23. The operator of an establishment where paints or adhesives are manufactured must ensure that the vats used to mix the ingredients are provided with lids that comply with the following specifications:
(1) the lids must be attached to the rim of the vat or the rim of the lids must extend at least 1.3 cm beyond the outer rim of the vat;
(2) the lids must maintain contact with the rim of the vat over at least 90% of the circumference; and
(3) when equipped with an opening to allow for the insertion of a mixer shaft, the shaft clearance must not exceed 5 cm.
In addition, the operator must ensure that the vats are kept covered, except for the time required to fill them, add ingredients or take samples.