The “PSA D45 1195 Thickness and Compressibility of Flexible Materials” standard, developed by the French automotive manufacturer PSA Group (now part of Stellantis), describes a method for measuring the nominal thickness of a compressible flexible material. This method also includes an assessment of the material's compressibility. This method is applicable to flexible materials such as textiles, coated textiles, leather, fillers, and the like.
This standard is based on the “A10 0156 Measurement or test reports - Drafting” standard.
In principle, the thickness of a flexible material is the distance, measured in micrometers, between two planar and parallel contact points. During processing, the sample is subjected to a specific pressure between these contact points.
This method uses two circular flat-tipped micrometers: one movable with a diameter of 50 mm (according to the instructions in the reference documents) and one fixed with a diameter greater than 50 mm. These two tips are parallel and their axes of rotation coincide. The pressure applied by the movable tip can be 1, 5, 10, 20, 50, or 100 hPa (i.e., approximately 1, 5, 10, 20, 50, or 100 g/cm²) up to the nearest 5 percent according to the relevant standards. This process also uses a climate-controlled room with a temperature of 23 degrees plus/minus 1 degree and a relative humidity of 50 percent plus/minus 5 percent. Acetone or any other solvent that allows initiating separation between the layers is used as the reactant.
Test specimens must be representative of the scale being characterized. To ensure this representativeness, it is necessary to determine the baseline characteristics of the population being studied. The selection criteria for the test specimen(s) should be stated in the test report in accordance with standard A10 0156. If there is any doubt about sampling, PSA should be contacted for further guidance.
When processing samples, at least 5 samples measuring 100 mm x 100 mm are taken for relatively homogeneous materials such as felt, coated or uncoated textiles, and leather, while 10 samples are taken for heterogeneous materials such as impregnated cotton. The samples are divided into zones at least 50 mm apart from each other and at least 100 mm from the edges of the part. The samples are allowed to stand in the chamber for at least 24 hours, after which measurements are taken in the same chamber. When measuring various layers of a complex, these must be separated.
During processing, the thickness of the material can be measured directly on the part made of the material at 5 different points for homogeneous materials and 10 different points for heterogeneous materials. Thickness measurements can be performed at any point and in any area of the part, leaving a 50 mm gap between each measurement point. However, it is recommended to stay at least 20 mm away from the edge to prevent the edges of the parts from being pinched in relation to cutting or stitching. The part is allowed to rest in the room for at least 24 hours, after which the measurements are performed in the same room.
When measuring nominal thickness, the micrometer is set to the selected measuring pressure. The reverse side of the part or sample is placed on the fixed contact tip of the micrometer. The movable contact tip is slowly lowered, avoiding any impact. The movable contact tip is left in contact with the material for 10 seconds under the required pressure, after which the reading from the micrometer is taken.
When determining compressibility, the device is set to a measurement pressure 10 times higher than the pressure used in the previous measurement. The thickness of the material is measured according to the conditions described above. This measurement can be performed on samples that have already been tested.
The nominal thickness, expressed in millimeters, is the arithmetic mean of the measured values, assigned an index equal to the value of the measured pressure. The thickness under load is expressed in millimeters, assigned an index equal to the value of the measured pressure, and the arithmetic mean of the measured values is taken. The compressibility of the material is calculated according to a formula given as a percentage.
In short, the PSA D45 1195 standard primarily targets soft, compressible materials used in automotive applications. These include:
These materials contribute to comfort, noise reduction, and safety in vehicle cabins. Therefore, consistent thickness and compression behavior are critical for quality and performance.
The PSA D45 1195 standard test evaluates how these materials behave under pressure:
This ensures that the parts fit together properly during assembly, maintain their shape over time, and perform reliably under real-world conditions such as passenger weight or vibrations.
In the automotive industry, manufacturers aim to achieve the following by demanding strict requirements from suppliers through standards such as PSA D45 1195 and similar standards:
In conclusion, the PSA D45 1195 standard is not just a product standard, but a fundamental engineering standard that ensures the reliability of everyday materials inside vehicles. This standard is part of a broader family of PSA D45 standards that covers material properties such as heat resistance, combustion behavior, and tear strength. For suppliers or engineers working with PSA/Stalantis, compliance with this standard is often mandatory for part approval.
For many years, our organization, with its competent and experienced staff, has been understanding the needs of its customers, providing the advanced testing services they require, and assisting in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services to businesses in accordance with the "PSA D45 1195 Thickness and compressibility of flexible materials" standard.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
