Trumpy, that’s not an easy situation to deal with. In some cases safety and productivity are thought of as mutually exclusive, but when you’re assigned to work with someone that causes serious degradation to both, he is not the only one who is affected. In the US, with so such “deep pockets” litigation, your employer may have to deal with major repercussions for even minor misdeeds, if he is discovered working in an impaired state.
A hard decision to make is how much you discuss with him before you “elevate” the situation. {That is, take the problem to your managers.}
Some companies in this area have voluntary substance-abuse counseling programs… any chance your firm does? He will not likely be able to get through this without some specialized help.
Be careful—you don’t want to be blamed for his actions, or inactions in treating his problem.
