What is “PM10”?
PM10 is a measurement unit for dust particles present in the air. In technical terms, PM10 means Particulate Matter with diameter less than or equal to 10 micrometer. Its measurement unit is microgram per cubic meter.

What are the types of air quality?
There are five levels of air quality depending upon the amount of dust. They are as follows:

Where are the air quality stations?
Air Quality of Kathmandu Valley is recorded at six stations daily, but the data is compiled on a weekly basis. The six stations are Putali Sadak, Matsyagaon, Tribhuvan University, Bhaktapur, Patan Hospital and Thamel.

Ministry of Environment and Population runs the stations under the assistance of Danish agency, Danida.   

Valley air improves                                                                                                                      What is PM10 ?

The air quality of Kathmandu valley improved from January 20 to 26 as compared to the previous period. During the period, five of six monitoring stations recording a fall in pollution levels, according to the data recorded by the Ministry of Environment and Population.

The weekly averages of the air pollution levels (based on the daily averages) showed a decrease in the monitoring stations at Putalisadak, Matsyagaon, Kirtipur (Tribhuvan University area) Bhaktapur and Patan Hospital area while weekly averages at Thamel showed an increase.

Weekly air quality report : February 20- February 26

Date	Putalisadak	Matsyagaon	Kirtipur	Bhaktapur	Patan Hospital	Thamel
2005/02/20	426	58	81	197	417	213	235
2005/02/21	319	52	98	147	323	225	195.5
2005/02/22	218	38	71	133	285	132	146.16
2005/02/23	212	26	40	76	116	99	94.83
2005/02/24	247	38	67	117	217	165	141.83
2005/02/25	222	34	54	116	238	156	136.66
2005/02/26	179	49	74	105	236	134	129.50
	260.42	42.14	69.28	127.20	236.14	163.14	154.21

( * The Kathmandu Valley Weekly Average data is compiled by Nepalnews. Other data obtained from the Ministry of Population and Environment).    

The Patan Hospital area and the Matsyagaon area were the most and least polluted sites in the Valley during the period. The Patan Hospital area recorded a weekly average (based on the daily averages) of 263.14 PM10, down from the previous week’s 278 PM10. The area recorded ‘very unhealthy’, ‘moderate’ and 'unhealthy' air marks a day each and five days of the period respectively.

The Matsyagaon area recorded 'good' air marks for entire period with a weekly average of 42.14PM10. The Matsyagaon area had recorded 56 PM10 in the last period.

The Putalisadak, Thamel, Bhaktapur and Kirtipur area were respectively the second, third and fourth most polluted sites in the Valley during the period recording a weekly average of 260.42, 163.14, 127.20, and 69.28 PM10 respectively.

According to the data recorded by the Ministry of Environment and Population, the overall outdoor air quality of Kathmandu valley on Wednesday (March 02) was “unhealthy” recording 168 pgm/m3

Weekly air quality report : February 13- February 19

Date	Putalisadak	Matsyagaon	Kirtipur	Bhaktapur	Patan Hospital	Thamel
2005/02/13	315	44	79	137	265	127	161.17
2005/02/14	272	53	92	117	305	147	164.33
2005/02/15	260	59	126	170	371	169	192.50
2005/02/16	368	78	116	136	254	176	188.00
2005/02/17	337	73	99	164	274	188	189.17
2005/02/18	374	37	66	108	216	131	155.33
2005/02/19	257	48	83	137	261	146	155.33
	311.86	56.00	77.86	138.43	278.00	154.86	169.50

( * The Kathmandu Valley Weekly Average data is compiled by Nepalnews. Other data obtained from the Ministry of Population and Environment). nepalnews.com pd Mar 03 05    

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Valley air quality monitoring shows mixed results                                          What is PM10 ?  

The air quality of the Kathmandu Valley, from February 06 to 12, showed mixed results as compared to the previous period, according to the data recorded by the Ministry of Environment and Population.

The weekly averages of air pollution (based on the daily average) increased in Putalisadak, Matsyagaon, Kirtipur, Bhaktapur and Patan hospital area, while it decreased in the Thamel area.

Weekly air quality report : February 06 - February 12

Date	Putalisadak	Matsyagaon	Kirtipur	Bhaktapur	Patan Hospital	Thamel
2005/02/06	279	47	83	134	272	177	165.33
2005/02/07	311	64	116	158	365	199	202.16
2005/02/08	374	59	135	173	347	204	215.33
2005/02/09	267	47	102	161	288	161	171
2005/02/10	258	36	87	143	277	170	161.83
2005/02/11	260	38	88	148	265	151	158.33
2005/02/12	282	36	56	133	299	142	158
	290.14	46.71	95.28	150	301.85	172	175.99

( * The Kathmandu Valley Weekly Average data is compiled by Nepalnews. Other data obtained from the Ministry of Population and Environment).    

During the period, the Patan hospital area was the most polluted site while the Matsyagaon area was the least polluted. The Patan hospital area recorded a weekly average (based on the daily averages) of 301.85 PM10. The area recorded “very unhealthy” and “unhealthy” and air marks for one and six days of the period respectively.

The Matsyagaon area recorded “moderate” and “good” air marks for one and six days of the period respectively, according to the data.

The Putalisadak, Thamel, Bhaktapur and Tribhuvan University area (Kirtipur) were second, third and fourth most polluted sites in the Valley during the period recording a weekly average of 290.14, 172, 150 and 95.28 PM10 respectively.

The Ministry of Environment and Population, monitors air pollution levels in six different stations of Kathmandu valley and publishes the results weekly on its web site.nepalnews.com pd Feb 17 05

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Jan 2005 Mope

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