Explosion prevention and explosion protection according to ATEX

Information on the design of air pollution control systems


It is necessary to consider all physical circumstances and legal regulations when designing an air pollution control system and air purification.

Keller provides extensive knowledge based on research and practical experience.

Determining the explosion parameters in the design of dust collection systems

As a result of EU guideline ATEX 137, system operators of machines at risk of explosion are required to determine and evaluate the risk of explosion by filing an explosion protection document.

To fulfill this requirement it is frequently necessary to determine explosive dust parameters, among other issues, for the suitable design of dust collection systems.

Dust analysis by Keller sets matters straight


Keller is capable of providing the necessary support for the evaluation of the explosion hazard, the detection of the explosive parameters and establishing explosion protection measures with two interrelated service packages.

< Additional information on the left

Package 1 (explanation)
To determine if explosion protection measures are necessary


Scope of the examination:
– Sieving on dust particle size < 63 µm
– Determining explosiveness with

the modified Hartmann device
– Not explosive
– Explosive
– Dust explosion class St1
– Dust explosion class St2

– Total disposal volume
– Volume of dust particles: approx. 100 g

Price: EUR 665.00
plus VAT

Package 2 (decision)
To determine if the prevention of ignition is sufficient, or if explosion protection is necessary:


Provided that ignition sources are not created during the extraction process, the prevention of ignition sources as an explosion protection is sufficient (according to regulations for explosion protection for dust with a MIE of > 10 mJ). There are no explosion protection measure requirements for pressure relief, for example, or for explosion suppression.

Scope of the examination:
– Sieving on dust particle size < 63 µm
– Definition of particle size distribution
– Determination of the minimum ignition
energy without electrical source
– Total disposal volume
– Volume of dust particles: approx. 300 g

Price: EUR 1,951.00
plus VAT

Information for evaluation:


The sample should be representative of the process being evaluated.

Please send the sample in a securely closed envelope to the following address:

Keller Lufttechnik GmbH + Co. KG
Mr. Jens Kuhn
Neue Weilheimer Str. 30
73230 Kirchheim unter Teck
Germany
Important:
The following information must be provided with the dust sampleDetails

– Company, contact person with
e-mail address
– Name of the product (type of dust)
– Storable at room temperature?
– Hygroscopic?
– Skin irritant?
– Contains solvents?
– Is it a hazardous substance?
– Are there any regulations concerning
the handling of the substance?

The duration of the evaluation
is normally 10 working days.
Test report is sent to contact
person by e-mail.

Print form >

Package 3
To design explosion protection measures such as pressure relief or explosion suppression.


Pressure relief or explosion suppression. Operational parameters are of vital importance.

Scope of examination:
– Sieving on dust particle size < 63 µm
– Definition of particle size distribution
– Determining the pressure increase

(KSt value) and of the max. explosion pressure pmax in the 20 L ball (screening means that only one test is made)

– Total disposal volume
– Quantity of dust particles: approx. 200 g

Price: EUR 2,460.00 plus VAT

Package 4
Determining the mixture ratio for inertisation with limestone powder.

Inert limestone powder is added to prevent an explosive environment. Additional explosion protection measures in the separator are not necessary.

For optimal results when supplying limestone, the suitable dust – limestone powder combination ratio must be determined. The ratio can be reduced to 1:1.

Scope of the testing:
– Sieving on dust particle size < 63 µm
– Definition of the particle size distribution
– Determining the necessary

mixing ratio of the limestone powder: explosive dust in the 20 L ball in 12 % increments

– Total disposal volume
– Quantity of dust particles: approx. 500 g

Price: EUR 3,883.00 plus VAT

Information for evaluation:



The sample should be representative of the process being evaluated.

Please send the sample in a securely closed envelope to the following address:

Keller Lufttechnik GmbH + Co. KG
Mr. Jens Kuhn
Neue Weilheimer Str. 30
73230 Kirchheim unter Teck
Germany
Important:
The following information must be provided with the dust sampleDetails

– Company, contact person with
e-mail address
– Name of the product (type of dust)
– Storable at room temperature?
– Hygroscopic?
– Skin irritant?
– Contains solvents?
– Is it a hazardous substance?
– Are there any regulations concerning
the handling of the substance?

The duration of the evaluation
is normally 10 working days.
Test report is sent to contact
person by e-mail.

Print form >

The clarification of these ques-
tions is the operator’s respon-
sibility (ATEX guidelines)

Decision supports:
– Specificaton by operator/
safety data sheet
– Evaluation with GESTIS
dust-ex-data base
– Dust examination by
Keller/test institute

RELOAD
YES
Info >
Examples: organic dust,
light metal dust, steel dust
NO
Info >
Examples: mineral dust,
ceramic dust, normally
stainless steel, welding fume
No further measures
necessary
Can an explosive environment
be avoided?

< back
NO
Info >
Avoidance of ignition sources
within the extraction system
with dry separation
PARTIAL
Info >
Cleaning during downtime

Monitoring concerning
entry of ignition sources

Special case:
ProSens protection concept
with MQL
YES
Info >
During exhaust air oper-
ation through wet sepa-
ration
Only small amount of dust
by solid inertisation
By wet separation
or solid inertisation
  • ProSens protection concept
    • For processes with a small amount of dust and rare ignition sources
    • Cleaning during downtime
    • Monitoring concerning entry of ignition sources

    MIE > 10 mJ (normal ignition
    energy) – and can the collection
    of effective ignition sources be
    excluded?

    < back
    NO
    YES
    No further measures
    necessary
    Outside installation?
    < back
    YES
    NO
    Horizontal pressure relief
    via burst panels
    (Safety area approx. 10 - 20 m)

    Vertical pressure relief
    (deflection via bursting channel)
    (Reduced safety area (approx. 2.5 - 3.5 m))

    Installation at an outside wall?
    < back
    YES
    NO
    Horizontal pressure relief
    via burst panels + safe keeping
    (Safety area approx. 10 - 20 m)

    Angular pressure relief
    via burst panels + Targo-Vent + safe-keeping
    (Reduced safety area (approx. 7 - 14 m))

    Is metal dust extracted?
    < back
    YES
    NO

    • Design on Pmax (Pressure shock resistance normally 10 bar)
    • ProSens protection concept

        - For processes with a small amount of dust and rare ignition sources
        - Cleaning during downtime
        - Monitoring concerning entry of ignition sources

    • ProPipe

        - Safety area
        - Flameless pressure relief for aluminum dust at KST = 300

    • ProPipePlus

        - No safety area
        - Flameless pressure relief for aluminum dust at KST = 180

    • ProVentPlus (with TR-1)

        - No safety area
        - Flameless pressure relief for aluminum dust at KST = 180

    • Flameless pressure relief ProVent

        - Safety area
        - Pressure shock resistance normally 0.4 bar

    • Explosion suppression

        - No safety area
        - Pressure shock resistance normally 0.4 bar
        - With toxic dusts, gases/hybrid mixtures