KS I ISO 24511-2019 Activities relating to drinking water and wastewater services ― Guidelines for the management of wastewater utilities and for the assessment of wastewater services
2019KS I ISO 24511:2019 Activities relating to drinking water and wastewater services ― Guidelines for the management of wastewater utilities and for the assessment of wastewater services
2013KS I ISO 24511:2013 Activities relating to drinking water and wastewater services ― Guidelines for the management of wastewater utilities and for the assessment of wastewater services