1. Method of Determination: USEPA Method T09: Method for the Determination of Polychorinated Dibenzo-p-Dioxins (PCDDs) in Ambient Air using High-Resolution Gas Chromatography/High-Resolution Mass Spectrometry (HRGC/HRMS)
2. The Total 2,3,7,8-TCDD Toxicity Equivalence is the product sum of the concentration of all seventeen 2,3,7,8-substituted PCDDs/PCDFs congeners and their respective Toxicity Equivalence Factor (TEF). For those congeners with concentration found below the method detection limit (MDL). half MDL is used for calculation.
3. Result for Jan. 2003 was not available because of test failure.
4. No monitoring results for Oct., Nov. and Dec. 2010 because incineration system was shut down for upgrade works.
5. No monitoring result for Dec. 2012 because incineration system was shut down for overhaul.
6. Ambient air samples for Jan. to May 2013 were taken at the adjacent Ching Wai House because Ching Yung House was under renovation works.
7. No monitoring result for June 2015 because incineration system was shut down for maintenance.
8. Dioxins samples are collected for analysis by an accredited laboratory every month. The analytical work will usually take several weeks. The Environmental Protection Department will post the data on the website once the report is available.
9. Regarding the ambient dioxins monitoring results, the Environmental Protection Department (EPD) will conduct data verification on the data submitted by the CWTC and then compile all the monitoring results, including dioxins, SOx and NOx, etc, in a detailed report for submission to the Community Affairs Committee of the Kwai Tsing District Council for information on a regular basis. Owing to the time for data verification and report compilation, the release of data and submission of report would normally be after a lapse of several months from the sampling date. To expedite the release of ambient dioxins level, EPD has separately handled the release of the ambient dioxins monitoring results and the report to Kwai Tsing District Council since November 2019 with a view to publishing the ambient dioxins data as soon as possible.