Since the outbreak of the pandemic, China has attached great importance to epidemic prevention and control. Apart from standardizing personal protective measures, stringent regulatory standards have also been imposed on medical institutions. Medical wastewater treatment has long been a critical challenge for hospitals. Standardized emergency monitoring protocols for medical wastewater at pandemic-related medical facilities have been vigorously implemented. This article briefly elaborates on the regulatory requirements for medical wastewater discharge and monitoring.

Requirements for Medical Wastewater Monitoring

Self-monitoring In accordance with regulatory documents issued by ecological and environmental authorities, including the Emergency Monitoring Plan for the Response to COVID-19 and the Discharge Standard of Water Pollutants for Medical Institutions, relevant facilities shall conduct automatic monitoring of wastewater discharge. The frequency of testing for total residual chlorine in wastewater shall be increased. Daily single monitoring is insufficient for designated medical institutions, and dedicated fever clinics and isolation observation sites shall also complete routine self-monitoring.

Beyond total residual chlorine, pandemic-affected facilities shall conduct testing for all pollutant indicators specified in the Discharge Standard of Water Pollutants for Medical Institutions, following the below frequency standards:

• pH value at discharge outlets: no fewer than two tests per day
• Chemical Oxygen Demand (COD) and Suspended Solids (SS): one test per week
• Other pollutant indicators: no fewer than one test per quarter
• Coliform bacteria: no fewer than one test per month

Facilities shall install dedicated monitoring equipment for total residual chlorine and connect such devices to the ecological environmental cloud platform. Designated medical institutions shall also accelerate the installation of Online Coliform Analyzers.

Manual on-site monitoring Wastewater sampling and testing shall adopt on-site rapid detection or field inspection methods; sample delivery to off-site laboratories for testing is prohibited. Sampling and monitoring operations shall be carried out under the guidance of professionals from health and disease control departments or hospital management teams.

Regulatory Standards for Medical Wastewater Discharge

Prior to discharge, all pollutant indicators of disinfected medical wastewater shall comply with the requirements set forth in the Discharge Standard of Water Pollutants for Medical Institutions.

• For wastewater discharged into municipal sewer networks: total residual chlorine content shall stay below 10 mg/L.
• For wastewater directly discharged into natural water bodies: total residual chlorine content shall stay below 0.5 mg/L.

If the total residual chlorine concentration at the wastewater discharge outlet exceeds the specified thresholds, targeted dechlorination treatment shall be implemented as needed. This avoids ecological damage and health risks caused by excessive chlorine in discharged effluent. Additionally, the concentration of coliform bacteria in wastewater shall be controlled below 100 CFU per liter.