Synthetic organic chemical plants face the fastest-moving LDAR landscape in the country right now. The 2024 HON amendments rewrote the rules — new fenceline monitoring for six air toxics, tighter standards on equipment leaks, and the end of startup, shutdown, and malfunction exemptions. AIM™ EH&S runs Leak Detection and Repair (LDAR) at chemical plants with crews who have walked the units they monitor.
Which Rules Apply at Chemical Plants
SOCMI equipment leaks fall under NSPS Subpart VV/VVa and the Hazardous Organic NESHAP (HON — 40 CFR 63 Subparts F, G, H, and I). The May 2024 HON amendments added fenceline monitoring for ethylene oxide, chloroprene, benzene, 1,3-butadiene, ethylene dichloride, and vinyl chloride, with tight action levels (0.2 µg/m³ for ethylene oxide; 0.8 µg/m³ for chloroprene, 0.3 at neoprene plants) and most monitoring beginning July 15, 2026. We map the applicable subpart and the new fenceline obligations to your actual equipment instead of guessing.
What We Do
Method 21 component monitoring, OGI surveys where allowed, fenceline monitor siting and baseline sampling, repair tracking against the regulatory clock, recordkeeping that survives an inspection, and program design — from a single process unit to plant-wide component counts. With the 2026 fenceline deadline closing in, we get inventory and baselines underway now.
Why Chemical Operators Call Us
Deep familiarity with SOCMI rules and the 2024 HON changes, calibrated instruments, and defensible data every time. We read the new fenceline requirements the way an inspector will. No fluff, no padded headcounts.
Chemical Plant LDAR FAQs
What changed under the 2024 HON amendments?
The 2024 Hazardous Organic NESHAP (HON) rewrite added fenceline monitoring for six air toxics — including ethylene oxide and chloroprene — tightened leak definitions, and removed several exemptions. Many SOCMI units face a July 15, 2026 compliance date. See our LDAR compliance overview.
Which rules apply to chemical plant equipment leaks?
Synthetic organic chemical manufacturing (SOCMI) units fall under the HON and NSPS VV/VVa, plus applicable state programs. We read the controlling subpart for your process units instead of guessing.
How does the new chemical fenceline monitoring work?
Passive samplers around the unit perimeter are collected on a fixed cycle and averaged against per-pollutant action levels; exceedances trigger root-cause analysis and corrective action. We handle siting, chain of custody, lab QA, and reporting.
Do you cover cooling-tower and heat-exchange monitoring too?
Yes — we run Modified El Paso Method monitoring of cooling-water systems for VOC leaks, a common companion requirement at chemical plants.
Can you train our team to run the program?
Yes. We offer LDAR & Method 21 training for technicians and supervisors — on your site, on your equipment.
Which regions do you cover?
Nationwide, with strong coverage along the Gulf Coast, Texas, and Louisiana. See all regions we serve.
Get Ahead of the 2026 Fenceline Deadline
The HON clock is already running. Talk to someone who has walked the unit.
Two tools that keep chemical plants ahead of the rule
The same regulatory engine we run for clients, put in your hands.