Use preferably a caliper to measure lengths and a micrometer to measure thickness of rectangular specimens or height of compression specimens.

1. Apply the device (caliper or micrometer) without applying pressure on the dimension you want to measure, especially for soft elastomers.
2. Block the device.
3. Then remove it from the specimen. If you are having trouble removing the device without modifying the measured length, it means that some pressure was applied on it.
4. Write down value. Write down in your lab notebook every measurement performed. And then, next to them, the mean you will input in the software.

1. Measure the height in 3 places evenly distributed along the total circumference. Take the mean.
2. Measure the diameter in 3 places evenly distributed along the height. Take the mean.

Tensile specimens

Tensile specimens are called dumbbell specimens and have this shape:

1. Measure the gauge length 3 times. The gauge length corresponds to the straight part of the specimen with the smallest section. Take the mean.
2. Measure the width in 3 places evenly distributed places along the gauge length. Take the mean.
3. Measure the thickness in 3 places evenly distributed places along the gauge length. Take the mean.