What is backflow in a plumbing system?
Correct Answer
B) Reversal of flow that can contaminate potable water
Backflow reverses the intended flow direction. Across a cross-connection it can introduce contamination into potable water through backpressure or backsiphonage. Normal drainage, HVAC airflow and water hammer describe different phenomena. Source: https://www.epa.gov/sites/default/files/2015-09/documents/2007_05_18_disinfection_tcr_issuepaper_tcr_crossconnection-backflow.pdf
Why This Is the Correct Answer
Backflow reverses the intended flow direction. Across a cross-connection it can introduce contamination into potable water through backpressure or backsiphonage. Normal drainage, HVAC airflow and water hammer describe different phenomena. Source: https://www.epa.gov/sites/default/files/2015-09/documents/2007_05_18_disinfection_tcr_issuepaper_tcr_crossconnection-backflow.pdf
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