Skip to main content

Rubber floor mats for animal houses

DLG-APPROVED: "Manufacturing process certification, PAH test"

Download Printable version

The approval

The DLG quality marks and seals stand for independent tests and certifications of products, systems and processes (such as manufacturing processes) that are based on requirements that are drawn from the field. The test criteria are laid down by independent test commissions that are made up by volunteer experts. These criteria describe the methods of testing the essential and value determining features of products or processes. The speci­fications that define a specific quality of a product or process are drawn from the field and are in line with the latest scientific findings. The quality mark is awarded to a product or process after the test has revealed that it complies with the high DLG standards. Depending on the type of test and product group, the mark is either awarded under the RAL quality assurance scheme or as DLG quality mark under the DLG quality standards scheme. The DLG tests provide consumers with valuable purchase information and at the same time ensure that the quality of the tested product is maintained at a consistently high level. By submitting their products to a DLG test, manufacturers agree to accept an ongoing and independent quality monitoring programme for the products, systems and processes tested. This programme is subsequently carried out by qualified samplers and auditors who on an ongoing basis take unannounced samples at the manufacturer’s or dealer’s premises for subsequent analysis or carry out audit processes.

This DLG quality mark test involved an assessment and evaluation of the quality assurance programme as implemented in the manufacturing process of floor mats for animal houses and also involved measuring PAH migration to Tenax in all rubber blends. The test was based on the ‘Project report on PAH migration from rubber floor mats’ as provided by Fraunhofer-Institut für Verfahrenstechnik und Verpackung IVV, Freising, Germany, dated 8 August 2018.

The manufacturing process was certified to the ISO 9001 : 2015 standard. This standard defines the introduction and enforcement of a quality management system within an organisation. It affects all organisational processes that have an impact on customer demands and legal requirements. The audit of the Tittmoning production site covered all processes that are relevant for achieving a consistently high quality of the product. It focused on the entire manufacturing chain – from procurement of the raw materials to the moment the finished product is prepared for delivery. At the same time, the DLG testers took random samples of the manufactured products and tested these for compliance with defined PAH limits (Conformity of Production). After the certification is awarded to the product qualities and processes defined, an monitoring programme is installed at the Tittmoning production site which involves DLG experts assessing the products and processes for PAH limit compliance on an ongoing basis.

Assessment – Brief Summary

Table 1: Overview of results

Parameter tested Test result DLG requirement
Quality assurance in the manufacturing of floor mats for animal houses The overall impression of the company as gained by the auditors was very good. The company is very quality-conscious and has implemented the quality management system in every aspect. The staff interviewed are knowledgeable and show a high commitment to their individual areas of work. Quality management system in place, applied and adhered
PAH migration to Tenax All rubber blends comply with 15+1 EU SCF-PAH and 8 EU REACH-PAH standards ≤ 10 μg/dm²
(15+1 EU SCF-PAH)
≤ 5 μg/dm² (8 EU REACH-PAH)

The Product

Description and Technical Data

Gummiwerk KRAIBURG Elastik GmbH & Co. KG manufactures rubber mats for cattle, pigs and horses. The mats are used to floor aisles and cubicles. The mats are manufactured from various rubber blends.

All blends were tested for compliance with the quality assurance standards for manufacturing processes and PAH migration (Polycyclic Aromatic Hydrocarbons).

The Method

Assessing the quality assurance measures

The assessment for certifying the production processes at the Tittmoning production site was carried out to ISO 9001:2015.  The manufacturing process was assessed by evaluating the following criteria:

  • Quality systems
  • Responsibilities, authorisations and communication
  • Human resources
  • Procurement of the raw materials
  • Marking and traceability
  • Preservation of product
  • Control of monitoring and measuring equipment
  • Control of defective products
  • Corrective action

PAH migration to Tenax

PAH migration testing was carried out by taking samples from all rubber blends that are produced at the production site. The testing was carried out to the EN 62841-13b standard.


  • Simulating a modified Polyphenylene Oxide (MPPO, Tenax)
  • Contact time: 10 days
  • Temperature: 40 °C
  • Contact surface: 0.5 dm²
  • Quantity: 2 g Tenax

The tests involved cutting a 0.5 dm² patch from the sample and applying 2 g of Tenax powder on it (one-sided contact layer). The weight of each patch was obtained by weighing it on analysis scales. At the end of the contact time, the migrating contact was terminated by removing the Tenax powder from the samples. Then the Tenax was extracted at 40 °C during 24 hours with n-Hexane by adding an isotope-marked PAH standard blend (internal standard) and the n-Hexane extracts were cleaned before the GS-MS measurement was taken using SPE. The test was carried out by applying duplicate measurements.

The Test Results in Detail

Evaluating the quality assurancemeasures

A quality management system is in place and is applied. The criteria tested comply with the requirements. The overall impression of the company as gained by the auditors was very good.

The company is very quality-conscious and has implemented the quality management system in every aspect. The staff interviewed are knowledgeable and show a high commitment to their individual areas of work.

Specific quality standards have been defined and implemented. These ensure that the properties of the products are consistently maintained and no impure raw materials can enter the production process. It was also shown that the manufacturing process ensures no PAH contamination can take place.

PAH migration to Tenax

All rubber blends produced at the site were tested.  PAH migration to Tenax was  found to be less than what is legally permitted. This applies  to all Kraiburg rubber blends tested. Benchmarks: 10 μg/dm² for 15+1 EU SCF-PAH and  5 μg/dm² for 8 EU REACH-PAH


The manufacturing processes of all rubber mats for animal houses made by Gummiwerk KRAIBURG Elastik GmbH & Co. KG at the company’s Tittmoning production site were inspected and assessed.

Also, PAH migration from all manufactured rubber blends to Tenax powder was tested. All criteria tested complied with the requirements.

Applicant and Test implementation


Manufacturer and Applicant
Gummiwerk KRAIBURG Elastik GmbH & Co. KG,
Göllstraße 8,
84529 Tittmoning, Germany

Telephone +49 (0)8683 701-0,
Telefax +49 (0)8683 701-126,

Test implementation

DLG TestService GmbH, Gross-Umstadt location
The tests are conducted on behalf of DLG e.V.

DLG test scope
Quality mark test ‘Project report on PAH migration from rubber floor mats’ provided by Fraunhofer-
Institut für Verfahrenstechnik und Verpackung IVV, Freising, Germany
Checklist used for the assessment in accordance with ISO 9002:2015

Indoor operations

Head of Department
Dr. Michael Eise

Test engineer(s)
Dr. Harald Reubold *

*    Author


DLG TestService GmbH - Groß-Umstadt location • Max-Eyth-Weg 1 64823 Groß-Umstadt Germany • Tel.: +49(0)69 24 788-611 •