Long-term storage of hydrogen peroxide at room temperature can cause it to decompose, creating over-pressurization and container failure. It is recommended that concentrated hydrogen peroxide be refrigerated to reduce the decomposition rate.
Waste management encompasses more than environmental compliance. Putting chemicals into waste containers doesn’t neutralize them. They can still decompose readily or react with each other. Mixing strong oxidizing / reducing agents with other substances can cause violent reactions, producing gases that can cause over-pressurization and even container failure.
Research staff members are responsible for evaluating and understanding the chemistry of waste streams, using caution during handling, segregating incompatible materials, and disposing of wastes properly.
Effects of Incident
A researcher discovered two shattered bottles of 1-butanol in a laboratory flammable storage cabinet. Additionally a bottle of acetone was damaged as well as a plastic containment tub. The materials captured in the cabinet’s secondary containment pan amounted to about eight liters. There were no injuries associated with the incident
Investigators determined that the direct cause of the spill was a glass waste bottle containing hydrogen peroxide, sulfuric acid, sodium nitrite and water.
The materials decomposed inside the tightly sealed bottle, building up pressure, and causing the bottle to rupture. The force damaged two bottles of 1-butanol, a bottle of waste acetone, and the cabinet’s plastic containment tub. It is unknown how long the rupture and spill had gone undetected. The cabinet had not been accessed for nearly a month and the waste bottle had been tightly sealed for about nine months.
The damaged bottle of acetone stored in the same cabinet was a concern. If hydrogen peroxide and sulfuric acid had mixed with the acetone, the reaction could have created acetone peroxide--a shock-sensitive and potentially explosive chemical.
At room temperature, the addition of 230 mL of hydrogen peroxide to a waste bottle that contained sulfuric acid, sodium nitrite and water stepped up the decomposition rate of the hydrogen peroxide and created enough pressure in the tightly sealed bottle to cause it to burst.
Hydrogen peroxide is known to decompose and create hazards. In this case, the decomposition process was accelerated by impurities. Other incompatible materials can react violently, liberating gas and causing over-pressurization of containers. Classic examples include mixing cyanides or sulfides with mineral acids. Research staff members must be aware of groups of materials in their labs that could be incompatible.
Corrective Actions to Prevent Reoccurrence
Consider and adopt appropriate safety practices for the handling and storage of hydrogen peroxide and other oxidizing/reducing chemicals. For example, use vented or loose caps, pressure release valves, neutralize prior to storage as waste, use plastic containers that can bulge as a warning before failing under pressure.
Store pure hydrogen peroxide at greater than 30 percent concentration in a refrigerator segregated from other organic reagents. Concentrations of hydrogen peroxide at less than 30 percent can be stored at room temperature, but follow manufacturer’s directions.
Recognize that flammable storage cabinets are not intended to house incompatible chemicals.
Take responsibility for waste containers in a satellite accumulation area (SAA). The most knowledgeable person--usually the one who generates waste--is responsible and accountable for waste containers in an SAA.