XN000022-1994-11-16 — Page 20

18

WEDNESDAY, NOVEMBER 16, 1994

AIR QUALITY REPORT FOR OCTOBER

THE ENVIRONMENTAL PROTECTION DEPARTMENT RELEASED AIR QUALITY INFORMATION FOR LAST MONTH.

TODAY

(WEDNESDAY)

A SPOKESMAN FOR THE DEPARTMENT SAID THE PURPOSE OF THE ANNOUNCEMENT WAS TO KEEP THE PUBLIC INFORMED OF THE AIR QUALITY LEVELS IN THE TERRITORY AND TO EXPLAIN THE MEASUREMENTS.

THE ANNOUNCEMENT CONTAINS MONITORING RESULTS FROM MONG KOK, CENTRAL/WESTERN AND KWAI CHUNG, WHICH REPRESENT THREE IMPORTANT LAND USE TYPES IN THE TERRITORY:

* LOCATIONS CLOSE TO ROAD TRAFFIC IN BUILT-UP URBAN AREAS,

* COMBINED COMMERCIAL AND RESIDENTIAL DISTRICTS,

* DISTRICTS CLOSE TO INDUSTRIAL AREAS.

AT

THE DEPARTMENT CURRENTLY MONITORS AIR QUALITY CONTINUOUSLY EIGHT STATIONS, INCLUDING THE THREE MENTIONED. SHORT-TERM MEASUREMENT EXERCISES ARE ALSO UNDERTAKEN AS AND WHERE THE NEED ARISES.

THE REPORTED AIR POLLUTANTS INCLUDE SULPHUR DIOXIDE (802), NITROGEN DIOXIDE (NO2), TOTAL SUSPENDED PARTICULATES (TSP) WHICH COMPRISE ALL SIZES OF DUST PARTICLES, AND THE RESPIRABLE FRACTION OF THE DUST (RSP). ALL THESE POLLUTANTS CAN AFFECT RESPIRATORY HEALTH IN SUFFICIENT CONCENTRATION.

IN OCTOBER, TWO EXCEEDANCES OF THE 24-HOUR AIR QUALITY OBJECTIVES WERE RECORDED AT MONG KOK. TSP LEVELS WERE FOUND EXCEEDING OBJECTIVE ON OCTOBER 20 WHILE NO2 BREACHED ITS LIMIT ON OCTOBER

THE 28.

STRONG WIND ON OCTOBER 20 BLEW A LOT OF HEAVY SURFACE DUST INTO THE AIR. WHILE THIS CAUSED SIGNIFICANT AIR POLLUTANT CONCENTRATIONS AT ALL STATIONS, THE STREET LEVEL SITE AT MONG KOK MEASURED THE GREATEST INCREASE AS IT IS NEAREST TO THE SURFACE.

ON OCTOBER 28 WHEN NO2 LIMIT WAS BREACHED, SIGNIFICANT CONCENTRATIONS WERE MEASURED AT ALL THREE SITES. LOW WIND SPEEDS, ASSOCIATED WITH THE MEETING OF COLDER CONTINENTAL AIR AND WARMER MARINE AIR, RESULTED IN THE ACCUMULATION OF THIS VEHICLE RELATED

POLLUTANT.

OCTOBER.

IN GENERAL, SULPHUR DIOXIDE LEVELS WERE LOW AT ALL STATIONS

IN

THE GASES AND PARTICLES DESCRIBED ORIGINATED FROM VARIOUS SOURCES. S02 IS MOSTLY PRODUCED WHEN FUELS THAT CONTAIN SULPHUR ARE BURNED. NO2 IS FORMED DURING COMBUSTION BY THE COMBINATION OF NITROGEN AND OXYGEN.

/HOWEVER THE

Page 20Page 21