Fine dust exposure describes the concentration of very small particles in the air that can be released during deconstruction of structures, during rock excavation, or during natural stone extraction. In practice, this particularly concerns activities such as crushing, splitting, cutting, size reduction, and material transport of mineral construction materials. For Darda GmbH, the key question is how to work with low emissions using suitable methods and tools—such as with concrete demolition shears or hydraulic rock and concrete splitters—to protect people and the environment while achieving precise, controlled results in concrete demolition and special demolition.
Definition: What is meant by fine dust exposure
Fine dust refers to particles with an aerodynamic diameter of less than 10 micrometers (PM10); the particularly relevant fraction is PM2.5. In work areas of deconstruction, a distinction between inhalable dust (E-dust) and respirable dust (A-dust) is also common. Mineral fine dust can contain quartz (crystalline silica); this is often the case when processing concrete, mortar, natural stone, or rock strata. Fine dust exposure describes the amount of these particles in the air that can potentially reach workers, residents, or the surroundings. It is influenced by material properties, the method used, tool geometry, energy input, moisture content, and airflow.
Causes and sources on construction sites and in deconstruction
In practice, fine dust arises through mechanical machining, abrasion, and fragmentation. Dust-intensive activities include dry cutting with high-speed cutting discs, grinding of concrete surfaces, drilling without dust extraction, striking and hammering on brittle building materials, as well as moving, rehandling, and sweeping. In contrast, methods that do not rely on high cutting speeds can markedly reduce dust release. Hydraulic splitting of concrete or rock and powerful pressing and crushing with concrete demolition shears work with controlled forces instead of sparks and abrasion—this reduces fine dust generation in many applications compared with purely rotating or abrasive methods.
Understanding and assessing emissions: particles, material, and process
The type and quantity of particles released depend on the structure of the material (concrete mix, aggregate, compaction), moisture content, reinforcement, tool engagement (cutting vs. splitting vs. pressing), and process control. When crushing with concrete demolition shears, mainly coarser fragments and chips are produced; the ultra-fine fraction is often lower by process compared with dry cutting. Hydraulic splitters create cracks by building up stress in the material and operate without high-frequency friction—this generally has a favorable effect on fine dust emissions. Where abrasive processes are unavoidable, wet operation, local dust extraction, and a moderate cutting speed reduce dust generation.
Practical dust mitigation: method, technology, organization
Effective dust management is based on the interaction of method selection, technical mitigation, organization, and personal protective equipment. Especially in interior spaces and sensitive environments, low-emission methods and closed process chains are crucial.
- Method substitution: Where possible, hydraulic splitting or crushing with concrete demolition shears instead of dry cutting or dry removal.
- Wet methods: Water mist or targeted wetting at the point of origin; meter water so that slurry is captured in a controlled manner.
- Dust extraction: Local capture near the source, flow-optimized collection, adequately sized filters (e.g., for fine dust).
- Enclosure/segregation: Dust-tight partitions, negative pressure in work areas, airlocks for material removal.
- Process control: Lower cutting speeds, sharp tools, suitable cutting sequences; controlled load cycles when pressing/splitting.
- Cleaning: Wet wiping or industrial vacuum cleaners with a fine dust filter; no dry sweeping.
- PPE: Respiratory protection with appropriate filter performance as well as eye and hand protection, supplemented by training on correct use.
Health effects and exposure pathways
Fine particles penetrate deep into the respiratory tract. Short-term effects can include irritation of the eyes, nose, and throat; long-term exposure to respirable dust and quartz-containing fine dust is particularly critical for health. The specific risk depends on concentration, duration, particle size, and mineralogy. Prevention starts at the source, supplemented by technical and organizational measures as well as suitable PPE. Statements on limits and legal requirements are always to be understood in general terms and do not replace an individual assessment of the specific case.
Application areas: low-dust work in deconstruction and extraction
Concrete demolition and special demolition
In selective demolition, mechanical crushing with concrete demolition shears enables controlled separation of concrete and reinforcement with comparatively low abrasion. Pre-wetting of separation lines, coordinated load cycles, and an orderly sequence (weakening, detaching, crushing) reduce fine dust formation. Where openings are created, hydraulic splitting can replace dry cutting in concrete demolition and deconstruction.
Gutting works and cutting
In buildings with sensitive use, emissions must be strictly limited. Wet-guided cuts, local dust extraction, and mobile negative-pressure units reduce spread. When load-bearing elements are removed, hydraulic splitters are an option to create openings without high-speed rotating equipment and to reduce dust load.
Rock excavation and tunnel construction
In rock, the combination of splitting and controlled crushing can reduce the need for abrasive methods. In tunnels, airflow management, wetting, tunnel ventilation, and dust extraction are especially important; using low-dust methods helps meet target values in enclosed spaces.
Natural stone extraction
When releasing blocks from the formation, hydraulic splitting often generates fewer fine particles than abrasive cutting methods. Decisive factors are cut layer planning, material moisture, and minimizing idle strokes to avoid unnecessary abrasion.
Special deployment
In areas with strict immissions requirements—such as near hospitals, laboratories, or ongoing production—low-dust methods are a priority. Enclosed work zones, time-coordinated workflows, and material-appropriate methods (splitting, pressing, shearing) contribute to emission minimization.
Tool selection in the context of fine dust mitigation
Tool selection fundamentally influences particle formation. Concrete demolition shears separate and crush by compression and shearing; this reduces high-energy spark and abrasion zones. Rock wedge splitters and hydraulic splitters transmit forces into boreholes or joints to initiate cracks—an emission-low alternative to dry cutting. Combination shears and Multi Cutters are useful where different materials must be separated without constantly switching to abrasive tools. Steel shears and tank cutters typically generate fewer mineral dusts but still require measures to control particles that can arise when processing coatings or residual adherences.
Hydraulic power packs and process control
Hydraulic power packs provide the necessary energy for splitters, shears, and crushers. For dust development, the process control is more decisive than the power pack itself: consistent oil supply, sensitive regulation, and appropriate stroke and cutting speeds prevent unnecessary abrasion. Electrically powered hydraulic power units also avoid local combustion emissions indoors; selection should be based on the requirements of the specific work environment.
Material properties that influence fine dust
Concrete strength, aggregate hardness, particle shape, aging, moisture content, and reinforcement ratio determine how a component breaks or chips. A high quartz content in aggregates favors the formation of fine particles; dry concrete generates more dust than moistened material. A material-appropriate strategy—targeted weakening, splitting along natural weaknesses, adapting tool geometry—reduces fine dust release.
Metrics, target values, and practical assessment
To assess fine dust exposure on construction sites, instantaneous and mean values of particle concentration are often used. In addition to PM10 and PM2.5, A-dust, E-dust, and, where applicable, quartz-containing fine dust are relevant in work areas. Limit and guideline values and occupational safety rules vary and must always be checked in the specific project context; they form the framework for risk assessments and the selection of protective measures.
Planning, documentation, and monitoring
A systematic approach combines the choice of low-emission methods with ongoing monitoring and clear documentation. This ensures transparency toward clients and authorities and improves process reliability.
- Analysis: Record material, surroundings, occupancies, emission pathways, and sensitive areas.
- Method selection: Where possible, splitting and crushing instead of dry cutting; plan wet operation and dust extraction.
- Technology and logistics: Source capture, water and slurry management, low-dust transport logistics.
- Monitoring: Indicative measurements at sources and immission points; adjust parameters if necessary.
- Training: Instruction on low-dust working methods, PPE, and cleaning.
Environmental and neighborhood protection
Immission control requires limiting dust outside the work zone. This includes scheduling, shielding, moistened traffic routes, cleaned exits, and careful material handling. Low-dust methods—especially hydraulic splitting and crushing with concrete demolition shears—support compliance with target values at the property boundary.
Safety and personal protective equipment
Even with consistent dust mitigation, PPE remains a component of the protection concept. Suitable respiratory protection, safety glasses, and hand protection must be matched to the method. Training, equipment maintenance, and clear task allocation ensure effectiveness. Legal aspects are always to be understood generally; project-specific requirements must be reviewed separately.