EPA Air · stack tests by state and year

Air-emissions stack tests in Ohio, 2024

• 2,721Stack tests

A stack test measures what a source actually emits, at the stack, against the limit in its permit. Every stack test below was recorded against a source in Ohio during 2024; one facility can appear more than once, because this is a record of what happened rather than a list of places.

Counties in Ohio, 2024

• Lucas County 340
• Monroe County 282
• Belmont County 257
• Harrison County 168
• Jefferson County 142
• Carroll County 141
• Montgomery County 127
• Guernsey County 97
• Cuyahoga County 85
• Noble County 83
• Butler County 82
• Columbiana County 72
• Tuscarawas County 71
• Hamilton County 67
• Undetermined County 51
• Wayne County 47
• Defiance County 40
• Stark County 39
• Franklin County 31
• Fayette County 31
• Ashtabula County 29
• Lorain County 29
• Erie County 27
• Mahoning County 27
• Licking County 26
• Perry County 24
• Fulton County 22
• Geauga County 18
• Summit County 17
• Paulding County 16
• Crawford County 15
• Greene County 14
• Scioto County 14
• Delaware County 13
• Brown County 12
• Wood County 11
• Allen County 10
• Darke County 9
• Trumbull County 9
• Lake County 8
• Coshocton County 8
• Washington County 8
• Shelby County 8
• Clark County 8
• Pickaway County 6
• Fairfield County 6
• Warren County 6
• Ashland County 6
• Jackson County 6
• Medina County 5
• Athens County 5
• Portage County 5
• Hancock County 5
• Richland County 5
• Lawrence County 4
• Ross County 4
• Union County 3
• Logan County 3
• Muskingum County 3

Ohio, other years

• 2026 1,474
• 2025 2,213
• 2023 2,800
• 2022 2,355
• 2021 2,582
• 2020 2,194
• 2019 2,684
• 2018 2,476
• 2017 2,537

Air-emissions stack tests recorded in Ohio, 2024

Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.