Updated: 2025-12-15 02:25 CET

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Basic data		Locality photo
Locality:	Ondrejov
Code:	SONRA
Type of measuring programme:	Automated measuring program
Locality owner:	Czech Hydrometeorological Institute
Classification
Abbreviation:	B/R/N-REG
Localization
Coordinates:	49° 54´ 48.647" North latitude 14° 46´ 57.451" East longitude
Altitude:	514 m

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Actual measured level of air pollution

Actual unverified data

Date and time	Air quality	SO₂	NO₂	PM₁₀	O₃		PM₁₀ - from model	O₃ - from model
		3h average	3h average	3h average	3h average		3h average	3h average
		µg∙m⁻³	µg∙m⁻³	µg∙m⁻³	µg∙m⁻³		µg∙m⁻³	µg∙m⁻³
2025-12-14 00:00 - 03:00 CET	1A				14.5
2025-12-14 01:00 - 04:00 CET	1A				13.0
2025-12-14 02:00 - 05:00 CET	1A				10.8
2025-12-14 03:00 - 06:00 CET	1A				9.8
2025-12-14 04:00 - 07:00 CET	1A				9.7
2025-12-14 05:00 - 08:00 CET	1A				9.5
2025-12-14 06:00 - 09:00 CET	1A				9.8
2025-12-14 07:00 - 10:00 CET	1A				13.0
2025-12-14 08:00 - 11:00 CET	1A				16.5
2025-12-14 09:00 - 12:00 CET	1A				21.0
2025-12-14 10:00 - 13:00 CET	1A				25.7
2025-12-14 11:00 - 14:00 CET	1A				30.5
2025-12-14 12:00 - 15:00 CET	1A				30.6
2025-12-14 13:00 - 16:00 CET	1A				27.2
2025-12-14 14:00 - 17:00 CET	1A				23.6
2025-12-14 15:00 - 18:00 CET	1A				22.2
2025-12-14 16:00 - 19:00 CET	1A				21.3
2025-12-14 17:00 - 20:00 CET	1A				19.6
2025-12-14 18:00 - 21:00 CET	1A				18.5
2025-12-14 19:00 - 22:00 CET	1A				17.7
2025-12-14 20:00 - 23:00 CET	1A				17.5
2025-12-14 21:00 - 00:00 CET	1A				16.9
2025-12-14 22:00 - 01:00 CET	1A				16.5
2025-12-14 23:00 - 02:00 CET	1A				16.0

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Legend

Level	Index range	Air quality
1A	≥ 0.00 and < 0.34	very good to good
1B	≥ 0.34 and < 0.67
2A	≥ 0.67 and < 1.00	acceptable
2B	≥ 1.00 and < 1.50
3A	≥ 1.50 and < 2.00	aggravated to bad
3B	≥ 2.00
	Component is not measured, index not determined
	Incomplete data

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Map of station position

Map is on page with detailed information about locality