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The challenges have changed. So have we.

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Seeing the full system and improving it.

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Driving long-term value through responsible delivery.

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Emergency Response

Building readiness for decisive environmental action.

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Stack Testing

Accurate, EPA-compliant stack testing for industrial facilities.

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Leak Detection

Managing fugitive emissions in complex industrial facilities.

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Our Thinking Spotlight

The Onterris Outlook Report
NEW REPORT

The Onterris Outlook: Why Environmental Performance Is Business-Critical

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BRIEF

Federal Methane Rules in 2026: What Oil and Gas Operators Need to Do Now

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PERSPECTIVE

CCL 6 Is a Signal, Not a Standard. Why a Science-Forward Strategy Matters Now

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BRIEF

HON MACT Fenceline Monitoring Requirements

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Onterris is a global environmental solutions company partnering with organizations to solve complex challenges where environmental pressures, regulatory expectations and operational risks intersect.
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Solutions Testing & Analysis Stack Testing Power Start-Ups and Commissioning Source Testing

Power Start-Ups and Commissioning Source Testing

Getting new assets into compliance from day one
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INTRO

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

Data centers, utilities and other complex power projects depend on engines and turbines that must operate reliably and meet strict emissions requirements. Onterris helps commissioning teams verify performance, tune control systems and document initial compliance through source testing programs built for high-pressure go-live schedules. Our field teams deliver the data, coordination and technical testing support needed to move from start-up to acceptance with confidence.

Supporting Your Industry

Onterris supports facilities with stack testing programs that help teams document compliance, manage testing schedules and respond to complex requirements.

Chemical

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Manufacturing

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Energy

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Technology & Digital Infrastructure

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Infrastructure

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Solid Waste

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Mining & Minerals

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why it matters

Power start-up depends on proven emissions performance

Power start-up and commissioning schedules depend on reliable emissions data. When testing is delayed, incomplete or disconnected from operating conditions, projects can face turnover delays, compliance uncertainty and added pressure on engineering, operations and commissioning teams.
  • Avoid costly commissioning delays
  • Support aggressive go-live schedules
  • Verify performance before unit turnover
  • Fine tune controls with real-time emissions data
  • Meet initial compliance deadlines with confidence

Commissioning source testing for complex assets

Onterris provides emissions testing, diagnostic performance testing and performance verification for engines, gas turbines and related control systems during commissioning, start-up and acceptance programs. Our teams support data centers, utilities, power plants and other projects with field execution, source testing and documentation that help operators move from installation to operation with confidence.
Our capabilities
Gas turbine and engine initial compliance testing
Diagnostic testing during start-up and commissioning
Nitrogen oxides (NOx) and carbon monoxide (CO) testing
Concurrent testing across turbine and engine blocks
Initial compliance data packages
Temporary CEMS as a bridge during start-up

Related Services

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Testing & Analysis

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Environmental Laboratory Services

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Environmental Permitting, Air & Water Compliance Services

Working through air, water and land permitting requirements and building compliance programs that hold up under regulatory review, across regulated industries.
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Ambient Air Monitoring

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Elizabeth McGurk

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
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Blake Ericson

The Role of Stack Testing in OGMP 2.0 Gold Standard

Applying the power of FTIR stack testing to quantify methane slip and reconcile inventories with confidence
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Continuous Emissions Monitoring Systems: A Key Enabler of Permit Protection

Real-time emissions data does more than meet EPA requirements, it protects operations and strengthens compliance decisions
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Aerial view of an LNG tanker docked at a marine terminal, with support vessels alongside and turquoise coastal waters surrounding the port infrastructure.
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Leena Thomas

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.
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