These guidelines introduce the principles, testing and assessment of corrosion of refractories by liquids (molten metals, metallurgical slags, glasses, fluxes etc.) and describe four commonly used test methods.- Method A: Corrosion testing by the crucible test;- Method B: Corrosion testing by the finger-dip test;- Method C: Corrosion testing by the rotary slag test;- Method D: Corrosion testing by the induction crucible test.