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MARCH AIR QUALITY REPORT
WEDNESDAY, APRIL 13, 1994
THE ENVIRONMENTAL PROTECTION DEPARTMENT (EPD) TODAY (WEDNESDAY} RELEASED AIR QUALITY INFORMATION FOR LAST MONTH,
A SPOKESMAN FOR THE ANNOUNCEMENT WAS TO KEEP THE
DEPARTMENT SAID THE PURPOSE OF THE PUBLIC INFORMED OF THE AIR QUALITY LEVELS IN THE TERRITORY AND TO EXPLAIN THE MEASUREMENTS.
THE ANNOUNCEMENT CONTAINS MONITORING RESULTS FROM MONG кок, CENTRAL/WESTERN AND KWAI CHUNG. THESE LOCATIONS ARE TYPICAL OF THE IMPORTANT LAND USE TYPES FOUND IN THE TERRITORY:
OF THREE
LOCATIONS CLOSE TO ROAD TRAFFIC IN BUILT-UP URBAN AREAS, * COMBINED COMMERCIAL AND RESIDENTIAL DISTRICTS, AND
DISTRICTS CLOSE TO INDUSTRIAL AREAS.
AT
THE DEPARTMENT CURRENTLY MONITORS AIR QUALITY CONTINUOUSLY EIGHT STATIONS, INCLUDING THE THREE MENTIONED. SHORT-TERM MEASUREMENT CAMPAIGNS ARE ALSO UNDERTAKEN AS AND WHERE THE NEED ARISES.
THE REPORTED AIR POLLUTANTS INCLUDE SULPHUR DIOXIDE (SO2), NITROGEN DIOXIDE (NO2), TOTAL SUSPENDED PARTICULATES (TSP) WHICH COMPRISE ALL SIZES OF DUST PARTICLES, AND RESPIRABLE SUSPENDED PARTICULATES (RSP) WHICH ARE THE RESPIRABLE FRACTION OF THE DUST.
ALL THESE POLLUTANTS CAN AFFECT RESPIRATORY HEALTH IN
SUFFICIENT CONCENTRATION.
IN MARCH, THERE WERE NO EXCEEDANCES OF THE AIR QUALITY OBJECTIVES AT ANY OF THE THREE STATIONS AND LEVELS OF POLLUTANTS WERE RELATIVELY CONSTANT THROUGHOUT THE MONTH. AS USUAL, POLLUTANT LEVELS WERE HIGHER AT THE STREET LEVEL SITE OF MONG KOK THAN AT THE OTHER TWO ROOF-TOP SITES.
NITROGEN DIOXIDE LEVELS WERE HIGH AT MONG KOK FOR MOST
THE MONTH. THE 24-HOUR AVERAGE WAS ABOVE 100UG/M3, TWO-THIRDS OF THE AIR QUALITY OBJECTIVE VALUE, FOR 25 OUT OF THE 31 DAYS IN THE MONTH. ON MARCH 3, AMBIENT LEVELS EQUALLED THE LIMIT.
THESE HIGH DAILY VALUES PRODUCED A MONTHLY AVERAGE NO2 CONCENTRATION THAT WAS THREE TIMES THE LEVEL RECORDED
IN MARCH LAST
YEAR.
SULPHUR DIOXIDE LEVELS AT THE SITE WERE TWICE THE 1993 LEVEL BUT DUST LEVELS WERE ONLY SLIGHTLY HIGHER.
ROADWORKS NEAR THE SITE HAVE BEEN FINISHED AND THERE IS NOW AN INCREASED FLOW OF TRAFFIC. EXHAUST EMISSIONS FROM THIS EXTRA TRAFFIC ARE THOUGHT TO BE THE CAUSE OF THE OBSERVED INCREASES.
AVERAGE DUST LEVELS AT 30-50 PER CENT GREATER THAN RAINFALL WAS 50 PER CENT LESS
CENTRAL/WESTERN AND LAST YEAR. THIS IS THAN IN MARCH 1993.
KWAI CHUNG WERE PROBABLY BECAUSE
/HENCE, THERE