Barometers Illegal in Garbage & Drains Contains Mercury Hazardous Waste Items containing mercury (including barometers, Coulter counters, manometers, thermometers, thermostats and switches) must be inspected by EHS prior to transportation to salvage. Contact your Division Liaison to involve Hazards Control from EHS for this process. Items must be in good condition & able to be handled without leaking. Never Throw Away Most antique barometers contain about 4 ounces of mercury. If your barometer contains mercury, it can be toxic to landfills, so dispose of it with hazardous waste.