Already for a long time the particular agglomeration tendency of airborne Sillitin particles has been well known. The result is a considerable decrease of «free» particles < 5 µm which means very low concentrations of A fine dust which would not be expected from the classical ’water-dispersed’ grain size distributions. A fundamental possibility to quantitatively judge this «dusting behaviour» phenomenon is offered by the standard DIN EN 15051-3 ‘Workplace exposure – Measurement of the dustiness of bulk materials’. Based on this measuring concept, extensive studies have been run on the entire Neuburg Siliceous Earth product range.
The results confirmed the assumption of very small fractions of A dust in an impressive manner:
Relative to the silica portion, all test results were found in the range of 0.001 to 0.06 weight percent. This means that our products, following the standard, rank in the categories «low in dust» to «slightly dusting», and come out lower than the general bottom limit by more than one order of magnitude for the concentration of components specifically classified as directly organotoxic substances.
In conclusion, a labeling of the products of our portfolio according to the GHS directives is not required.
No great efforts are required from users to comply with the limiting dust levels when handling and working with our products.
The concentration of respirable dust in the breathing air at the workplace should not exceed the MEL value. This condition can be reached in various ways. The use of a suitable delivery mode helps from the beginning.
- Bulk Shipments and Big Bags
The most secure ways are bulk trucks or big bags. There are no delivery problems with these as they are sealed upon filling.
- Plastic Bags
These are also problem free provided that customers can add total bags to production batches - that means for a polyethylene bag a mixing temperature over 120 °C and for EVA bags over 95 °C.
- Normal Paper Bags
What about the normal paper bags? Here it is important that at any transfer point, e.g. filling or weighing stations, mixer and disposal points, effective dust extraction equipment is used which is installed according to the current technical knowledge and plant requirements.
Cleanliness at the workplace and a well functioning dust extraction unit are essential for a good clean working environment with regard to dust and chemicals. For good working practices with our products it is not necessary to take special measures or have special installations.
Particular attention should be paid to the works clothing for the production and maintenance personnel. Dirty work clothes should not be shaken but cleaned with a vacuum cleaner. Work clothes should also be separated from outdoor clothes.
For short term work without dust extraction especially for maintenance personnel fine masks of the class FFP2S (EN 149*) or masks with particle filters of the class PS2 (EN 140* and EN 143*) are to be used. A suppliers list can be requested from HOFFMANN MINERAL.
For the cleaning of the workplace, machines and equipment, an industrial vacuum cleaner must be used. The industrial vacuum cleaner which is used must comply with the relative security requirements and be fitted with a filter of < 1%.
The disposal of empty bags should take place in a dust extraction unit. This applies also for packaging the empty Big Bags together. A further possibility for the cleaner disposal of Big Bags would be to empty them with the help of an industrial vacuum cleaner. This will enable the empty bags to be pressed together virtually dust free.
* European Norm
Monitoring and Service features
We produce yearly more than 55,000 tonnes. The exposure of respirable dust is regularly monitored at Hoffmann Mineral. With the use of commercially available dust extraction equipment we ensure that the exposure in our production is well below the Maximum Exposure Limit (MEL) value. This experience we are pleased to pass on to our customers as part of our service.
Technical Advice for:
- The design of a safe working environment
- Optimization of existing installations
- Testing of your production unit. Free dust measurements in your production unit (*). You will then know if exposure is below the MEL value. If not, you can establish what must be done to improve the situation.
Further Services we offer are:
- Optimization of delivery mode: Our delivery service is quick and flexible. We are pleased to help you to find the optimum delivery mode. Speak with us for information!
- Information: If you have any further questions then our specialized staff is pleased to help you as the safe working conditions with our products are our common objective.
(*) Applies only to Germany and neighbouring countries. For other areas we are prepared to help you in finding for suitable testing institutes. Please speak with us.