Dust Extraction for Construction, Rock & Tunnels

Dust extraction is a central topic in deconstruction, strip-out, natural stone extraction as well as rock and tunnel works. Wherever mineral materials such as concrete, masonry, or natural stone are separated, broken, split, or crushed, fine dust is generated. This can restrict visibility, burden equipment, and endanger health. Especially during drilling, milling, sawing, and grinding, but also when downsizing with concrete demolition shears or when pre-drilling for rock splitting cylinders, a well-thought-out dust management is required. Dust extraction complements the mechanical intervention — for example with rock and concrete splitters, combination shears, or multi cutters — with a technical airflow that captures particles early, transports them, and filters them safely.

Definition: What is meant by dust extraction

Dust extraction refers to the targeted capture of airborne particles directly at the point of origin (source extraction) or in the immediate work area (point extraction), their conveyance through conductive hose lines, and the filtration and separation in suitable equipment. The goal is to remove mineral fine dust and coarse particles from the air, minimize emissions into the work area, and enable safe disposal. Depending on the method, dry extraction systems with high-performance filters are used or — as a complementary measure — dust suppression by water mist is applied. Critical building blocks are the capture element (hood, nozzle), volume flow, negative pressure, filtration technology, and an airflow adjusted to the work process.

Dust sources in deconstruction and natural stone extraction

Mineral dust arises wherever solids are subjected to mechanical stress. Typical sources in the application areas of Darda GmbH are:

Drilling of anchor and splitting holes in concrete and rock (preparation for rock splitting cylinders and rock and concrete splitters): fine drill dust with a high proportion of quartz-bearing particles.
Cutting and crushing of concrete with concrete demolition shears, combination shears, and multi cutters: fracture dust at the break zone, mostly localized; additionally dust from detachment of the cement matrix and aggregates.
Cutting of tanks and steel components with tank cutters or steel shears: predominantly metal particles; lower dust quantities overall, but depending on coatings (e.g., old paint) to be assessed carefully.
Rock excavation and tunnel construction: During tunnel face advance, stabilization drilling, and excavation, mineral fines are produced that build up quickly in confined spaces.
Strip-out: Selective removal of building components generates mixed dust from plaster, screed, mortar, and concrete residues.

A key advantage of mechanical splitting methods with rock and concrete splitters: crack formation occurs without abrasive chip formation, which typically reduces dust generation compared to percussive or abrasive methods. Nevertheless, pre-drilling remains dust-relevant and requires effective extraction technology.

Operating principles of dust extraction: capture, conveyance, filtration

Effective dust extraction follows three steps:

Near-source capture: Hoods, nozzle elements, or enclosed work zones keep the distance to the source minimal. The closer the capture is to dust generation, the less volume flow is needed and the lower the secondary exposure.
Flow-safe conveyance: Smooth, antistatic hoses with suitable sizing reduce pressure losses. Short hose runs, few bends, and tight couplings ensure negative pressure.
Multi-stage filtration: Pre-separators, cyclones, or wet separators remove coarse fractions; fine filtration via cartridge filters and high-efficiency final stages captures respirable dust. Closed disposal systems minimize contact with the dust.

In practice, dry dust extraction and dust suppression with water complement each other. While water mist binds particles, extraction removes remaining fine dust from the air. The choice depends on the method, ambient conditions, and the requirements for visibility, cleanliness, and follow-on trades.

Dust extraction in combination with hydraulic tools

The hydraulic tools of Darda GmbH work gently on materials and precisely. The type of dust generation varies depending on the tool and intervention:

Concrete demolition shears: Local fracture dust occurs when downsizing concrete components. A spatially close point extraction in the shear work zone is recommended; in interior spaces, additionally an area extraction or negative pressure containment to remove fine dust.
Rock and concrete splitters and rock splitting cylinders: Splitting itself produces little dust, but the required pre-drilling produces much more. Here, on-tool dust extraction on the rotary hammer with a suitable hood is the most effective measure; a pre-separator for drill dust is helpful.
Combination shears and multi cutters: When separating mineral layers, minor fine dust can occur. A mobile point extractor in the immediate vicinity of the cutting line keeps the view clear.
Steel shears and tank cutters: Primarily metal chips/particles, usually lower dust loads. The process air should nevertheless be guided, particularly with coated or contaminated surfaces; extraction near the cut zone reduces particulate and odor-active emissions.
Hydraulic power packs: They drive tools and are part of workplace organization. Hose routing and setup areas should be planned so that extraction hoses are guided safely and tripping hazards are avoided.

Principle: Capture dust at the source. Where on-tool solutions are not possible, flexible capture hoods, adjustable slot suction tubes, or process-near capture tables help. In enclosed areas, negative pressure with filtered exhaust can reduce residual loads.

Application areas: requirement-appropriate extraction

Concrete demolition and special demolition

In heavy concrete demolition, different dust profiles arise depending on the method. Concrete demolition shears reduce secondary emissions through controlled downsizing; the largest dust quantities occur during preparatory cutting, drilling, or grinding. A proven practice is a combination of on-tool dust extraction, mobile point extraction in the work area, and air-side zoning that routes dust-laden air out of the deconstruction area.

Strip-out and cutting

With selective measures, visibility and cleanliness are particularly important to protect adjacent areas. Dust airlocks, negative pressure containment, and finely tuned point extractions at cutting and drilling points limit spread. Short runs to the filter unit and closed disposal systems facilitate operations in occupied or sensitive buildings.

Rock excavation and tunnel construction

In underground spaces and tunnels, fine dust accumulates rapidly. In addition to source extraction, an overarching airflow management with supply and exhaust air is crucial. Local capture at drill carriages, on-tool dust extraction during pre-drilling for rock splitting cylinders, and directed removal of process air improve visibility and reduce deposits on equipment and rails.

Natural stone extraction

When splitting natural stone, dust generation is comparatively low; the drilling process remains decisive. A robust drilling dust extraction, combined with pre-separation, protects operators and keeps raw blocks clean. For dry cutting or calibration work, capture should take place directly at the working edge.

Special applications

For work in sensitive environments — for example in technically equipped rooms or contaminated areas — additional measures are advisable: encapsulated work zones, directed airflow, redundant filter stages, and seamless maintenance documentation. Here the rule is: size conservatively and place capture points so that no undesirable turbulence is created.

Planning and sizing on the construction site

The effectiveness of dust extraction depends on planning. Key points:

Proximity to source: Position capture elements so that the inlet edge is at most a few centimeters from the dust source.
Volume flow and negative pressure: Size sufficiently so that the inlet velocity safely captures dust. Longer hoses and tight radii increase the requirement.
Hose management: Short, smooth, and conductive hoses; tight couplings prevent false air. Grounding reduces electrostatic charging.
Pre-separation: Cyclones or settling containers collect coarse fractions and relieve fine filters — particularly advantageous for drill dust.
Filter class: Fine filters with high separation efficiency; for fine mineral dusts, pay attention to final filters with very high efficiency.
Disposal: Empty dust containers with low dust; ideally with dust-tight bags and mechanical locking.

For construction sites with changing activities, a modular concept has proven itself: on-tool dust extraction for recurring processes such as drilling; mobile point extraction for variable activities such as shear or cutter work; optionally an air management of the room when several dust sources are active in parallel.

Filtration technology: pre-separators, cartridges, final filters

The filter chain determines the overall performance of dust extraction:

Coarse stage: Cyclone or settling separators remove drill dust and coarser fractions. Advantages: less filter load, more constant negative pressure.
Fine stage: Cartridge or flat-fold filters with automatic or manually triggered cleaning keep the volume flow stable. Regular cleaning with the suction flow switched off protects the filter medium.
High-efficiency stage: Final filters with very high separation performance for fine mineral fractions. Seals and frames are just as important as the medium itself; leaks reduce effectiveness.

In addition to dry filtration, a water stage can bind particles in special applications. Proper disposal of the slurries must be ensured. Filter replacement and inspections should be documented and carried out at fixed intervals.

Integration into workflow and ergonomics

Dust extraction should work effectively and at the same time unobtrusively. Practical aspects:

Quick couplings and robust hoods simplify tool changes, e.g., between different drill diameters for rock splitting cylinders.
Brackets and hose guides relieve operators and avoid kinks.
Acoustics: Position extraction units so that sound pressure at the workplace remains low without creating long hose runs.
Energy: Adapt the output of the extraction to the actual dust generation; unnecessarily high volume flows increase energy demand and can stir up particles.

With concrete demolition shears or combination shears, it is helpful to guide the suction nozzle along the component and move it with the work progress. During drilling, guide aids should ensure that the hood seats cleanly on the surface.

Occupational safety and technical rules

General rules of technology and industry-standard safety standards apply to the handling of mineral dusts. These include the selection of suitable extraction and filtration technology, regular maintenance, safe disposal, and, where appropriate, personal protective measures. Company risk assessments define which combination of source extraction, room air management, and organizational measures is appropriate. Information on limit values and standards should always be obtained up to date from publicly accessible, reliable sources. The above notes are of a general nature and do not replace a case-by-case assessment.

Practical guide: typical work scenarios

Pre-drilling for rock and concrete splitters

Define drilling scope and diameter; select a suitable extraction hood.
Connect on-tool dust extraction with a short hose run; place a pre-separator upstream for drill dust.
Check airflow: the hood must rest securely on the surface; minimize false air.
Empty drill dust containers regularly; clean filters without stirring up dust.

Concrete demolition shears in concrete demolition

Position point extraction at the fracture zone; move the nozzle with the shear stroke.
In interior spaces, additionally ensure a directed exhaust airflow out of the work area.
Track fracture edges to capture trickling fine fractions directly.
Low-dust disposal of filter residues; wet-clean the work area after completion.

Strip-out and cutting

Define the work zone and separate it on the air side; negative pressure containment if required.
Use on-tool dust extraction during separating/cutting; secure hose routing.
Monitor fine filters; if throughput drops, clean or replace filters.
Plan the construction power supply and power unit position so that the extraction unit can remain close to the source.

Typical error sources and how to avoid them

Excessive distance between dust source and nozzle: capture loses effectiveness. Solution: move hoods closer to the source, use brackets if necessary.
Leaky connections: false air reduces negative pressure. Solution: tight couplings, regular visual inspection.
Overloaded filters: decreasing volume flow. Solution: use pre-separators, maintain filters, and replace on schedule.
Unsuitable airflow: turbulence keeps dust aloft in the room. Solution: directed exhaust, prioritize source over room extraction.
Unclear responsibilities: lack of maintenance. Solution: define responsibilities, intervals, and checklists.

Sustainability and resource efficiency

Good dust extraction protects people, machines, and materials — and increases efficiency. Clean workplaces reduce cleaning effort, extend maintenance intervals of tools and hydraulic power packs, and prevent consequential damage from abrasive dust. An energy-smart approach uses demand-based operation with proper sizing, short runs, and well-maintained filters. Reusable pre-separators and low-dust disposal systems reduce material consumption.