Pass-through chambers play a key role in contamination control by allowing materials to move between rooms without disrupting pressure relationships or exposing clean areas to unnecessary traffic. Whether used in an ISO-classified cleanroom, a pharmaceutical production suite, or a USP <797>/<800> compounding facility, keeping pass-throughs clean and functioning properly is essential to maintaining environmental control.
Why Pass-Throughs Matter in Controlled Environments
A pass-through chamber minimizes personnel movement, reduces door openings, and provides a controlled method for transferring materials. Depending on the design, pass-throughs may incorporate:
- Mechanical or electronic interlocks
- Stainless steel or seamless internal finishes
- HEPA‐filtered airflow (for ventilated models)
- Flush-mount windows and cleanability features
While they are not infection control devices, they support overall contamination control by helping maintain pressure differentials, limiting particle migration, and reducing contact with critical areas.
Cleaning & Disinfection Frequency
Cleaning requirements depend on:
- The type of controlled environment
- The materials transferred
- Facility SOPs and manufacturer instructions
A common industry approach includes:
Daily (or per shift)
- Wipe-down of internal surfaces
- Disinfection of touch points, latches, and door seals
- Use of 70% IPA or an approved disinfectant compatible with cleanroom materials
Periodic Sporicidal Application
- Applied at intervals defined in the facility’s SOP (often monthly or quarterly)
- May include agents such as hydrogen peroxide, peracetic acid, or chlorine-based disinfectants
- Intended to reduce spore-forming organisms in critical environments
After Maintenance or Spills
Any time the chamber is serviced, adjusted, or contaminated during use, it should be cleaned and disinfected before returning to operation.
Follow Facility Requirements
USP <797>/<800> and ISO cleanroom programs require that all surfaces within classified or controlled environments, including pass-through chambers, be cleaned and disinfected at defined frequencies and fully documented. The exact intervals must follow the facility’s written cleaning SOPs.
How Pass-Through Chambers Are Evaluated During Certification
While cleaning falls under the facility’s SOPs, performance verification typically occurs as part of routine environmental certification. Depending on the design, this may include:
- Door Interlock Testing – Ensuring only one door can open at a time and that safety interlocks function as designed.
- HEPA Filter Integrity Testing (for ventilated pass-throughs) – Leak testing of installed filters to verify they meet ISO and IEST performance criteria.
- Airflow Verification – Confirming airflow direction and volume where applicable, including verification of negative or positive pressure relationships between adjoining rooms.
- Surface & Environmental Monitoring – Facilities may perform viable surface sampling or include the pass-through area as part of their routine EM program to verify the effectiveness of cleaning.
The TSS Difference
While facilities manage the cleaning and disinfecting of pass-through chambers, TSS provides the certification, testing, and environmental monitoring services that verify these systems continue to operate safely and as intended.
TSS supports clients with:
- ISO cleanroom certification
- USP <797>/<800> room and PEC certification
- HEPA filter integrity testing
- Airflow visualization and containment testing
- Environmental monitoring programs
- Door interlock and equipment functional checks
For nearly 50 years, TSS has partnered with healthcare, research, biotech, and pharmaceutical organizations to ensure cleanrooms and critical environments remain compliant, safe, and ready for inspection.
