A simple method based on that described in the international standard NF ISO 5017 is implemented to determine the apparent porosity of samples of limestone. Its effectiveness is demonstrated and the points to be particularly controlled (drying, soaking, wiping) to avoid gross errors are highlighted depending on the type of porosity (thin or wide). This study shows that the standard NF ISO 5017 established for dense shaped refractory products is also well suited for solid rock with homogeneous structure having a true porosity of less than 45 %. This standard properly implemented for rock samples allows one to determine their apparent porosity with a standard uncertainty of about 0.1 %.


This paper contains some errors which are reported to n° 38, vol. 2015-2

Key words

apparent porosity
gravimetric method
uncertainty in measurement