Decontamination factors (DF) for the VL-501 stainless steel samples contaminated with radioisotopes. Modifications of the VL-501 composition: 0 – no; 1 – oxalic acid; 2 – Trilonom-B; 3 – citric acid; 4 – nitric acid; 5 – hydrochloric acid; 6 – ammonium chloride; 7 – aluminum chloride; 8 – oxyethylidenediphosphonic acid