Particle filters protect people, machines, and the environment from fine dust, soot, and solid contaminants. In the context of concrete demolition, special demolition, gutting works as well as rock excavation and tunnel construction, they appear in three central roles: as respiratory filters for personnel, as exhaust particle filters on combustion engines, and as fine filters in hydraulic oil. For work with tools from Darda GmbH—such as concrete demolition shears, rock and concrete splitters, combination shears, or hydraulic power packs—the correct filtration technology influences both occupational safety and the availability of the equipment.
Definition: What is meant by particle filters
A particle filter is a component or aid that mechanically retains solid particles from a gas or liquid stream. Depending on the application, fine dusts (e.g., quartz dust from concrete), diesel soot particles, or solid wear and dirt particles are separated from hydraulic fluid. The targeted spectrum ranges from visible dust down to respirable particles in the micrometer and sub-micrometer range. Decisive parameters include separation efficiency, filtration rating, permissible pressure drop, and resistance to the medium, temperature, and load.
Importance of particle filters in concrete demolition and special demolition
When crushing, pressing, splitting, and reducing the size of concrete and natural stone, dust containing crystalline silica can be generated. Tools such as concrete demolition shears and rock and concrete splitters operate with comparatively low vibration levels and often with less dust than percussive methods; nevertheless, fine particles are generated—especially during rework, removing coatings, or removing residual concrete. In parallel, diesel-powered carrier machines and power units produce exhaust particles. In addition, hydraulic tools require clean oil to operate valves, cylinders, and couplings reliably. Accordingly, respiratory filters, exhaust particle filters, and hydraulic oil fine filters are often integral building blocks of a safe and low-disruption workflow in these projects.
Types and operating principles
Respiratory filters for dusts
Respiratory filters are used in half or full-face masks to reduce fine dust and quartz dust. In dust-intensive work steps (e.g., breaking concrete ribs, exposing reinforcement, cutting with combination shears), particle-filtering classes with high separation efficiency are used. A proper fit test is essential, as is a filter insert with a protection class that matches the dust exposure. In combination with low-dust methods—such as controlled splitting or targeted size reduction with concrete demolition shears—exposure can be further reduced.
Exhaust particle filters (diesel soot filters)
Exhaust particle filters reduce soot and fine dust from combustion engines, for example on mobile power units or carrier machines. They typically use trapping filter media and are regenerated cyclically (passively via exhaust temperature or actively via targeted heat input). In enclosed or poorly ventilated areas such as tunnel headings, gutting works in existing buildings, or special operations with limited air exchange, an effective exhaust particle filter can be decisive for air quality. Alternatively, electrically powered hydraulic power units reduce particle and exhaust emissions at the source.
Hydraulic oil fine filters
In hydraulic systems, particle filters prevent the ingress and circulation of solid contaminants. Common configurations include suction and return-line filters, sometimes supplemented by pressure or off-line filters. The goal is an appropriate cleanliness class (e.g., per ISO 4406) to protect components such as cylinders of concrete demolition shears, stone-splitting cylinders, or valves in hydraulic power packs from wear. Key metrics include filtration rating (μm), separation efficiency (often described by the beta ratio), and permissible differential pressure.
Selection criteria for particle filters on the construction site
- Application and medium: breathing air, exhaust, or hydraulic oil—each medium requires specific filtration technologies.
- Particle spectrum: from coarse construction and drilling dust to respirable fine dusts or metallic wear particles in oil.
- Separation efficiency and filter class: the required protection determines the class; for hydraulic oil, the desired cleanliness class.
- Pressure drop and throughput: low pressure drop ensures performance and efficiency, especially for exhaust and hydraulic filters.
- Resistance: temperature, media, and vibration resistance depending on use (tunnel construction, deconstruction, cold/heat).
- Regeneration or replacement: technical concept (replaceable filter element vs. regenerable exhaust filter) and available infrastructure.
- Work environment: open construction site versus indoors/existing buildings; ventilation concept; proximity to sensitive areas.
Integration into tools and equipment from Darda GmbH
In practice, filtration technology interlocks at multiple points. When working with concrete demolition shears, combination shears, Multi Cutters, or steel shears, low-dust methods limit dust release at the component. Where dust is unavoidable, personal respiratory protection complements technical measures. Hydraulic power packs and long hydraulic hose lines benefit from clean oil: fine filters in the return line and careful fill and coupling hygiene maintain the functional reliability of rock and concrete splitters, stone-splitting cylinders, and concrete demolition shears. When engine-driven power units are used, exhaust particle filters reduce emissions—particularly indoors, in special demolition, and in tunnel construction.
Low-dust methods and supplementation through filtration technology
Controlled splitting of concrete often generates less fine dust than percussive methods. Nevertheless, a combination is sensible: wet the material, use local extraction, keep routes short, shield particle sources, and wear respiratory protection with suitable filter performance. This creates a multi-stage concept that sustainably lowers dust exposure.
Maintenance, replacement, and regeneration
- Respiratory filters: visual inspection before use; timely replacement in case of increased breathing resistance, moisture, or damage. Check mask fit regularly.
- Exhaust particle filters: observe regeneration strategy (active/passive), monitor differential pressure, check ash loading, and clean or service professionally as needed.
- Hydraulic oil fine filters: replace based on operating hours, differential pressure indication, or oil condition. Ensure cleanliness during topping up, and dispose of filter elements correctly.
Avoiding typical mistakes
- Unsuitable filter class: insufficient separation performance increases risk; overly dense media can create unnecessary pressure drop.
- Extended replacement intervals without monitoring: rising differential pressure reduces performance and can lead to bypass openings or leaks.
- Unclean installation: particle ingress during replacement undermines filtration, especially in hydraulic systems.
- Unsuitable use indoors: exhaust filters do not replace ventilation; supplementary ventilation and dust reduction measures remain necessary.
Use in tunnel construction, gutting works, and special operations
In tunnel construction and work in tight, poorly ventilated areas, exhaust particle filters and carefully selected respiratory protection determine air quality. Low-dust methods—such as splitting, targeted nibbling with concrete demolition shears, or controlled cutting with tank cutters in special operations—reduce emissions at the source. In gutting projects and deconstruction in existing buildings, a combination of particle filters, water mist, localized extraction, and thoughtful logistics (transport routes, partitions, cleaning routines) is advisable.
Occupational safety and environmental aspects
Safety-oriented selection and use of particle filters protect the health of employees and reduce environmental inputs. Requirements may vary by country, location, and activity. It is advisable to observe relevant rules and limits, use operational hazard analyses, and combine technical, organizational, and personal measures. Information on filter classes, separation efficiency, and operating limits should always be taken from the manufacturers’ documentation for the respective filters and approved for operational use.
Planning and documentation
A structured approach has proven itself for projects in concrete demolition and special demolition: analyze dust sources, define suitable particle filters and low-dust methods, establish replacement and cleaning intervals, and document differential pressures. In hydraulic systems, cleanliness classes, oil condition measurements, and service logs support the reliability of hydraulic power packs, concrete demolition shears, and rock and concrete splitters. Clear documentation facilitates audits, improves traceability, and contributes to safe, reproducible workflows.