PURPOSE: To assure safe storage and segregation or waste chemicals
DATE OF ISSUANCE: 2/28/97 
The proper segregation of waste chemicals is essential to promote safe storage of those chemicals as well as to facilitate the economical disposal of the chemicals. The Environmental Protection Agency (EPA) has published a list of potentially incompatible wastes, waste components, and material along with the harmful consequences of mixing those materials together. This list does not include every possible hazardous chemical reaction, but should be used as a guide in packaging and storing these materials. The list indicates the potential consequences of the mixing of a Group A material with a Group B material. These compatibility listings should not be the only information used when packaging or accumulating waste chemicals. Pay close attention to any waste characterization data you receive on material reactivity and compatibility. Material Safety Data Sheets contain a section devoted to chemical reactivity and incompatibility. The following lists of chemicals in Groups A should be kept separate from those chemicals in Groups B:
| Group A | Group B | 
|---|
| Group 1-A  
BasesPotential consequences:  Heat generation; violent reaction | Group 1-B | 
| Group 2-A 
AluminumBerylliumCalciumLithiumMagnesiumPotassiumSodiumZinc powderOther reactive metals and metal hydridesPotential consequences: Fire, Explosion, or generation of flammable hydrogen gas. | Group 2-B | 
| Group 3-A 
AlcoholsWaterPotential consequences: Fire, Explosion, or heat generation: generation of flammable or toxic gases.
 | Group 3-B 
Any Concentrated Acids or BasesCalciumLithiumMagnesiumSodiumZinc PowderAny Reactive Metals and Metal HydridesPotassiumSulfonyl chlorideThionyl chloridePhosphorus trichlorideMethyl trichlorideMethyl trichlorosilaneOther water-reactive waste | 
| Group 4-A 
AlcoholsAldehydesHalogenated hydrocarbonsNitrated hydrocarbonsUnsaturated hydrocarbonsOther organic compounds and solventsPotential consequences:  Fire, Explosion, or violent reaction. | Group 4-B 
Any Concentrated Acids or BassesReactive Metals and Metal Hydrides | 
| Group 5-A 
Cyanide's and sulfide'sPotential consequences:  Generation of toxic hydrogen cyanide or hydrogen sulfide gas. | Group 5-B | 
| Group 6-A 
ChloratesChlorineChloriteschromic acidHypochloritesNitratesNitric acid, fumingPerchloratesPermanganatesPeroxidesOther strong oxidizersPotential consequences:  Fire, Explosion, or violent reaction. | Group 6-B 
Acetic acid and other organic acidsConcentrated mineral acidsReactive Metals and Metal HydridesOrganic Compounds and SolventsOther flammable and combustible chemicals | 
| The following two groups are added to facilitate the economical disposal of the wastes.  They are not necessarily reactive. | 
| Group 7-A 
Heavy metal Compounds containing arsenic, barium, cadmium, chromium, lead, selenium, silverPolychorlinated biphenyls (PCBs) DioxinsMercury Containing Compounds | Group 7-B | 
| Group 8-A 
Polychlorinated biphenyls (PCBs)DioxinsMercury Containing Compounds | Group 8-B 
All other chemicals and each other |