Accurate, EPA-compliant stack testing for industrial facilities.

Stack Testing and Source Emissions Testing Services

why it matters

Stack testing that stands up to scrutiny

• Tightening federal, state and local requirements
• Data that holds up to regulatory scrutiny and audits
• Consistent methods across facilities and vendors
• Lower risk from delayed or uncertain results

Keep Data Center Start-ups On Track With Onterris

Onterris combines air permitting, stack testing and ongoing emissions support through one coordinated team, helping owners, developers and operators bring data centers online quickly, maintain compliance and operate efficiently throughout their lifecycle. Learn more.

Delivering Accurate Emissions Data to Support Compliance and Operational Confidence

Onterris helps clients plan, execute and document stack testing programs that generate defensible emissions data, support regulatory compliance and inform operational decision-making across routine and complex source testing scenarios.

Client Challenges We Solve

Emissions Compliance Testing

Verifying compliance with accurate stack testing data

Temporary CEMS and FTIR Emissions Monitoring

Delivering real-time emissions insight for complex compliance programs

Power Start-Ups and Commissioning Source Testing

Accelerating complex start-up and commissioning projects with defensible emissions data

Engine, Boiler & Combustion Source Testing

Optimizing combustion performance with defensible emissions data

Data Center Emissions Compliance

Keep data center start-ups on track

Pulp, Paper & Wood Products Stack Testing

Stack testing that keeps your facility moving