The paper is devoted to the problems arising during the certification of the standard multifractional sand for cement tests in connection with the new GOST 6139-2020. Amendments to this standard, specifying the requirements to the reference sand used for certification of standard sand, are proposed. Comparative tests of the reference multifractional sand from Normensand GmbH (Germany) with one of the standard sands available on the market of the Russian Federation were carried out.