ISO 534

Introducing ISO 534 – Industrial Physics

ISO 534 is an international ISO standard procedure for thickness testing, density testing and specific volume inspection of paper and board.

This ISO international standard specifies two methods for measuring the thickness of paper and board using a paper testing micrometer:

• The measurement of a single sheet of paper or board as a single sheet thickness
• The measurement of a pack of sheets of paper as a bulking thickness.

ISO 534 specifies two thickness testing calculation methods to follow. They’ll help you to work out:

• The apparent sheet density and apparent bulk density
• The apparent specific sheet volume and for the apparent specific bulk volume from the thickness determinations.

The methods of ISO 534 aren’t suitable for paper testing of corrugated fibreboard, tissue paper and tissue products.

How to undertake an ISO 534 test

To perform an ISO 534 test you’ll need to measure a single sheet thickness, or of the bulking thickness, using a precision, paper testing micrometer. You can then calculate the apparent sheet density – or apparent bulk density – of the paper or board from a knowledge of its grammage and thickness.

You’ll need to use a dead-weight micrometer – we recommend a digital micrometer. It should have two plane, parallel, circular pressure faces. Your paper or board sample is placed between these faces. The pressure exerted between the pressure faces while thickness testing needs to be (100 ± 10) kPa. The performance requirements of your micrometer include a maximum permitted value indication error of ±2,5 µm or ±0,5 % of the reading.

The paper and board samples that you work with should be prepared in accordance with ISO 186. The conditioning of your sample should be prepared in accordance with ISO 187. On top of this – you need to prepare your test pieces in the same standard atmospheric conditions as those used to condition the sample. You should also avoid any paper or board areas with folds, creases, cracks or other defects which could influence the thickness testing results.

ISO 534 testing devices

So, how can Industrial Physics improve your ISO 534 testing?

The 49-86 Digital Micrometer – a paper specialist

The Digital Micrometer 49-86 quickly and precisely measures the thickness and caliper of most sheet materials – from paper, fabric and films to plastic, metal and leather.

Brought to you by TMI Büchel, our physical property materials testing brand, this reliable digital micrometer is designed for the thinnest of samples. It has a highly accurate measurement range of: 0-0.050in. (0-1.27mm), making it the perfect digital micrometer for paper.

Digital Micrometer 49-56

With the Digital Micrometer 49-56 from Messmer Büchel, our paper testing specialist brand, you’ll achieve accurate thickness measurements of a wide range of sheet-like substrates.

It’s a highly accurate digital micrometer. It offers impressive accuracy within 0.001mm (0.00004in.) or 1% of paper thickness, whichever is better.

PROFILE/Plus Thickness – ISO

For fast and reliable thickness testing measurements in accordance with ISO 534.

Your global test and measurement partner for ISO 534