Johkasou Terminology
Building Standards Law
A law that stipulates standards for sites, structure, equipment and usage of buildings
Certified structure type johkasou
A johkasou that is designed with the same or higher treatment performance as those listed in the Structural Standard for Johkasou, but with a different structure.
Domestic wastewater treatment plan
Consisting of a long-tern plan and an annual plan made by municipalities for treatment of domestic wastewater in their respective administrative districts. It is the responsibility of municipalities to treat and manage municipal waste including solid waste and domestic wastewater under the Waste Disposal and Public Cleansing Law.
Gappei-shori johkasou
A johkasou that is designed for treating domestic wastewater, usually used to distinguish this device from Tandoku-shori Johkasou. "Gappei" means combined and "shori" means treatment in Japanese, while “johka” means purification, “sou” means tanks.
JIS A3302 （JIS A3302 ）
One of the Japan Industrial Standards (JIS), it describes how to decide the population suitable for the capacity of a johkasou to be installed/constructed for buildings of different uses.
Johkasou
A kind of device used for domestic wastewater treatment; which is constructed or installed by the Johkasou Law on site for houses, buildings or communities.
Johkasou desludging technician
A kind of qualification used to designate one type of occupation integral to the johkasou desludging business; vendors are required to be engaged in desludging of johkasou.
Johkasou Law
A law that stipulates regulations for johkasou manufacturing, installation, operation/maintenance, desludging, inspection of johkasou, and administering examinations and training for the attainment of qualifications for johkasou businesses.
Johkasou inspector
A kind of qualification used to designate one type of occupation integral to the johkasou business. This is required when one is to be engaged in conducting legal inspections of johkasou. An inspector should belong to a Specified Inspecting Agency.
Johkasou installation worker
A kind of qualification used to designate one type of occupation integral to the johkasou business. This designation is required for one to be engaged in installation or construction of johkasou. A johkasou installation worker should have a wealth of knowledge about johkasou systems, especially regarding their installation.
Johkasou operator
A kind of qualification used to designate one type of occupation integral to the johkasou business. This title is required when one is to be engaged in operation and maintenance of johkasou. A johkasou operator should have a wealth of knowledge about johkasou, especially regarding their operation and maintenance.
Johkasou system
One kind of domestic wastewater treatment systems in Japan, for on-site or small-scale centralized treatment, which are defined and regulated by the Johkasou Law.
Johkasou technical supervisor
A kind of qualification used to designate one type of occupation integral to the johkasou business. This title is required for management of johkasou with NUD exceeding 500.
Johkasou with advanced treatment processes
Johkasou capable of removing nitrogen and/or phosphorus, or johkasou with membrane modules .
Large-scale johkasou
A johkasou having a NUD exceeding 500, usually made of reinforced concrete on installation site for treatment of domestic wastewater from a village or several buildings.
A law that stipulates standards for sites, structure, equipment and usage of buildings
Certified structure type johkasou
A johkasou that is designed with the same or higher treatment performance as those listed in the Structural Standard for Johkasou, but with a different structure.
Domestic wastewater treatment plan
Consisting of a long-tern plan and an annual plan made by municipalities for treatment of domestic wastewater in their respective administrative districts. It is the responsibility of municipalities to treat and manage municipal waste including solid waste and domestic wastewater under the Waste Disposal and Public Cleansing Law.
Gappei-shori johkasou
A johkasou that is designed for treating domestic wastewater, usually used to distinguish this device from Tandoku-shori Johkasou. "Gappei" means combined and "shori" means treatment in Japanese, while “johka” means purification, “sou” means tanks.
JIS A3302 （JIS A3302 ）
One of the Japan Industrial Standards (JIS), it describes how to decide the population suitable for the capacity of a johkasou to be installed/constructed for buildings of different uses.
Johkasou
A kind of device used for domestic wastewater treatment; which is constructed or installed by the Johkasou Law on site for houses, buildings or communities.
Johkasou desludging technician
A kind of qualification used to designate one type of occupation integral to the johkasou desludging business; vendors are required to be engaged in desludging of johkasou.
Johkasou Law
A law that stipulates regulations for johkasou manufacturing, installation, operation/maintenance, desludging, inspection of johkasou, and administering examinations and training for the attainment of qualifications for johkasou businesses.
Johkasou inspector
A kind of qualification used to designate one type of occupation integral to the johkasou business. This is required when one is to be engaged in conducting legal inspections of johkasou. An inspector should belong to a Specified Inspecting Agency.
Johkasou installation worker
A kind of qualification used to designate one type of occupation integral to the johkasou business. This designation is required for one to be engaged in installation or construction of johkasou. A johkasou installation worker should have a wealth of knowledge about johkasou systems, especially regarding their installation.
Johkasou operator
A kind of qualification used to designate one type of occupation integral to the johkasou business. This title is required when one is to be engaged in operation and maintenance of johkasou. A johkasou operator should have a wealth of knowledge about johkasou, especially regarding their operation and maintenance.
Johkasou system
One kind of domestic wastewater treatment systems in Japan, for on-site or small-scale centralized treatment, which are defined and regulated by the Johkasou Law.
Johkasou technical supervisor
A kind of qualification used to designate one type of occupation integral to the johkasou business. This title is required for management of johkasou with NUD exceeding 500.
Johkasou with advanced treatment processes
Johkasou capable of removing nitrogen and/or phosphorus, or johkasou with membrane modules .
Large-scale johkasou
A johkasou having a NUD exceeding 500, usually made of reinforced concrete on installation site for treatment of domestic wastewater from a village or several buildings.
Legal inspection
There are two kinds of legal inspections for johkasou: a) inspection after its installation or construction; b) annual inspection, in accordance with the Johkasou Law. The legal inspection includes a visual inspection, a water quality inspection and a document inspection.
Medium-scale johkasou
A johkasou having a NUD between 51 to 500, usually made of plastics, for treatment of domestic wastewater from mini communities.
Night soil treatment and organic waste recycling center
A new type of night soil treatment facility, treating and recycling collected night soil, and johkasou sludge and other organic waste using recycling technologies as well as traditional wastewater treatment technologies.
ight soil treatment facility
A plant for treating collected night soil and johkasou sludge, in some cases biomass reactors is incorporated as part of the facility.
Number of users for design (NUD or p.e.)
A value calculated by JIS A3302, to determine the population equivalent for the capacity of a johkasou to be installed/ constructed. A NUD is equal to the unit of pollutant load for johkasou, which is defined to be 200 L/cap.day for wastewater, 40 g/cap.day for BOD loads, 10 g/cap.day for nitrogen loads and 1 g/cap.day for phosphorus loads.
Rural sewerage system
One of the domestic wastewater treatment systems in Japan, for small centralized treatment in rural areas; it is also classified as johkasou under the Johkasou Law.
Small-scale johkasou
A johkasou having a NUD of less than 51, usually made ofplastics, for treatment of domestic wastewater from individual households or mini communities.
Specified inspection agency
Designated by the prefectural governor as a public institution to administer the legal inspection for johkasou professionals.
Standard structure johkasou
A johkasou that is designed in line with the Structural Standards for Johkasou, so that the structure and the required volume of each tank comply with these standards.
Structural standard for johkasou
A standard that outlines the structure and performance of johkasou. There are twelve categories and sixteen treatment processes listed.
Tandoku-shori johkasou
A johkasou that is designed for treating wastewater from exclusively from flush toilets, usually used for the purpose of distinguishing these johkasou from Gappei-shori johkasou. “Tandoku" means sole or exclusive in Japanese. Manufacture and installation of Tandoku-shori johkasou are prohibited in principle by the Johkasou Law as of April 1, 2001.
Treatment process
Treatment processes of johkasou that are defined in Structural Standard for Johkasou for standard structure type johkasou, or approved by the Minister of Land, Infrastructure and Transport for certified structure type johkasou.
Unit equipment
A tank or a device in a johkasou that has a special, independent function; usually described in the flowchart of johkasou.
Vault toilet
A kind of traditional Japanese toilet; under which a night soil storage tank is prepared and the night soil is withdrawn and transported for treatment.
Waste Disposal and Public Cleansing Law
A law that stipulates regulations of management and disposal of all kinds of discharged wastes (excluding radioactive wastes and wastes polluted by radioactivity). It regulates the collection, transport and disposal of johkasou sludge withdrawn in the desludging of johkasou.
Water Pollution Control Law
A law that stipulates regulations on the discharge of wastewater from factories, buildings, etc. to public bodies of water using effluent standards; designed to promote domestic wastewater treatment to protect public bodies of water from water pollution.
There are two kinds of legal inspections for johkasou: a) inspection after its installation or construction; b) annual inspection, in accordance with the Johkasou Law. The legal inspection includes a visual inspection, a water quality inspection and a document inspection.
Medium-scale johkasou
A johkasou having a NUD between 51 to 500, usually made of plastics, for treatment of domestic wastewater from mini communities.
Night soil treatment and organic waste recycling center
A new type of night soil treatment facility, treating and recycling collected night soil, and johkasou sludge and other organic waste using recycling technologies as well as traditional wastewater treatment technologies.
ight soil treatment facility
A plant for treating collected night soil and johkasou sludge, in some cases biomass reactors is incorporated as part of the facility.
Number of users for design (NUD or p.e.)
A value calculated by JIS A3302, to determine the population equivalent for the capacity of a johkasou to be installed/ constructed. A NUD is equal to the unit of pollutant load for johkasou, which is defined to be 200 L/cap.day for wastewater, 40 g/cap.day for BOD loads, 10 g/cap.day for nitrogen loads and 1 g/cap.day for phosphorus loads.
Rural sewerage system
One of the domestic wastewater treatment systems in Japan, for small centralized treatment in rural areas; it is also classified as johkasou under the Johkasou Law.
Small-scale johkasou
A johkasou having a NUD of less than 51, usually made ofplastics, for treatment of domestic wastewater from individual households or mini communities.
Specified inspection agency
Designated by the prefectural governor as a public institution to administer the legal inspection for johkasou professionals.
Standard structure johkasou
A johkasou that is designed in line with the Structural Standards for Johkasou, so that the structure and the required volume of each tank comply with these standards.
Structural standard for johkasou
A standard that outlines the structure and performance of johkasou. There are twelve categories and sixteen treatment processes listed.
Tandoku-shori johkasou
A johkasou that is designed for treating wastewater from exclusively from flush toilets, usually used for the purpose of distinguishing these johkasou from Gappei-shori johkasou. “Tandoku" means sole or exclusive in Japanese. Manufacture and installation of Tandoku-shori johkasou are prohibited in principle by the Johkasou Law as of April 1, 2001.
Treatment process
Treatment processes of johkasou that are defined in Structural Standard for Johkasou for standard structure type johkasou, or approved by the Minister of Land, Infrastructure and Transport for certified structure type johkasou.
Unit equipment
A tank or a device in a johkasou that has a special, independent function; usually described in the flowchart of johkasou.
Vault toilet
A kind of traditional Japanese toilet; under which a night soil storage tank is prepared and the night soil is withdrawn and transported for treatment.
Waste Disposal and Public Cleansing Law
A law that stipulates regulations of management and disposal of all kinds of discharged wastes (excluding radioactive wastes and wastes polluted by radioactivity). It regulates the collection, transport and disposal of johkasou sludge withdrawn in the desludging of johkasou.
Water Pollution Control Law
A law that stipulates regulations on the discharge of wastewater from factories, buildings, etc. to public bodies of water using effluent standards; designed to promote domestic wastewater treatment to protect public bodies of water from water pollution.
