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Indicator · TLI ind_pm25_days_exceeding_who

Annual Count of Days Exceeding WHO Daily PM2.5 Guideline

จำนวนวันต่อปีที่ค่า PM2.5 เกินเกณฑ์มาตรฐานรายวันขององค์การอนามัยโลก

AS OF 18 MAY 2026 days/yr > WHO Weight 0.5

Source

OpenAQ (Pollution Control Department feed)

Crowd-sourced air-quality aggregator that ingests Thai PCD government sensor feeds and exposes a uniform API. Refresh: daily upstream; TLI re-pulls daily during burning season and weekly otherwise.

Goalposts

The 0-to-100 score for this indicator is normalized against fixed methodology goalposts. The values below define the band; click through to the methodology page for the framework that anchors them.

Score 100
30 days/yr > WHO
Score 0
300 days/yr > WHO
Direction
Lower is better
Anchor
Hybrid: international anchor and Thai distribution · WHO 2021 daily threshold (15 µg/m³ 24-hour)

The threshold for an exceedance day is the WHO 2021 24-hour guideline of 15 µg/m³. The score-100 floor at 30 days and the score-zero ceiling at 300 days are fitted to the observed Thai distribution. The 300-day ceiling was re-fit on 2026-04-30 from 200, where Bangkok (296 days) and Chiang Rai (200 days) clipped together with no within-bad-tier discrimination. The 30-day floor preserves a meaningful gap above zero.

Live distribution: 36 of 77 clip at the score-0 floor.

Which Thai province leads on Annual Count of Days Exceeding WHO Daily PM2.5 Guideline?

Phatthalung leads Thailand on Annual Count of Days Exceeding WHO Daily PM2.5 Guideline with a raw value of 82.6 days/yr > WHO, earning a TLI score of 80.5/100. The bottom of the distribution is Saraburi (358.4 days/yr > WHO, score 0/100).

Coverage

77 of 77 Thai provinces. Median score: 3.2. Each province's score is normalized 0–100 against fixed goalposts; a higher score is more favorable.

Reading the columns. Raw value the actual measurement in days/yr > WHO. Score normalized 0–100 against fixed methodology goalposts (not a percentile). Lower is better. Why ties? 36 share the score-0 floor at the lower goalpost. Provinces beyond the goalposts aren't separated further — that's the trade-off for fixed, year-over-year comparable scoring instead of percentiles.

Top scorers

Rank Province Raw value (days/yr > WHO) Score
1 Phatthalung 82.6 80.5
2 Trang 87.3 78.8
3 Narathiwat 102 73.3
4 Yala 111.5 69.8
5 Pattani 116.7 67.9

Lowest scorers

Rank Province Raw value (days/yr > WHO) Score
77 Saraburi 358.4 0
76 Kalasin 357 0
75 Phitsanulok 357 0
74 Ang Thong 355.7 0
73 Suphan Buri 355 0
Show all 77 provinces ranked Sorted highest to lowest score
Rank Province Raw value (days/yr > WHO) Score
1 Phatthalung 82.6 80.5
2 Trang 87.3 78.8
3 Narathiwat 102 73.3
4 Yala 111.5 69.8
5 Pattani 116.7 67.9
6 Si Sa Ket 124.1 65.1
7 Nakhon Si Thammarat 142.8 58.2
8 Krabi 144.9 57.4
9 Phuket 170.9 47.8
10 Phangnga 171.7 47.5
11 Ranong 184.3 42.9
12 Buri Ram 204.7 35.3
13 Satun 205 35.2
14 Chiang Rai 214.2 31.8
15 Khon Kaen 215.4 31.3
16 Songkhla 221.1 29.2
17 Roi Et 223.5 28.3
18 Amnat Charoen 226.6 27.2
19 Sakon Nakhon 231.6 25.3
20 Chumphon 235.4 23.9
21 Kanchanaburi 241.9 21.5
22 Nakhon Phanom 244.4 20.6
23 Surin 250.4 18.4
24 Nong Bua Lam Phu 250.8 18.2
25 Chaiyaphum 251.4 18
26 Nan 253 17.4
27 Phrae 254.7 16.8
28 Kamphaeng Phet 256.2 16.2
29 Rayong 262.1 14
30 Nakhon Pathom 265.9 12.6
31 Bueng Kan 268.1 11.8
32 Surat Thani 276 8.9
33 Nong Khai 279.4 7.6
34 Mukdahan 279.5 7.6
35 Samut Sakhon 285.2 5.5
36 Tak 289.4 3.9
37 Chiang Mai 290.5 3.5
38 Maha Sarakham 291.2 3.2
39 Nakhon Ratchasima 291.5 3.2
40 Yasothon 296.2 1.4
41 Samut Songkhram 297.6 0.9
42 Prachuap Khiri Khan 300.2 0
43 Mae Hong Son 304.1 0
44 Lopburi 311.1 0
45 Chanthaburi 311.8 0
46 Uthai Thani 315 0
47 Prachin Buri 317 0
48 Lampang 318.3 0
49 Bangkok 319.2 0
50 Udon Thani 320 0
51 Trat 322.2 0
52 Ubon Ratchathani 325.3 0
53 Nonthaburi 328.6 0
54 Phetchabun 330.6 0
55 Samut Prakan 331.1 0
56 Nakhon Nayok 331.9 0
57 Pathum Thani 332.6 0
58 Lamphun 332.9 0
59 Phetchaburi 333.3 0
60 Chachoengsao 334.1 0
61 Chon Buri 335.7 0
62 Loei 335.7 0
63 Chai Nat 340.5 0
64 Sa Kaeo 342 0
65 Sing Buri 343.8 0
66 Phichit 346.4 0
67 Nakhon Sawan 346.5 0
68 Sukhothai 348.7 0
69 Ratchaburi 350 0
70 Uttaradit 352.5 0
71 Phra Nakhon Si Ayutthaya 353.8 0
72 Phayao 354.4 0
73 Suphan Buri 355 0
74 Ang Thong 355.7 0
75 Phitsanulok 357 0
76 Kalasin 357 0
77 Saraburi 358.4 0

Methodology

See the methodology page for the full TLI scoring approach, including how this indicator's category Environment & Climate combines with the other six categories via geometric mean.

Cite as: "Annual Count of Days Exceeding WHO Daily PM2.5 Guideline." Thailand Livability Index, 2026. CC BY-NC 4.0.

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