Air Quality and Emissions Testing You Can Trust
Comprehensive stack testing, leak detection, ambient air monitoring and laboratory services combine to deliver air quality data that regulators trust and organizations rely on.
Comprehensive air quality services from source to solution
Onterris combines stack testing, leak detection, ambient air and fenceline monitoring with in-house laboratory capabilities to deliver the accurate environmental data you need for operational confidence.
End-to-end emissions expertise for any environmental challenge
Why certainty matters with your air quality program
Confident environmental decisions depend on reliable, defensible data. Poor or incomplete air quality testing creates uncertainty, disrupts operations and increases regulatory exposure. Partnering with Onterris gives you peace of mind.
Defensible air emissions data that holds up to regulatory scrutiny
Consistent methods across facilities and jurisdictions
Help with navigating increasing pressure from regulators, communities and stakeholders
A single, comprehensive partner across emissions testing, monitoring and lab analysis
Deep expertise and insight into constantly changing air quality requirements
All of your emissions data, visible and connected in one place
Leading organizations trust us with their air quality compliance
Across complex operations, we help execute air quality programs that deliver measurable improvements in compliance, efficiency and decision-making.
Designing the Future of Methane Measurement for Natural Gas Facilities
See how Onterris validated a faster, cost-effective and field-ready method for measuring methane slip in natural gas engines with high accuracy and scalability for real-world operations.
Turning fenceline data into community confidence for Phillips 66
Onterris helped Phillips 66 develop a real-time fenceline monitoring and reporting program to meet Colorado’s fenceline mandate and strengthen public trust
The Onterris team are true experts and have been willing to roll-up their sleeves to create customized solutions to solve our most complex air quality challenges.
Yousaf Hameed, Principal, Air Quality Planning, Clark County
Explore the latest air quality resources
Federal Methane Rules in 2026: What Oil and Gas Operators Need to Do Now
Operators that act on measurement, documentation and system readiness now will strengthen performance and stay ahead of compliance
LNG Methane Emissions Measurement & Monitoring
Learn how direct methane measurement across LNG loading, shipping and unloading helps operators strengthen emissions data, compliance and market access.
A Smarter Approach to Methane Management in Wastewater Treatment Plants
With better visibility into emissions, operators can act on high-impact leaks, reduce odor and strengthen maintenance outcomes
PFAS in Air: New EPA Testing Methods Reshape Emissions Management
What methods like OTM-45 and OTM-50 mean for the future of PFAS in air regulation
Air Permitting for Data Centers: What Determines Your Timeline
How location, power generation and the regulatory landscape affect data center air permits
HON MACT Fenceline Monitoring Requirements
Understand HON MACT fenceline monitoring requirements, EPA Methods 325A/325B and 327, and how real-time monitoring supports faster emissions response.
Appendix K Certification: Why OGI Compliance Demands Expertise and Discipline
The technical standard that determines whether your methane emissions data withstands regulatory scrutiny
Take the next step with air quality data you can stand behind
From stack testing and leak detection services to ambient air monitoring and advanced lab analysis, our experts help organizations replace uncertainty with clarity.
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