The HON Rule: Why Pilot Studies Matter

As chemical manufacturers prepare for the sweeping monitoring, reporting, and compliance requirements introduced by the updated Hazardous Organic NESHAP (HON) Rule, pilot studies are crucial for compliance. These small‑scale programs give facilities the opportunity to evaluate monitoring workflows, validate sampling procedures, strengthen data management, and uncover operational blind spots long before formal deadlines arrive.

In a previous post, we unpacked what the rule is, who it applies to, and the core requirements. Let’s take a deeper dive into why pilot studies are becoming one of the most valuable tools for HON Rule compliance.

What is a Pilot Study?

A pilot study is a controlled, short‑term trial that allows a facility to test key monitoring, sampling, reporting, and operational readiness steps before they are legally required to comply. With the HON Rule mandating continuous emission monitoring, routine reporting, and emissions limits for approximately 220 U.S. chemical facilities, pilot studies give teams a low‑risk environment to test processes and technologies ahead of deadlines.

Why Pilot Studies Are So Valuable Under the HON Rule

Identify Gaps in Operational Readiness

Under the updated HON Rule, facilities face tighter requirements for emission sources, flare systems, heat exchangers, equipment leaks, and startup/shutdown operations.

A pilot enables facilities to:

• Test sampling collection and procedures
• Verify that continuous monitoring systems integrate correctly
• Evaluate whether equipment meets updated MACT standards

By running trial scenarios, teams can uncover opportunities to strengthen compliance readiness, pinpoint calibration issues, and determine necessary capital upgrades well ahead of regulatory deadlines.

Build Cross‑Functional Preparedness

Multiple departments—including health and safety, operations, engineering, and laboratory partners—collaborate under the HON Rule. Pilot studies create a structured, cross‑team rehearsal that:

• Clarifies roles and responsibilities
• Ensures staff understand new monitoring protocols
• Highlights training needs, documentation gaps, or unclear procedures

This team‑level clarity becomes especially important given the scope and complexity of new monitoring obligations under the regulation.

Reduce Costs

Without pilot studies, facilities run the risk of increased costs down the road.

Pilot studies give facilities the time to:

• Budget for capital projects and expenses
• Avoid costly, last‑minute changes

Acting early helps prevent monetary bottlenecks and improves long‑term compliance resilience.

How to Structure an Effective HON Rule Pilot Study

Here’s a recommended framework for facilities looking to begin:

1. Define the scope
   Decide whether your pilot will focus on:
   • Monitoring setup
   • Sampling and laboratory testing
   • Internal reporting processes
   • Combination of all the above
2. Select representative monitoring locations
   Ensure pilot sample sites mimic future regulatory siting requirements.
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   • Bulleted Sub-item D
3. Conduct limited‑duration sampling
   Use both passive sorbent tubes and canister-based testing to simulate real data collection of all the compounds within the regulation.
4. Process data through your intended reporting workflow
   Run emissions calculations, QA/QC checks, and mock CEDRI submissions.
5. Evaluate outcomes
   Document what worked, what didn’t, and what must change before full implementation.
6. Scale to full compliance
   Use pilot findings to drive long‑term planning to ensure success when the rule goes into effect.

The Bottom Line: Pilot Studies Jumpstart HON Compliance

The new HON Rule represents one of the most significant shifts in hazardous air pollutant monitoring and control in recent years. But it doesn’t have to be overwhelming. Pilot studies let facilities test, learn, adjust, and build competence early—transforming compliance from a stressful deadline into a manageable, predictable process.

Pace® continues to support chemical manufacturers as they prepare for every phase of the HON Rule. If you’d like help designing or executing a HON Rule pilot study, our technical experts are ready to assist.