Is a closed-loop system legally required for hydrocarbon extraction?

Yes, in virtually every licensed cannabis and botanical processing jurisdiction. Fire codes, including NFPA 1 and applicable state regulations, require that hydrocarbon extraction equipment operate as a closed-loop system housed inside a Class I, Division 1 (C1D1) rated room. These requirements exist because butane, propane, and isobutane are flammable gases that can form ignitable vapor concentrations if released into an enclosed space.

What does C1D1 mean and why does it matter for extraction?

Class I, Division 1 (C1D1) is a hazardous location electrical classification defined in the National Electrical Code (NFPA 70). It designates spaces where ignitable concentrations of flammable gas or vapor may be present continuously or intermittently under normal operating conditions. Every electrical device installed in a C1D1-classified extraction room — including the extractor's own controls, interface, and vacuum components — must be specifically rated and certified to operate without producing an ignition source in that environment.

What is a Pressure Safety Inspector review and do I need one?

A Pressure Safety Inspector (PSI) is a credentialed engineer who evaluates whether a pressurized system's design, operating conditions, relief device settings, and materials are safe for the intended application. PSI review is distinct from a regulatory permit inspection; it is an engineering-level assessment that provides documented evidence that the system has been scrutinized by a qualified third party. Many jurisdictions, insurance carriers, and facility operators require PSI documentation before allowing a hydrocarbon extraction system to begin operations, and Decimal's HX line carries this review as a standard feature.

What documentation should I request before buying a closed-loop hydrocarbon extractor?

Before purchasing, request pressure vessel certification documents (confirming ASME code construction if applicable), electrical classification certifications for all components installed inside the classified space, Pressure Safety Inspector review records, pressure relief device sizing documentation, and material compatibility confirmation for all seals and gaskets in solvent contact. A manufacturer that cannot provide these documents is selling a system that may not pass your jurisdiction's inspection or satisfy your insurance carrier's requirements.

Closed-Loop Extraction Systems Explained: How They Work

Q: What makes an extraction system truly closed-loop?

A closed-loop extraction system routes solvent through a fully sealed, pressure-rated circuit — from storage tank through material columns into collection vessels and back — without venting to the surrounding atmosphere during a normal run. The defining characteristic is that no solvent escapes the sealed pathway under operating conditions, which both prevents flammable vapor accumulation in the room and allows solvent to be recovered and reused each cycle.

Learn what makes an extraction system truly closed-loop, why fire codes require it for hydrocarbon solvents, and what to verify before buying — ASME, C1D1, PSI review.