Commercial Fixed Wing
Maintenance Airframe; Maintenance Powerplant
Training / Qualification
Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Procedure; Human Factors
Two mask assemblies were sent for aircraft being worked by Maintenance in ZZZ at Hangar X. A box of unused parts were returned to stores and placed on the serviceable shelf outside the stores area. I shipped the parts back to ZZZ1 which is where ZZZ returns unused parts. I was recently made aware that the mechanics working the aircraft used one of the parts and replaced in the box the used parts which is a Passenger Service Unit and HazMat; and left the tag for parts on the box when they sealed the box before returning the parts to stores. So; I accidentally shipped a HazMat as unregulated on Flight ZZZ to ZZZ1 under waybill. Under the circumstances; and being made aware of the ability to self-disclose; I thought it best to report this incident and; bring the matter to your attention. I deeply regret the error and apologize for the concern I've caused and will be more vigilant in the completion of my duties. The used hazardous part was misplaced inside a box prelabeled for a non-hazardous part; sealed; placed with serviceable parts; and placed in an area marked for serviceable parts. Open any and all boxes both serviceable and unserviceable and verify what is inside the box matches with both the paperwork and the labeling on the box before proceeding to shipping or receiving.
Maintenance Technician reported inadvertently shipping Hazmat parts in Non-Hazmat container.