Fire & explosion protection for extraction systems and filtration equipment
for safety in your production operation
Around 80% of all explosion protection measures must be organisationally regulated in one company. A residual risk remains.
There are approx. 12,000 flammable gases and approx. 5,000 flammable substances in various combinations. In the following, we would like to point out and explain the most important points for the safety of your extraction and filtration systems.
The Background
In many factories, flammable substances such as gases, vapours, mists or dusts are produced or escape during production, processing, transport and storage. In combination with the oxygen in the air, an explosive atmosphere can arise. A small spark could cause a fire or an explosion.
According to the German Statutory Accident Insurance (DGUV), the number of fatal accidents at work in the first half of 2017 increased in contrast to the trend. In about 3,500 accidents at work subject to notification, the cause is a fire or an explosion. The risk of fire and explosion is part of the hazard factors that must be considered in every risk assessment (compulsory according to the German Industrial Safety Ordinance!). Secondary fires cannot be ruled out after a plant explosion. This can quickly impact the survival of an entire company!
In order to achieve optimal explosion protection, technical solutions as well as compliance with the types of protection, zone classification and standards are necessary. This is based on legal provisions, such as the ATEX Directive 2014/34/EU of the European Union. For the extraction of fire-endangered types of dust as well as gases and vapours, an investment in filter systems with constructive explosion and fire protection measures from the point of view of occupational and production safety is necessary.
Solutions for fire and explosion protection of your extraction and filtration systems
Schuko extraction and filtration systems are manufactured according to the valid regulations for fire and explosion protection. In every plant system design, we pay close attention to the zone classification to ensure a safe design of the necessary components.
Dust and chips made of wood, plastic, paper, mixed materials such as CFRP and GFRP as well as metal are above all one thing: Explosive! Therefore, extraction and filtration systems must be designed and built to be fundamentally safe.
The risk of fire or explosion can be minimized with the following measures. The danger posed by extraction systems with low crude gas volumes is very manageable, so that in most cases special protective measures can be dispensed with. Especially for mobile dust extractors, which can be placed in the interior of the workshop, as well as for large industrial filtration systems, the following possibilities apply.
Measures of our mobile dust extractor for indoor installation
- Pressure shock-resistant design according to EN 16770
- H3 and GS certification by the DGUV (Concerns wood dust and chips! Depending on power size and equipment!)
- Fire extinguishers (only necessary for a specific unit size):
Powder extinguisher or ignition protection system - Discharge through tested ATEX rotary valve when disposing via briquetting press, BigBag or container
Measures for our stationary filtration equipment
- Use of spark extinguishing systems, which are to be planned especially when spark-generating machines are extracted, or when machines are extracted, where there is an increased risk of sparks being generated, e.g. through impact and friction sparks in hackers or multi-blade rip sawing machines as well as when cutting multiplex boards on saws.
- Fire protection collar in F90 wall and smoke detector insert, which switch off the filtration system in the event of fire within the workshop via a signal to the control.
- Explosion decoupling by means of pipe check valves before the filter inlet in order not to guide the explosion pressure of the filtration system through the crude gas line.
- Smoke detector insert in the return air duct, which switches off the filtration system in the event of a fire within the filter system via a signal to the control.
- Explosion dampers in the filter housing ensure direct and safe pressure relief. Moreover, mounted safety position limit switches ensure the direct shutdown of the system in the event of an explosion.
- 2 x 90° deflection with double pressure relief surfaces in the return air ducts in order to relieve the explosion pressure in the direction of return air ducts (explosion decoupling).
- Fire protection/fire damper in the return air duct through the F90 wall, which automatically closes the duct in case of fire (fire protection decoupling).
- Dry fire extinguisher, through which the fire hose of the fire department can be easily connected in case of fire in order to trigger a pre-installed sprinkler system.
- In addition to explosion decoupling, ATEX-approved explosion-proof rotary valves are also used for material discharge.
Measures for paint mist extraction solutions
The paint shops used for the extraction of solvent-based paints are subject to special requirements due to their explosive properties. Planning fundamentals such as room geometry, lighting and air volumes are particularly crucial here.
For fire and explosion protection in paint shops, the following points should be noted:
- ATEX zoning
- Classification of fire-prone areas
- Air exchange rate
- Concentration assessment
- Type and amount of coating materials used
- Coating process
- Flash point and ignition temperature
- Explosion protection document
- xplosion protection document
Furthermore, the following components can contribute to the protection against fires and explosions:
- Use of fire dampers
- Use of flame-retardant cardboard filters, self-extinguishing according to DIN 4102-1
- Use of zone-appropriate equipment, e.g.
- explosion protected fans,
- paint shop suitable explosion protected lighting (at least 750 lux),
- static-dissipating floors (flooring must not be flammable and must be easy to clean)
Selected tests that our various extraction and filtration equipment have passed:
- DGUV test of our mobile dust extractor Vacomat, H3 and GS (depending on the size) approval by the German Statutory Accident Insurance (DGUV)
- Fire resistance test of the filter housings EcoVar Validus and N-1000 by the MPA Dresden GmbH, recognised testing, monitoring and certification body for building supervision
- Testing of the filter pressure resistance of the Validus series by the FSA Research Institute for Applied Systems Safety and Occupational Medicine, Mannheim
- EC Type Examination Certificate of the Schuko ATEX rotary valves: according to ATEX Manufacturer Guideline 2014/34/EU (Główny Instytut Górnictwa, 40-166 Katowice, Plac Gwarków 1, Poland, www.gig.eu)
- EC Type Examination Certificate of Schuko ATEX Check Valves: according to Directive 94/9/EC (today EU standard EN 16447:2014) (Główny Instytut Górnictwa, 40-166 Katowice, Plac Gwarków 1, Poland, www.gig.eu)
Databases for dealing with explosive dusts and gases
The dangers of deposited dusts are underestimated! The swirling of a dust layer with a thickness of more than 1 mm can quickly create an explosive dust atmosphere. Ensure cleanliness in your company!
At this point we would like to draw your attention to the free Hazardous Substance Information System of BG RCI. At www.GisChem.de you will find all the necessary information regarding the explosion protection of your substance.
You can find additional information about handling explosive dusts and gases
- in the Hazardous Substances Ordinance (GefStoffV),
- in the various Safety Data Sheets (SDS),
- in the Gestis Dust Ex IFA database: www.staubex.ifa.dguv.de,
- in the substance information system of federal and state governmentGSBLpublic www.gsbl.de,
- and under Chemsafe Database www.chemsafe.ptb.de (registration required!), which originated from the joint project of PTB (Physikalisch-Technische Bundesanstalt) and BAM (Federal Institute for Materials Research -and Testing).
(Source: www.bgrci.de/exinfode/ex-schutz-wissen/brenn-und-explosionskenngroessen)
Overview of selected laws, standards and information:
- Directive 2014/34/EU (formerly Directive 94/9/EC) for equipment and protective systems intended for use in potentially explosive atmospheres, also known as ATEX 95 (formerly ATEX 100a)
- Directive 1999/92/EC on the safety of workers working in potentially explosive atmospheres, also known as ATEX 137 (formerly ATEX 118a)
- Operational Safety Ordinance BetrSichV according to Directive 2009/104/EC, for the provision of work equipment by the employer and the use of work equipment by the employees (explosion protection: Annex 2, Section 3)
- Explosion protection regulations (EX-RL) DGUV Rule 113-001
- Machinery Directive 2006/42/EC
- EU standard EN 16770 for extraction of wood dust and chips for indoor installation
- EU standard EN 12779 for fixed extraction systems for wood dust and chips
- EU standard EN 16447: 2014 for check valves for explosion decoupling
- DGUV Information 209-045 (formerly BGI 739-2) for extraction systems and silos for wood dust and –chips
- DGUV Information 209-044 (formerly BGI 739-1) for wood dust health protection
- VDI 2263 Dust fires and dust explosions – hazards, assessment, protective measures, the VDI Society for Energy and Environment
- DGUV Information 209-046 (formerly BGI 740) for painting rooms and equipment for liquid coating materials
- DIN EN 12215: Coating plants - Spray cabins for liquid organic coating materials - Safety requirements
- DIN EN 13355: Coating plants - Combined spray and drying cabin – Safety requirements
- GefStoffV - Hazardous Substances Ordinance
- Further…
(For information: EU or EC directives are European, IEC standards are international, EN standards are European, DIN EN standards are German)