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Types of Equipment Covered

The following washer and sterilizer systems require validation in pharma environments:

• Washers: Parts washers, glassware washers, bin/tank washers, automated CIP systems.
• Sterilizers: Steam autoclaves, dry heat ovens, vapor-phase hydrogen peroxide (VPHP), ethylene oxide chambers.
• Combo Systems: Washer-sterilizers used for dual cycles.

Validation must be tailored based on intended use (product contact vs non-contact), cleanroom classification, equipment size, and load complexity. For related validation SOPs, visit PharmaSOP.in.

Validation Approach (IQ, OQ, PQ)

1. Installation Qualification (IQ)

IQ confirms that the washer or sterilizer has been installed according to manufacturer specifications and GMP standards. Activities include:

• Verification of utility connections: electrical, steam, WFI, compressed air
• Material of construction (MOC) checks: SS 316L or 304 for contact parts
• Documentation review: calibration certificates, vendor manuals, wiring diagrams
• Software and HMI configuration validation (if PLC-controlled)
• Spare parts and maintenance log setup

2. Operational Qualification (OQ)

OQ demonstrates that the equipment operates consistently within specified limits. Typical tests include:

• Cycle parameter verification: pressure, temperature, time, flow rate
• Alarm and interlock testing
• Sensor calibration: RTDs, pressure transducers, level sensors
• Empty chamber distribution tests (for sterilizers)
• Spray arm coverage (for washers)

3. Performance Qualification (PQ)

PQ validates the effectiveness of the equipment under actual operating conditions using representative loads:

• Use of biological indicators (BI) such as Geobacillus stearothermophilus for autoclaves
• TOC testing for final rinse water post-wash (≤500 ppb recommended)
• Visual cleanliness inspection (no residue, staining, or particles)
• Worst-case load configuration validation
• Repetition of at least 3 successful cycles

Sample Data: Steam Sterilizer PQ

Load Type	Temp (°C)	Pressure (psi)	BI Log Reduction	Status
Glassware	121.1	15	6.2	Pass
SS Accessories	122.3	16	6.5	Pass
Load with Filters	119.8	14	4.8	Fail

Failed loads must trigger deviation reporting, root cause analysis, and possible requalification or cycle modification.

Key Validation Parameters

During validation, focus should be given to the following measurable parameters:

• Temperature Uniformity: Required for sterilizers. Measured via thermocouples during thermal mapping.
• D-Value and Z-Value: Important for evaluating BI kill rate. D-value of 1.5 minutes is typical at 121°C.
• Spray Coverage and Flow Rate: Evaluated in washers to ensure detergent reaches all surfaces.
• Drain Integrity: Especially for CIP systems to prevent backflow or stagnation.
• TOC and Conductivity: Final rinse must not exceed 500 ppb TOC and 1.3 µS/cm conductivity (WFI standards).

Biological Indicator (BI) Use and Placement

Biological indicators are essential for sterilizer validation. Key considerations include:

• Use BI with ≥10⁶ spores of Geobacillus stearothermophilus.
• Place BIs in the coldest and hardest-to-sterilize locations.
• Include process challenge devices (PCDs) where applicable.
• Perform three consecutive successful runs with no BI growth post-incubation.
• Record exposure time, F₀ values, and BI kill log reduction.

F₀ value of ≥12 is commonly accepted for moist heat sterilization cycles, ensuring sufficient lethality. More info on F₀ calculations can be found at PharmaGMP.in.

Thermal Mapping for Sterilizers

Thermal mapping validates heat distribution across the sterilizer chamber. Protocol:

• Use at least 12–16 thermocouples calibrated and placed at critical points.
• Run mapping with an empty chamber, then with worst-case load.
• Document temperature rise time, dwell time, and cool-down curve.
• Temperature deviation across all points should not exceed ±1°C.
• Worst-case zones identified during mapping are used for BI placement.

Deviation in thermal mapping may require chamber insulation, load redistribution, or sensor recalibration.

Washer Performance Testing

In washer validation, the following key attributes are assessed:

• Detergent Efficacy: Must be validated for soil removal and residue absence.
• Swab Sampling Post-Wash: Conduct swabbing for TOC, residues, and microbial bioburden.
• Visual Inspection: Include criteria for stains, water spots, and discoloration.
• Load Pattern Testing: Validate for worst-case load and coverage.

Washer Load Type	TOC (ppb)	Microbial CFU	Status
SS Scoops & Trays	210	0	Pass
Glass Beakers	470	2	Pass
Complex Fittings	720	10	Fail

Acceptance Criteria

• TOC after final rinse ≤ 500 ppb
• No visible residue on cleaned equipment
• Log₁₀ reduction ≥ 6 for BIs
• Temperature variation ±1°C during sterilization hold
• No microbial growth after 48h BI incubation

Revalidation Requirements

Revalidation of washers and sterilizers should be triggered by:

• Significant changes in load type or volume
• Cycle parameter changes or HMI upgrades
• Equipment relocation or maintenance affecting function
• Recurring deviations or equipment failure
• Annual PQ renewal (for critical equipment)

Common Pitfalls and Regulatory Findings

Regulatory audits often uncover issues such as:

• Missing PQ reports or incomplete cycles
• Unqualified operators modifying parameters
• Inadequate BI placement or documentation
• No linkage between cycle logs and batch release

Proper linking of validation to product quality release is critical. For audit preparation tools, explore pharmaregulatory.in.

Conclusion

Washer and sterilizer equipment validation is a cornerstone of contamination control and regulatory compliance. A systematic IQ/OQ/PQ approach, coupled with robust thermal mapping, biological indicator testing, and performance verification, ensures that these systems operate within defined limits and meet GMP requirements. Document everything thoroughly, address requalification triggers, and maintain ongoing vigilance over cycle performance to remain inspection-ready.

For templates, PQ protocols, and logbooks, visit PharmaSOP.in and StabilityStudies.in.