Dust Hazard Analysis (DHA) for Plastics, Resins, and Regrind

By DHA Report Group · Updated October 20, 2026

Plastics plants tend to think of themselves as pellet operations, and pellets are not much of a dust hazard. The dust shows up everywhere else: fines that break off in pneumatic conveying, powder resins and additives, grinder and regrind areas, and trimming or machining of finished parts. Many of those are combustible dusts, and your dust hazard analysis (DHA) needs to find them.

Where the dust comes from

• Pellet fines and streamers from pneumatic conveying, especially at bends and high velocities
• Powder resins like PVC, polyethylene powder, and nylon powder
• Additives and fillers including pigments, stabilizers, and some flame retardants
• Regrind and granulator dust from grinding scrap and rejects
• Machining, routing, and trimming dust from finished parts
• Rotational molding and powder coating powders

Why static matters so much

Plastic particles moving through ducts, hoses, and hoppers build static charge quickly. A spark from an ungrounded hose, a plastic liner, a person, or a portable container can be enough to ignite a dust cloud. That makes grounding and bonding one of the most important parts of a plastics DHA.

Where a DHA looks in a plastics plant

• Silos, railcar and truck unloading, and bulk bag stations
• Pneumatic conveying lines, loaders, and receivers
• Dryers and blenders
• Granulators and regrind handling
• Dust collectors and elutriators (fines separators)
• Compounding and extrusion areas where powders are added
• Finishing areas with sanding, routing, or trimming
• Solvents nearby that could create a hybrid mixture with dust

Common gaps in plastics facilities

• Ungrounded conveying hoses, flexible connections, and portable containers
• Fines building up in collectors and elutriators with no explosion protection
• Granulators without dust control, spreading regrind dust across the room
• Plastic liners and bags used where static can build
• Solvent use near dusty processes that nobody evaluated as a hybrid mixture
• Overhead dust on beams and loaders

Getting started

Have your layout, material list with Safety Data Sheets, conveying and collector details, and any dust test results ready. Most plastics plants can be studied remotely. For pricing, see what a DHA costs in 2026.

Keep reading

• NFPA 654 Is Now NFPA 660
• Dust Hazard Analysis (DHA) for Pharmaceutical and Supplement Powders
• Dust Hazard Analysis (DHA) for Paper, Tissue, and Corrugated Plants
• Combustible Dust Testing Explained: KSt, Pmax, MEC, and MIE

Questions from plastics facilities

Are plastic pellets a combustible dust hazard?

Pellets themselves are generally not, but the fines and streamers that break off during conveying are, and they collect in filters, receivers, and on surfaces.

Is regrind dust combustible?

Yes. Fine dust from granulators and regrind handling is combustible.

Why is grounding so important in plastics plants?

Moving plastic particles build static quickly, and a static spark can ignite a dust cloud. Grounding and bonding control that ignition source.

What is a hybrid mixture?

A combustible dust mixed with a flammable gas or vapor, like solvent vapor. It can ignite much more easily than the dust alone, even when the dust and the vapor are each below the level that would burn on their own, so a DHA looks for it.