Quality ControlSewerage Quality control


The Sewerage Quality Control Laboratory (Sewerage Laboratory) of EYATH S.A. is accredited to ISO/IEC 17025:2017 by the Hellenic Accreditation System – E.SY.D (Certificate No. 1139-4).

The official Scope of Accreditation of the Sewerage Laboratory (Annex F1/7 to E.SY.D Certificate No. 1139-4) includes the determination of various parameters related to the monitoring of the operation of Wastewater Treatment Facilities and the Waste Treatment Plant, and of the discharge from activities generating liquid waste, as indicated in the below Table.

The Quality Policy of the EYAH S.A. Sewerage Laboratory requires, inter alia, that activities and tests always be carried out in a proper and scientific manner, which ensures independent judgement, impartiality, integrity and confidentiality.

Every year the Sewerage Laboratory participates in programmes involving interlaboratory comparisons and proficiency testing, where it successfully meets the requirements, thus establishing the reliability of its measurements.


Samples of liquid waste – wastewater:

  • from Wastewater Treatment Facilities ,
  • from the Waste Treatment Plant,
  • activities producing liquid industrial waste, and
  • in cases of leaks and/or at the request of citizens (application form), and following payment of the corresponding fee.

are taken on site and are analysed by the Department employees at the EYATH S.A. Sewerage Laboratory (permanent facilities at 98 Tsimiski Street, 8th floor).

Materials/Products subjected to tests Types of tests/Measured properties Applied methods/ Techniques used
Chemical tests
Liquid waste/Wastewater

Determination of pH In-house method based on ΕLΟΤ 658/1983

Method Code: ΜΑ-01

Determination of Total Suspended Solids (ΤSS) In-house method based on 2540 D APHA (24rd Ed., 2023)

Method Code: ΜΑ-02

Determination of Chemical Oxygen Demand (COD) Merck 1.14540.0001 and


Determination of ΝΗ4-N (Ammonium Nitrogen) Merck 1.14558.0001

and 1.14559.0001

Determination of ΝΟ3-N

(Nitrate Nitrogen)

Merck 1.14563.0001
Determination of Total Nitrogen (ΤΝ) Merck 1.00613.0001

and 1.14763.0001

Determination of Total Phosphorous (TP) Merck 1.14729.0001
Determination of True Color (TC) In house method based on 2120 C APHA (24rd Ed., 2023)
Wastewater Determination of Biological Oxygen Demand (ΒOD5) In-house method based on 5210 B APHA (24rd Ed., 2023) Κωδικός Method Code: ΜΑ-08

Issuance of Results

EYATH S.A. customers can request the results of the sample(s) of liquid waste/wastewater taken by EYATH S.A. by filling in and submitting the relevant form, and by paying the corresponding fee.

Environmental Legislation

The required special conditions for the disposal of liquid waste – wastewater are determined by the legislation:

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