I. Standardized Daily Cleaning Specifications
After each operation, clean residual powder inside the chamber immediately with lint‑free soft cloth. High‑pressure air blowing is strictly forbidden to prevent secondary dust dispersion. Carry out full‑scale cleaning and disinfection for inner walls, operating countertops, observation windows and air outlets before daily shift‑off. Clean return‑air passages and dead zones inside the fan chamber every week to avoid material accumulation, bacterial growth and cross‑contamination. Thorough cleaning shall be performed before weighing different materials. Mixing‑material contamination is strictly prohibited.
II. Graded Filter Replacement Standards
- G4 Pre‑filter: Clean or replace every 1‑2 months; shorten the cycle to 1 month under heavy‑dust working conditions.
- F8 Medium‑efficiency filter: Replace every 3‑6 months to prevent clogging of intermediate filter layers that would degrade air volume and negative pressure.
- H14 Supply / Exhaust HEPA filter: Replace every 10‑14 months. Advance replacement shall be performed in case of obvious negative‑pressure drop, reduced air flow or excessive filter resistance, so as to prevent contamination leakage caused by filter failure.
III. Common‑Fault Troubleshooting & Rectification
- Insufficient negative pressure & dust leakage: Check filter clogging, fan air‑volume attenuation and chamber air‑leakage. Replace filters, calibrate fans and repair sealing gaskets.
- Exceeded cleanliness level in working zone: Inspect HEPA filter leakage, uneven laminar air‑flow velocity and incomplete material cleaning. Carry out leakage test and calibration in time.
- Abnormal noise: Caused by fan dust buildup, loose fasteners or component wear. Clean, fasten or replace relevant components.
- Inaccurate differential‑pressure reading: Calibrate differential‑pressure sensor and remove dust deposits on the sensor to guarantee accurate data output.
IV. Compliance‑Oriented O&M Log Management
Maintain complete records including cleaning logs, filter‑change logs, equipment calibration logs and fault‑repair logs. Full‑process traceability shall be achieved to meet routine GMP audit requirements, and eliminate cross‑contamination and compliance risks in powder processing procedures.
