Date: 201905
Location: ZZZ.Airport, US
Aircraft: B777-200
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Aircraft component: Waste Water Disposal System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Technician
Reporter qualification: Maintenance Powerplant; Maintenance Airframe
Human factors: Situational Awareness; Physiological - Other
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Maintenance
When detected: Other Routine Maintenance
Result: General Physical Injury / Incapacitation
Contributing factors: Procedure; Equipment / Tooling; Human Factors; Environment - Non Weather Related
Primary problem: Procedure

Narrative: I was assigned to the Vacuum Waste Tank Liquid Separators/Filters Replacement on the Aft Waste Tanks during an A-check for a/c XY12 in ZZZ. I completed the job with another technician who was also assigned; without incident; wearing the PPE listed in the work card. Later that evening and in the days following I began to feel cold/flu like symptoms that were getting worse by each day. Finally upon arriving to work [a few days later]; I asked my supervisor if I could go seek medical treatment and get checked for any serious viral infections given the exposure I had to harmful bacteria from working on the waste systems. I checked in to hospital and was examined and given a blood test which didn't show any signs of abnormal viral infection. I was soon after released with a doctor's note stating when I should be able to return to work. I'm still recovering from this illness. It is pretty common for those of us who do this job to become ill shortly afterward. I am lucky I did not come down with anything serious.The job work card Vacuum Waste Tank Liquid Separators/Filters Replacement lists several pieces of personal protective equipment that may be used in performing this job; however; none of them include an air respirator mask or full Hazmat suit; both of which should be required. The aft cargo bin where the Waste Tanks are located is a very confined area and has no ventilation. As soon as the tanks filters are removed the highly concentrated bacteria inside gets airborne and stays in the cargo bin. The dust masks the company currently provides are not nearly enough protection from inhalation of the tank fumes. The white body suits we are provided with are also not enough protection since the skin on our chest and neck area is exposed to the air. A full Hazmat suit should be necessary. Also; in the B777 manual it states air ventilation equipment is necessary to be attached to any aircraft's vacuum system exhaust in the hangar if aircraft waste systems are operated. I do not believe we have this equipment in ZZZ station. I don't have any suggestion on how to ventilate/disinfect the cargo bin area; which I also think is necessary since the bacteria can't escape after we've concluded the filer replacement and closed the cargo walls. Ramp personnel are also at risk of exposure when they load the plane for the next flight.




Synopsis: B-777 Technician reported illness as a result of work assignment of vacuum waste tank liquid separator/filter replacement. Reported strongly recommended the need for improved protective clothing and respirator equipment.