and sustainability of community-scale resource recovery faecal sludge treatment units as well as technical robustness and safety in terms of human health and the environment.



  • Faecal sludge treatment units

    A faecal sludge treatment unit is a system which primarily treats faecal sludge that is collected from on-site sanitation technologies, like septic tanks or pit latrines, to an acceptable standard for safe reuse or disposal. Additional materials may be included in the system input, subject to the decision of the unit’s manufacturer.

  • Energy independent
    An energy independent treatment unit is able to perform its intended functions relying exclusively on energy from faecal sludge as defined by the manufacturer during steady state operation.
  • Pre-fabricated
    A pre-fabricated unit is one that is factory produced, either as a fully assembled unit or as a set of components that assemble to form the unit.
  • Community-scale
    Community-scale resource recovery faecal sludge treatment units serve approximately, but not limited to, 1000 to 100 000 people.
  • Resource recovery
    The resource recovery of a treatment unit refers to its use of input to generate valuable outputs.
  • Type tested
    The voluntary certification mark with the statement “Type tested” is issued for products, indicating that a product of this type was tested and certified by the independent third-party organisation of TÜV SÜD Product Service for conformity with the essential technical safety requirements.
  • Production monitored

    Periodic surveillance of the manufacturer of a product constitutes the basic premise for certification which includes the award of a certification mark. Certification always requires product testing and regular factory inspections.

    As a third-party expert organisation, TÜV SÜD verifies that the manufacturer is able to maintain consistent quality in line with the requirements throughout high-volume production and has established the necessary quality system, including incoming goods inspections, lists of materials and final product check.

    In addition, calibration of the necessary measuring and monitoring equipment must be ensured. Surveillance and/or monitoring covers the testing of safety-critical components and other materials used. If unauthorised changes are made to the product, the certificate will be withdrawn and the TÜV SÜD certification mark may no longer be used.

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