Updated: 2026-04-04 18:25 CEST

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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
2026-04-03 16:00 - 19:00 CEST	2A				85.4
2026-04-03 17:00 - 20:00 CEST	2A				85.5
2026-04-03 18:00 - 21:00 CEST	2A				84.6
2026-04-03 19:00 - 22:00 CEST	2A				84.1
2026-04-03 20:00 - 23:00 CEST	2A				82.3
2026-04-03 21:00 - 00:00 CEST	2A				80.7
2026-04-03 22:00 - 01:00 CEST	2A				78.3
2026-04-03 23:00 - 02:00 CEST	2A				75.1
2026-04-04 00:00 - 03:00 CEST	2A				72.9
2026-04-04 01:00 - 04:00 CEST	2A				72.8
2026-04-04 02:00 - 05:00 CEST	2A				73.7
2026-04-04 03:00 - 06:00 CEST	2A				76.4
2026-04-04 04:00 - 07:00 CEST	2A				77.1
2026-04-04 05:00 - 08:00 CEST	2A				75.9
2026-04-04 06:00 - 09:00 CEST	2A				74.2
2026-04-04 07:00 - 10:00 CEST	2A				72.7
2026-04-04 08:00 - 11:00 CEST	2A				71.3
2026-04-04 09:00 - 12:00 CEST	1B				69.4
2026-04-04 10:00 - 13:00 CEST	1B				68.2
2026-04-04 11:00 - 14:00 CEST	1B				67.5
2026-04-04 12:00 - 15:00 CEST	1B				67.4
2026-04-04 13:00 - 16:00 CEST	1B				67.4
2026-04-04 14:00 - 17:00 CEST	1B				68.1
2026-04-04 15:00 - 18:00 CEST	1B				68.1

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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