Validate Hold Times for Sterilized Garments Used in Cleanrooms
Remember: Always validate how long sterilized garments remain sterile under storage conditions — this ensures aseptic integrity during GMP operations.
Why This Matters in GMP
Sterilized garments used in Grade A/B cleanrooms play a vital role in protecting products from personnel-borne contamination. After sterilization, garments are stored until needed for use. If the hold time — the duration garments remain sterile and suitable for use — is not validated, microbial breach or loss of sterility may occur. Environmental conditions such as humidity, handling, and storage practices can impact microbial barrier performance over time.
For instance, a sterile coverall stored beyond its validated hold time may no longer provide reliable aseptic protection, especially if the packaging degrades or microbial barrier integrity is compromised. Without validation, operators may unknowingly gown with garments that have exceeded their safe usage window, exposing sterile zones to contamination risks.
Regulatory and Compliance Implications
21 CFR Part 211.28 emphasizes personnel hygiene and protective measures to prevent contamination. EU GMP Annex 1 requires that sterilized garments be stored and used within validated conditions and timeframes. WHO GMP also highlights the need for documented controls
Inspectors assess sterilization logs, gown storage conditions, and hold time validation protocols. If expired or unvalidated garments are found in gowning areas, it may result in major observations concerning contamination control, lack of validation, and sterile assurance breaches.
Implementation Best Practices
Conduct a hold-time study for sterilized garments that simulates real storage conditions — temperature, humidity, and light exposure. Test microbial barrier integrity and sterility maintenance over defined durations (e.g., 7, 14, 30 days). Validate garment packaging performance and environmental storage conditions (e.g., cleanroom or controlled area).
Label sterilized garments with sterilization date, expiry/hold limit, and lot number. Store them in clean, segregated, and monitored zones. Train personnel to check expiry before gowning. Incorporate hold-time limits into gowning SOPs, inventory systems, and QA review processes.
Regulatory References
– 21 CFR Part 211.28 – Personnel clothing and hygiene
– EU GMP Annex 1 – Cleanroom gowning and sterile assurance
– WHO TRS 961, Annex 6 – Gowning procedures and hold times
– PDA TR #70 – Gown Management in Aseptic Processing