
A system for inhibiting use of a hand-operated machine by an impaired individual through detection of toxins in the individual has affixed to a portion of the machine which the operator regularly engages with his or her hands a porous membrane (5) impregnated with a substance (2) which reacts with a toxin by-product of an impairing substances such as alcohol, and another substance which causes the combined toxin and toxin-reacting substance to exhibit a color change. The system further contains ...











