When you’re cleaning industrial equipment, restoring brick, prepping a surface for coating, or stripping a piece of machinery down to bare metal, you’re typically choosing between dry ice blasting and sandblasting (or one of its abrasive cousins — soda, garnet, walnut shell). They’re both blast cleaning methods. They’re both delivered with compressed air. After that, the two are completely different tools.
Here’s how to choose.
The 30-second version
- Pick sandblasting when you want to remove material from the substrate — rust, scale, mill finish, old paint down to bare metal — and the substrate can tolerate abrasive erosion.
- Pick dry ice when you want to remove contaminant FROM the substrate without altering it — soot, grease, soft coatings, biological growth, residue — and you can’t afford water, abrasive, or secondary waste.
How they work
Sandblasting
A pressurized stream of abrasive media (silica sand, garnet, aluminum oxide, glass bead, plastic, walnut shell, soda) is accelerated by compressed air and impacts the surface. The media itself is the cleaning agent — it abrades, cuts and removes material by mechanical action. The contaminant and a portion of the substrate leave together.
Dry ice blasting
Rice-sized solid CO₂ pellets are accelerated by compressed air and impact the surface at high velocity. On impact, two things happen in sequence: the pellet flash-cools the contaminant (which contracts and lifts off the substrate), then sublimates from solid to gas. The gas expansion lifts the contaminant clear. The substrate itself is not mechanically eroded.
Side-by-side comparison
| Dimension | Dry ice blasting | Sandblasting |
|---|---|---|
| Abrasive on substrate | Non-abrasive | Abrasive |
| Secondary waste | None (CO₂ sublimates to gas) | Significant (spent media + contaminant) |
| Water | None | None (dry abrasive) or wet (dustless) |
| Conductive | Non-conductive | Some media conductive when wet |
| CFIA / FDA / USDA food-safe | Yes | No (residual media) |
| Heritage / delicate substrates | Excellent | Often damaging |
| Heavy rust / mill scale | Limited | Excellent |
| Soot, grease, soft coatings | Excellent | Overkill |
| Cost per hour | Higher | Lower |
| Downtime | Often zero (in-place) | Higher (cleanup, rinse) |
| Operator skill ceiling | High (technique matters) | Moderate |
| Containment required | Light | Heavy (dust, media recovery) |
When dry ice wins clearly
- Food and beverage equipment — no media residue allowed in the food zone
- Electrical and electronic equipment — non-conductive, no moisture
- EV battery and ESD-sensitive lines — no conductive dust
- Heritage brick, limestone, sandstone — substrate must not be altered
- Fire and smoke restoration — soot lifts; insurance wants no substrate change
- In-place industrial cleaning — equipment stays bolted together
- Marine hulls cleaned at the dock — no abrasive in the water
When sandblasting wins clearly
- Removing heavy rust, mill scale, or weld scale down to bare metal
- Profiling steel for primer or coating per NACE / SSPC specifications
- High-volume surface preparation where cost-per-square-foot is the driver
- Removing aggressive coatings (epoxy, urethane, lead paint) on tolerant substrates
- Shop work where containment is easy and media recovery is efficient
On cost
Honest answer: per hour, dry ice is more expensive than sandblasting. Sand-grade abrasive is cheap; dry ice pellets and the equipment to deliver them are not. But “per hour” is the wrong unit. The right unit is “per job, fully loaded” — and that includes:
- Containment and dust management
- Media disposal (especially for contaminated abrasive, which is regulated waste)
- Downtime and production lost to teardown / rinse / reassembly
- Damage to the substrate that needs repair afterward
- Loss of CFIA / FDA compliance during the cleaning window
When you add those up, dry ice is often cheaper end-to-end on jobs where downtime and substrate condition matter — food plants, electrical equipment, heritage masonry. Sandblasting wins clearly on bare-steel coating prep and any job where you’re using the abrasive to actually shape the surface.
A simple decision tree
- Do you need the substrate erosion? (e.g. profile for coating, remove rust to bare metal) → Sandblasting.
- Do you need to keep the substrate exactly as it is? → Dry ice.
- Is the equipment energized, food-zone, ESD-sensitive, or wet-intolerant? → Dry ice.
- Is the cost of downtime / cleanup / disposal high? → Often dry ice, even if hourly rate is higher.
- Is this a one-off bare-steel coating prep with no production impact? → Sandblasting.
What about soda blasting?
Soda blasting sits between the two — mildly abrasive, leaves a powdery residue, water-soluble. Better than sand on delicate substrates, but it’s still a media you have to clean up afterward, and it can leave behind sodium that interferes with subsequent coatings. We compare dry ice vs soda blasting in detail in a separate post.
Get a recommendation for your project
If you’re not sure which is the right tool for your job, we’ll tell you honestly — sometimes the answer is “sandblast it, this isn’t our job.” Call 226-627-4878 or email scott@ontariodryiceblasting.com and we’ll do a free site review.