EN 428-1993 pdf download.Resilient floor coverings – Determination of overall thickness.
This EN 428 specifies a method for determining the overall thickness of a resilient floor covering.
2 Definition
For the purposes of this standard, the following definition applies.
overall thickness
the distance between two parallel plates where a resilient floor covering is inserted under a certain load
3 Principle
The test piece is placed between two parallel plates. and the distance between them is measured, the contact pressure being adapted to suit the structure of the test piece.
4 Apparatus
4.1 A mobile circular upper plate. F’or various types of resilient floor covering structures, the diameter of the upper plate, the applied mass, area and pressure shall comply with Table 1.
NOTE For composition cork, the apparatus described in
ISO 9366 using the applied mass and pressure specified in
Table 1 of this standard. may also be used.
4.2 A fixed lower plate at least equal to the size of the
upper plate.
4.3 A comparator to measure the distance between
the plates to an accuracy of 0,01 mm.
5 Samp1in and preparation of test pieces
Take two representative samples from a roll, one from each end or from the beginning of two rolls. From each sample, take a test piece of minimum width 100 mm across the full width of the sample. Take five tiles from the sample as test pieces. Where a pack of tiles comprises the sample, ensure that the first and last tiles are not used as test pieces.
Condition the test pieces at a temperature of (23 ± 2) °C and relative humidity of(50 * 5) % for a minimum of 24 h.
Maintain these conditions when carrying out the test.
7 Procedure
Check whether the plates are clean. Place them in contact with each other and adjust the comparator to zero.
Slide the test piece between the plates and apply the appropriate mass. Apply finger pressure on each side of the upper plate to determine whether it causes the comparator to move. If it does, keep the test piece flat on the lower plate and read the comparator. Read the thickness 5 s after application of the loaded plate.
Take at least 10 measurements for each test piece at a distance of at least 10 mm from the edges.
For tiles, measure each test piece at four positions close to the corners, at a distance of at least 10 mm from the edges.
Record the measured values for each test piece.
8 Calculation and expression of results
Calculate the mean value of thickness from the number of measurements taken and express the result to 0,01 mm.
9 Test report
The test report shall contain the following information:
a) a reference to this standard, i.e EN 428; b) a complete identification of the product tested, including type, source, colour and manufacturer’s reference numbers;
c) previous history of the sample; d) the mean value for overall thickness;
e) the maximum and minimum values for thickness;
f) any deviation from this standard which may have affected the results.EN 428-1993 pdf download.