Sandblasting Industry Insights

The Silica Dust Hazard

Crystalline silica is one of the most common minerals on Earth, found in sand, stone, concrete, and brick. When these materials are cut, ground, or blasted, they release respirable crystalline silica—microscopic particles that can penetrate deep into lung tissue.

Long-term exposure to silica dust causes silicosis, an incurable and often fatal lung disease. It also increases the risk of lung cancer, COPD, and kidney disease. According to OSHA, more than 2 million workers are exposed to respirable crystalline silica in their workplaces, with construction and sandblasting operations being among the highest-risk industries.

OSHA's Updated Regulations

In 2016, OSHA issued updated regulations (29 CFR 1926.1153) specifically addressing respirable crystalline silica exposure in construction and general industry. These rules, which are now fully enforced, drastically reduced the permissible exposure limit (PEL) for silica dust from 250 μg/m³ to just 50 μg/m³ as an 8-hour time-weighted average.

This means employers must implement engineering controls and work practices to keep worker exposure below this threshold. Traditional dry sandblasting, which creates massive silica dust clouds, makes compliance nearly impossible without expensive containment systems.

Why Dustless Blasting is the Solution

OSHA's regulations specifically recommend wet methods (also called "wet cutting" or "wet blasting") as a preferred engineering control for silica dust. Dustless blasting systems combine water with abrasive media, suppressing up to 92% of airborne dust at the source.

This approach is listed in OSHA's Table 1 as an approved method for controlling silica exposure during abrasive blasting operations. By using wet blasting, contractors can often eliminate the need for expensive air monitoring, medical surveillance, and respiratory protection programs required for dry blasting.

Compliance Benefits for Your Business

• Reduced Liability: OSHA violations for silica exposure carry penalties up to $15,625 per violation, with willful violations reaching $156,259. Dustless blasting helps avoid these costly fines.
• Worker Protection: Protecting your crews from silica exposure reduces health risks, workers' compensation claims, and potential lawsuits.
• Simplified Compliance: Following Table 1 methods like wet blasting means less paperwork, fewer medical exams, and streamlined compliance procedures.
• Competitive Advantage: Many industrial clients now require OSHA-compliant methods. Offering dustless blasting positions your company as a safety-focused, modern contractor.

Midwest Sandblasting's Approach

At Midwest Sandblasting, we've invested heavily in state-of-the-art dustless blasting equipment and trained our crews specifically in OSHA-compliant wet blasting techniques. Every project we undertake prioritizes worker safety and regulatory compliance, giving our clients peace of mind that their contractors are following best practices.

Whether you're a facility manager concerned about contractor compliance or a restoration company looking for a safe subcontractor, our commitment to OSHA standards sets us apart in the Chicago sandblasting market.

Selecting the right blasting media is crucial for achieving optimal results without damaging your substrate. Each abrasive material has unique properties—hardness, particle size, shape, and density—that determine its effectiveness for specific applications.

Understanding Media Characteristics

Hardness: Measured on the Mohs scale, harder media cuts more aggressively but can damage soft surfaces. Steel grit (Mohs 7-8) is much harder than walnut shells (Mohs 3-4).

Particle Shape: Angular particles (like crushed glass or garnet) cut aggressively and create surface profile for coating adhesion. Round particles (like glass beads or steel shot) polish and peen surfaces without creating deep anchor patterns.

Density: Denser media like steel shot delivers more kinetic energy, cutting faster but potentially causing more substrate damage on delicate surfaces.

Media Selection by Surface Type

Steel & Heavy Metals

For structural steel, bridges, and heavy equipment, use aggressive media like garnet, steel grit, or aluminum oxide. These materials remove heavy mill scale, thick rust, and old coatings while creating the deep anchor pattern (3-5 mils) needed for industrial coatings like epoxies and urethanes.

Concrete & Masonry

Silica sand or crushed glass works well for concrete profiling and coating removal. For decorative concrete or when dust control is critical, use wet blasting with recycled glass. For gentle cleaning of historical brick, switch to soda blasting to avoid mortar damage.

Wood Surfaces

Wood requires the gentlest media to avoid splintering and fiber damage. Walnut shells, corn cob, or low-pressure soda remove paint and stains while preserving wood grain. These are ideal for log homes, decks, and antique furniture restoration.

Aluminum & Soft Metals

Glass beads or plastic media clean aluminum, brass, and copper without dimensional changes. These are common in aerospace and automotive applications where maintaining tight tolerances is critical.

Special Application Media

Soda Blasting (Sodium Bicarbonate): The go-to choice for graffiti removal, fire damage restoration, and mold remediation. Soda is water-soluble, non-toxic, and has natural deodorizing and rust-inhibiting properties. Used by the City of Chicago's graffiti removal program.

Dry Ice Blasting: Frozen CO₂ pellets sublime (turn to gas) on impact, leaving no secondary waste. Perfect for food processing equipment, mold cleaning, and applications where media residue is unacceptable.

Cost vs. Performance Considerations

While silica sand is the cheapest media (around $5-10 per bag), health and safety regulations increasingly favor alternatives. Recycled glass costs slightly more but offers comparable performance with better environmental and safety profiles. Premium media like garnet or aluminum oxide cost 2-3x more but cut faster, reducing labor costs and often proving more economical on large projects.

The Challenge

A major manufacturing company in the Chicago suburbs needed to refurbish a 50,000 square foot warehouse floor and prep interior structural steel for recoating. The facility had been in continuous operation for 30 years, with the concrete floor covered in layers of oil stains, tire marks, and deteriorated epoxy coatings. Support beams showed significant rust and peeling paint.

The catch? The warehouse needed to remain partially operational during the work, limiting us to night shifts and weekends. The client also had strict environmental requirements—no hazardous dust clouds that could contaminate their manufacturing processes or require extensive facility-wide cleanup.

Our Solution

Midwest Sandblasting deployed two mobile dustless blasting units and a six-person crew working 10-hour night shifts. We divided the project into phases:

Phase 1: Concrete Floor Profiling (Days 1-6)

• Used recycled crushed glass media with our dustless system to strip old epoxy and create a consistent 2-3 mil anchor pattern for the new coating
• Worked in 10,000 sq ft sections, allowing the client to continue operations in unaffected areas
• Dust suppression kept airborne particles below OSHA limits, eliminating the need for facility-wide air quality monitoring
• Completed 8,500-9,000 sq ft per night shift

Phase 2: Structural Steel Preparation (Days 7-10)

• Switched to garnet media for aggressive rust and paint removal on steel beams and columns
• Achieved SSPC-SP 10 (near-white metal) cleanliness standard required for the industrial coating specification
• Wet blasting prevented heat buildup that can warp thin structural elements
• Mobile lifts allowed us to work on beams up to 25 feet high

Project Results

Timeline: Completed in 10 working days (two weeks of night shifts), meeting the client's aggressive schedule and allowing the painting contractor to begin work immediately.

Quality: Third-party inspection confirmed we achieved the specified surface profile and cleanliness standards across 100% of the project area. The new epoxy floor coating, applied by the client's contractor, showed excellent adhesion.

Safety & Compliance: Zero safety incidents. Air quality monitoring showed we maintained OSHA-compliant dust levels throughout the project. No disruption to ongoing manufacturing operations in adjacent areas.

Client Satisfaction: The manufacturing company was so impressed they've now contracted us for a similar project at their Indiana facility, demonstrating the value of quality work and reliability.

Key Takeaways

• Dustless technology made the impossible possible: Traditional dry blasting would have required complete facility shutdown and extensive post-blast cleanup. Wet blasting allowed us to work while manufacturing continued.
• Mobile equipment saves time and money: No need to transport materials or shut down the facility. We brought the shop to them.
• Proper media selection matters: Using different media for concrete vs. steel optimized both speed and quality.
• Phased approach minimizes disruption: Strategic scheduling and section-by-section work kept the client operational.