Metal Detector (Tablet/Capsule Stage) Validation Overview

Introduction to Metal Detector Validation for Oral Solid Dosage Forms

In modern oral solid dosage (OSD) manufacturing, metal detectors play an essential role in ensuring product safety and regulatory compliance. Metal detector validation, specifically at the tablet or capsule stage, is a critical activity in the pharmaceutical industry’s Good Manufacturing Practice (GMP) environment. Metal detectors are installed after tablet compression or encapsulation and often prior to final packaging, serving as a last line of defense against inadvertent metallic contamination. Understanding the scope, criticality, expectations, and practical approaches for metal detector validation is fundamental for pharmaceutical manufacturers seeking to guarantee the safety and quality of their products.

Role and Purpose of Metal Detectors in OSD Manufacturing

Metal detectors are designed to remove contaminated tablets or capsules containing ferrous, non-ferrous, or stainless steel particles. Positioned downstream of compression or encapsulation equipment, but before packaging, their intended use is narrowly defined: they must reliably detect and reject product units contaminated with metal particles that may originate from upstream equipment wear, operator error (such as dropped tools), or raw material contamination. Metal detectors are not intended as a replacement for thorough equipment maintenance or upstream controls; instead, they serve as a critical control point in a multilayered contamination prevention strategy.

The boundaries of intended use do not extend to the detection of non-metallic contaminants, assurance of all foreign matter absence, or as batch release decision points; rather, their primary function is safeguarding finished product integrity by capturing potential metallic hazards immediately before packaging.

Validation and Qualification Scope

A comprehensive metal detector validation program incorporates a systematic evaluation of the equipment’s capabilities, the reliability of its rejection mechanism, and ongoing process integration. Defining the scope and boundaries of qualification activities is essential for efficient validation execution and regulatory audit readiness.

In-Scope Activities:

• Installation Qualification (IQ) – Verifying correct installation and setup according to manufacturer’s instructions.
• Operational Qualification (OQ) – Confirming the metal detector can reliably detect predefined test pieces (Fe, Non-Fe, SS) at specified sensitivities under controlled conditions.
• Performance Qualification (PQ) – Demonstrating that the detection and rejection functions operate effectively under simulated or actual process conditions with representative product lots.
• Challenge testing protocols – Routine sensitivity checks to ensure ongoing operation within validated parameters.
• Data integrity checks – Ensuring audit trails, batch records, and calibration records are generated, secured, and reviewed appropriately.

Out-of-Scope Activities:

• Evaluation of non-metallic or non-conductive contaminants (e.g., glass, plastic).
• Facility-wide environmental monitoring – except as it directly impacts detector performance.
• Downstream packaging operations validation, unless they affect the detector’s performance zone.
• Supplier’s internal assembly process validation (beyond factory acceptance testing reports as supplied).

Criticality Assessment: Impact on Product, Patient, and Operations

Assessing the criticality of metal detectors within OSD manufacturing is a prerequisite for determining the depth of validation and control measures required.

• Product Quality Impact: Failure to detect metal could introduce hazardous contamination, directly affecting product quality and compliance.
• Patient Risk: The presence of undetected metallic fragments can result in injury, choking, internal bleeding, or even toxicity if ingested with the medicinal product.
• Data Integrity Impact: Inaccurate or incomplete detector audit trails, calibration, or challenge logs can compromise batch release and regulatory defenses.
• Contamination Risk: Metal contamination typically indicates an upstream breakdown (equipment wear, maintenance lapses) and has the potential for batch-wide failure.
• EHS Risk: Undetected or improperly rejected metal pieces could damage downstream packaging equipment, introduce maintenance hazards, or result in product recalls with associated reputational and legal exposure.

Key GMP Expectations for Metal Detector Validation

Regulatory inspectors expect that metal detectors within GMP OSD workflows are qualified, calibrated, and operated within validated ranges. Key GMP requirements demand:

• Clearly defined equipment operating ranges (detection limits by metal type and size).
• Full documentation of controls in SOPs – from setup, calibration, and challenge test scheduling, to troubleshooting and maintenance.
• Traceable calibration and challenge records for every production lot.
• Documented rejection verification (e.g., physically retrieving rejected tablets/capsules) during ongoing production.
• Change control for any equipment modification or relocation affecting critical functions or detection abilities.
• Secure, tamper-evident audit trails for electronic recordkeeping, consistent with current data integrity expectations.
• Qualified and trained operators responsible for detector checks and documentation review.

Approach to Writing a Metal Detector User Requirements Specification (URS)

The User Requirements Specification (URS) defines what the metal detector must achieve and the critical functions it must fulfill. A robust URS informs the equipment selection, design qualification, vendor assessment, and forms the foundation for risk assessment. Key sections in a metal detector URS relevant to OSD include:

• Product Scope: List the tablet/capsule types, sizes, and physical characteristics.
• Detection Performance: Required sensitivity levels for various metals (e.g., Fe, Non-Fe, Stainless Steel), with units (mm).
• Throughput Requirements: Specify speed or capacity (e.g., tablets/hour).
• Integration: Mechanical and electronic interfaces with upstream and downstream equipment.
• Rejection Mechanism: Criteria for positive rejection (e.g., pneumatic diverter) and tamper-proof rejected sample collection.
• Data Integrity and Audit Trail: 21 CFR Part 11 compliant event logs and user access controls.
• Calibration and Self-Test Features: Automated and manual test triggers, frequency requirements.
• EHS and Compliance: Cleanability, noise/EMC, risk mitigation requirements.

Example: URS Excerpt for Tablet Metal Detector

• Detect Ferrous at ≤ 0.7 mm, Non-Ferrous at ≤ 0.9 mm, Stainless Steel at ≤ 1.2 mm.
• Compatible with tablet sizes 5–20 mm diameter and up to 8 mm thickness.
• Rejects detected tablets within 0.5 seconds with validated pneumatic diverter.
• Audit trail records all alarm events, test results, and user interventions, protected against unauthorized changes.
• Throughput: Minimum 180,000 tablets/hour, continuous operation, ≤1% false reject rate.

Risk Assessment Foundations in Metal Detector Validation

Effective metal detector validation hinges on risk-based thinking. Applying Failure Mode and Effects Analysis (FMEA)-style assessments helps prioritize the risks to product quality or patient safety, and shapes qualification approaches.

Typical risk assessment steps include:

1. Identify possible failure modes (e.g., non-detection, false rejection, rejection mechanism jam, calibration drift).
2. Assess the severity, probability, and detectability of each failure in the context of the manufacturing process.
3. Define appropriate control or mitigation strategies (e.g., increased challenge frequency, real-time alarms, interlocks, preventive maintenance scheduling).
4. Develop qualification and test plans to challenge critical functions under normal and stressed conditions.

By linking each critical requirement to specific risks and defined controls or tests, the qualification plan becomes actionable and defensible.

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Supplier Controls for Metal Detector Validation

Effective metal detector validation at the tablet/capsule stage of oral solid dosage (OSD) manufacturing begins with robust supplier controls. Every GMP-compliant process expects that qualified vendors deliver equipment that meets strict pharmaceutical standards. The supplier qualification process involves multiple layers of diligence, impacting system integrity and ensuring long-term validation continuity.

1. Vendor Qualification

• Pre-audit and Evaluation: Evaluate the supplier’s quality management systems, compliance with ISO 9001 or ISO 13485, and specific experience with OSD pharmaceutical equipment. Third-party audits or site visits are recommended.
• Reference and Performance Assessment: Assess the track record for delivering validated metal detectors for similar GMP-regulated environments. Confirm established technical support and service network access.
• Supplier Approval: Maintain supplier approval status and periodic requalification aligned with changing regulatory requirements or critical deviations.

2. Supplier Documentation Package

The supplier must deliver a comprehensive documentation package, critical for seamless qualification and ongoing support:

• Certificates of Compliance: Include material certificates for contact and non-contact parts, surface finish documentation, and elastomer certificates (e.g., FDA/EP compliance for gaskets).
• Drawings and Schematics: Final “as-built” drawings, P&IDs (where applicable), wiring diagrams, and electro-mechanical assembly details.
• User Manual: Operation, cleaning, and maintenance instructions supporting compliant, traceable use.
• Software Documentation: If equipped with embedded software or PLC/HMI controls, a validated software release note, copy of the installed software, version control log, and a clear change management record are essential.
• Factory Test Reports: Pre-dispatch functional and calibration reports showing compliance with specified limits.
• Calibration Certificates: For all critical sensors (e.g., rejection mechanism sensors, limit switches, load cells for checkweighers paired with metal detectors).

3. FAT (Factory Acceptance Test) and SAT (Site Acceptance Test) Strategy

Acceptance testing forms a vital bridge between supplier commitments and user requirements. A well-designed FAT/SAT protocol for metal detectors addresses both performance and GMP-specific needs.

FAT Focus Areas

• Test Scope: Electronic stability, automatic balance function, rejection mechanism operation, detection sensitivity for different metals (ferrous, non-ferrous, stainless steel), and alarm/record systems.
• Documentation: Record all test data, calibration records, and deviations. Verification checks should be referenced against the URS and RFQ specifications.
• Witnessing: FAT is witnessed by user QA/QC specialists, engineering, and often a validation SME or consultant. Third-party inspection may be included per quality agreements.
• Handling Deviations: Deviations must be clearly documented, investigated for root cause, risk-assessed, and resolved prior to shipment or deferred with documented impact/risk analysis and a closure plan.

SAT Focus Areas

• On-Site Verification: Focuses on “as-installed” function: utility integration, installed cable runs, alignment with adjacent process streams, performance retest using challenge tablets/capsules, and interlocks with upstream/downstream systems.
• Acceptance Criteria: Must match FAT unless revalidated due to site-specific changes. Record SAT results with sign-off by end-users and quality/validation representatives.

4. Design Qualification (DQ) for Metal Detectors

DQ ensures the chosen metal detector model meets all GMP, regulatory, and process requirements for OSD applications.

• Design Review Sessions: Review of all key URS requirements including detection thresholds, production rates, integration with tablet press/capsule fillers, and compliance with relevant safety standards (CE, UL).
• Drawings/Documentation: Cross-verification of component layout, belt/track design, rejection system, and software control architecture with the process flow and line clearance strategies.
• Materials of Construction: Confirm pharmaceutical-grade stainless steel (typically 304/316L for product contact), compatibility with cleaning agents, and avoidance of reactive alloys or hazardous polymers.
• Hygienic Design Elements: Smooth surfaces for easy cleaning, open design for visual inspection/maintenance, absence of dead legs, and validated cleaning procedures for product contact areas.

5. Installation Qualification (IQ) for Metal Detector Systems

IQ systematically proves that the metal detector has been installed as per DQ and supplier drawings, with all ancillary connections and documentation in place.

• Physical Installation: Mounting integrity, correct positioning relative to the product stream, and secured fixings.
• Utilities: Correct installation and adequate rating of electrical supply (including power quality), grounding, and any required air lines for pneumatic rejection mechanisms. Utility allocation checks against approved floor plans.
• Instrumentation and Sensors: Verification of sensors/interlocks (e.g., reject confirmation, jam detection), operational status, and calibration certificates traceable to standards.
• Labeling: GMP-compliant identification tags, warning/operational labels, and unique equipment identification as per plant SOPs.
• As-Built Dossier: Compilation of signed-off “as-built” drawings, installation log, change control records (if deviations occurred), and photographic evidence where appropriate.
• Safety Checks: Verification of safety guards, e-stop circuits, safe access for maintenance, and emergency procedures.

6. Environmental and Utility Dependencies

Metal detector performance is significantly affected by environmental and utility quality in oral solid dosage settings. Relevant dependencies include:

• HVAC Classification: Detectors installed post-compression or encapsulation typically require ISO 8 / Grade D area minimum. Airborne particulates and humidity directly impact electronics and detection reliability.
• Compressed Air: For pneumatic rejection, air must meet ISO 8573-1:2010 Class 2–4, oil-free, with point-of-use filtration validated at the detector. Output pressure and absence of moisture/oil are key acceptance factors.
• RO/PUW and Steam: Not directly connected for metal detectors, but cross-contamination risks from adjacent cleaning-in-place (CIP) operations should be assessed; documentation of spatial segregation is part of DQ/IQ.
• Electrical Power Quality: Stable single-phase/three-phase power (as specified in URS), surge/spike protection, and proper grounding to avoid nuisance tripping or loss of sensitivity.

Traceability Table: Requirements to Acceptance

Supplier & DQ/IQ Document Checklist

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Operational Qualification (OQ) of Metal Detectors in Oral Solid Dosage Production

During the validation of a metal detector installed at the tablet or capsule stage of an oral solid dosage form (OSD) process, the Operational Qualification (OQ) phase holds significant importance. OQ focuses on confirming and documenting that the metal detector operates consistently and reliably within all specified functional ranges, under simulated or expected process conditions. This phase ensures that the equipment fulfills its intended purpose of detecting and rejecting metal contaminants, thereby securing GMP compliance and safeguarding product quality.

OQ Execution Steps for Metal Detector Validation

The OQ phase involves carefully planned activities, systematically executed in accordance with written protocols and reference standards. For OSD lines, metal detectors at the tablet/capsule stage require particular attention to:

• Functional operation: Verifying all detection and rejection mechanisms.
• Acceptable operating ranges: Assessing performance at upper and lower setpoints.
• Alarms and interlocks: Confirming safety and control interlocks are functional.
• Data integrity (if automated): Checking computerized system controls for secure data handling and compliance.
• Instrumentation and calibration verification: Ensuring detectors and sensors are accurately calibrated and within tolerances.

Key Functional Tests in OQ

• Detection Sensitivity Verification:
  • Challenge the metal detector with calibrated test pieces—ferrous, non-ferrous, and stainless steel—embedded in placebo or actual tablets/capsules.
  • Run tests at the center and sides of the conveyor/chute to check for edge effect and sensitivity uniformity.
• Reject Mechanism Functionality:
  • Confirm that the reject flap, pusher, or directed air blast reliably isolates metal-contaminated units.
  • Ensure rejected units are diverted to a locked, labeled, and segregated collection bin.
• Alarm and Reject Confirmation:
  • Trigger alarms through challenge pieces. Visual and/or audible alarms must activate instantly, and associated system responses (like line shutdown or indicator lights) must be verified.
• Failsafe and Interlock Verification:
  • Simulate power loss, sensor failure, or reject bin full/door open conditions to observe if the system correctly inhibits operation and records the event.
• Setpoint Verification:
  • Document the minimum-detectable sizes for each metal type and verify capability across declared setpoints. For example, sample acceptance criteria might be "Ferrous: 0.7 mm, Non-Ferrous: 0.8 mm, Stainless Steel: 1.2 mm".

Instrumentation Checks & Calibration Status During OQ

All instrumentation critical to the function of the metal detector, including electromagnetic sensors, input/output control modules, pressure switches (if pneumatic operation is involved), and any process monitoring devices, must be verified as calibrated. Calibration certificates should be traceable, current, and referenced in the OQ documentation. During OQ, verify:

• Calibration stickers/labels are present and within validity dates.
• Signal strength and baseline noise levels fall within manufacturer-specified ranges.
• Periodic calibration checks with reference standards are consistent with the system’s validated state.

Data Integrity Controls for Computerized Metal Detectors

Modern metal detectors used for tablets and capsules may be equipped with advanced control panels, electronic records, and connectivity with central control or Manufacturing Execution Systems (MES). OQ protocols should include thorough checks for data integrity controls, per ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available):

• User Roles and Access Control:
  • Verify that system access is password protected.
  • Roles should be defined (e.g., "Operator," "Supervisor," "Administrator") and tested for appropriate privilege levels.
  • Confirm only authorized users can change setpoints, calibrate, or perform data export.
• Audit Trail Functionality:
  • Challenge the system by making and documenting parameter changes. Confirm the audit trail logs all changes with user ID, date/time stamp, old/new values, and reason (where required).
• Date & Time Synchronization:
  • Check that system clocks match the official plant time (critical for traceability and regulatory compliance).
• Backup and Restore Testing:
  • Simulate a system failure. Confirm data can be restored from the most recent backup without loss or corruption.

GMP Controls During OQ Execution

Stringent GMP controls must be maintained and verified throughout OQ activities. These controls are critical not just to validation, but to day-to-day operation of the metal detector in production. Major checks include:

• Line Clearance:
  • Document that the area is cleared for the validation activity, with removal of all prior batch material and printed items.
• Status Labeling:
  • Place clear, accurate status labels (e.g., "Under Validation," "Qualified," "Out of Service") on the equipment.
• Logbook and Batch Record Integration:
  • Log every OQ activity, including challenge test outcomes, failures, corrective actions, instrument calibration verifications, and parameter changes.
  • Confirm that qualification outcome and routine checks are referenceable in batch records and electronic logs.

Safety and Compliance Feature Verification

The OQ must also assure that all environmental health and safety (EHS) features of the metal detector are fully functional and compliant with internal/external standards:

• Machine Guarding: Guards and covers over moving parts must be securely in place and interlocked so that removal halts operation immediately.
• Pressure Relief/Release Devices (if pneumatic): Verify that pressure regulators, relief valves, and safety releases operate as designed.
• Emergency Stop: All E-stop buttons within operator reach must be functionally tested for immediate isolation of power/motion.
• Electrical Safety: Confirm proper earthing, no exposed live parts, and clear labeling of all electrical enclosures.
• Lockout/Tagout Provisions: Demonstrate the ability to safely lock out power sources during maintenance or validation work.

Typical OQ Execution & Data Integrity Checklist for Metal Detectors

The table below highlights key verification points during Operational Qualification for a metal detector installed at the tablet/capsule stage. These examples are for illustration. Actual site requirements may vary:

The above OQ activities, data integrity checks, and GMP controls collectively ensure the metal detector is fit for its intended purpose on the oral solid dosage production line, mitigating risk to patient safety and reinforcing regulatory compliance.

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Performance Qualification (PQ) in Metal Detector Validation

Performance Qualification (PQ) for tablet and capsule stage metal detectors in oral solid dosage manufacturing is the critical phase that demonstrates consistent and reliable detection performance under actual production conditions. Robust PQ strategies ensure the metal detector can identify and correctly reject tablets or capsules contaminated with ferrous, non-ferrous, and stainless steel metal particles at defined sensitivities.

PQ Routine and Worst-Case Strategies

PQ should be executed in both routine and worst-case scenarios. Routine PQ verifies operational capability under standard operating conditions, typically with standard placebo or product runs. Worst-case PQ simulates challenging product characteristics (e.g. very large, dusty, high iron-content, or unusually shaped tablets), fast line speeds, and high-throughput conditions to demonstrate the detector’s robustness.

During PQ, test pieces of calibrated size and metal type (ferrous, non-ferrous, stainless steel) are introduced at various positions within the product stream (beginning, middle, end of batches), ensuring comprehensive verification of detection and rejection mechanisms. The PQ plan should also cover rejected and non-rejected events to assess the system’s reliability and susceptibility to false positives/negatives.

Sampling Plans, Repeatability, and Reproducibility

A statistically justified sampling plan for PQ ensures sufficient data for performance assessment. Typically, each metal type/test piece is passed through the detector multiple times (e.g., 10-20 repetitions per type/position), aiming to demonstrate repeatable and reproducible performance. If the detector unit is used on multiple products, PQ must include a representative matrix across all relevant product types, sizes, and packaging configurations.

PQ Acceptance Criteria

Acceptance criteria must be clearly defined and justified in the PQ protocol. Common acceptance criteria for metal detector validation include:

• 100% detection and automatic ejection of test pieces (no misses or false accepts)
• No false positives during passage of empty slugs/non-contaminated tablets
• Accurate triggering of alarms and proper documentation of each event
• Rejection of contaminated product without delay or blockage of product flow

Cleaning Validation and Cross-Contamination Controls

As tablet/capsule metal detectors typically have product-contact surfaces, cleaning validation and cross-contamination prevention are essential. PQ must confirm that after cleaning, detector performance is unaffected, and the surfaces do not retain residues or contribute contaminants to subsequent batches. A post-cleaning performance verification (challenge test) further demonstrates that detector sensitivity is uncompromised, linking cleaning validation with equipment performance and GMP compliance.

Continued Process Verification and Qualification

Following initial qualification, continued qualification (also known as continued process verification) assures long-term detector performance. This is typically implemented via:

• Routine challenge tests at defined intervals (e.g., start, middle, end of each production batch; after cleaning; after maintenance interventions)
• Trending of detection/rejection events and investigation of anomalies
• Documentation of all results and review by Quality Assurance

Systems should trigger periodic, risk-based requalification, particularly if significant equipment, product, or process changes occur.

SOPs, Training, Maintenance, Calibration, and Spares

Comprehensive, version-controlled Standard Operating Procedures (SOPs) are required for:

• Routine operation and monitoring
• PQ and challenge test execution
• Equipment cleaning
• Recording of deviations and out-of-specification events
• Maintenance and calibration procedures

Personnel involved in metal detector operation and maintenance must be demonstrably trained and qualified. Training records are needed for GMP compliance.

Preventive maintenance schedules—e.g., periodic checks, inspection of reject mechanisms, securing sensors—must be defined and adhered to. The calibration program requires regular verification and, if required, adjustment of detector sensitivity with certified test pieces. Ready availability of critical spares (sensors, rejection arms, electronics) minimizes downtime and ensures rapid resolution of failures.

Change Control, Deviations, and Requalification Triggers

All modifications to the metal detector equipment, software, product stream, or related SOPs must be subject to change control. This process evaluates the potential validation impact, necessitating partial or full requalification as justified by risk assessment.

Any deviations during PQ or routine use (e.g., missed detections, false positives, rejector jams, or failed challenge tests) are documented, investigated, and linked to the Corrective and Preventive Action (CAPA) system. Depending on investigation outcomes, actions may include retraining, maintenance, SOP updates, or equipment requalification.

Validation Deliverables and Documentation

Effective metal detector validation requires a formalized protocol and report structure that supports full traceability and regulatory scrutiny. Key documents include:

• PQ Protocol: Outlines objectives, test procedures, sampling plans, acceptance criteria, and responsibilities.
• PQ Report: Details execution (raw data, results, any deviations), final PQ outcome, and references to supporting documentation (calibration records, training).
• Summary Report: Provides a succinct validation statement, conclusions, and any outstanding issues.

Traceability matrices should link each user requirement and functional specification to the corresponding test, ensuring that all critical aspects are verified. All validation documents must be authorized, version-controlled, and readily retrievable for audit purposes.

Frequently Asked Questions (FAQ) about Metal Detector Validation

How often should PQ challenge tests be performed on metal detectors?

Industry best practices and regulatory expectations typically require challenge tests at the start, middle, and end of each production batch, after maintenance, and post-cleaning. Site SOPs should define the exact frequency based on risk assessment and product criticality.

What types of test pieces are required for metal detector PQ?

PQ should use certified test pieces representing ferrous, non-ferrous, and stainless steel materials, sized according to sensitivity specifications and the smallest contamination reliably detectable as agreed during qualification.

What should be done if the metal detector fails during production?

Production should be stopped, impacted product segregated, and an investigation initiated per deviation procedures. The failed detector must be serviced, recalibrated, and successfully challenged before resuming use. The event should be formalized in CAPA systems if warranted.

How is cleaning validation linked to metal detector PQ?

Cleaning validation ensures that detector surfaces do not contribute to cross-contamination. PQ after cleaning (post-cleaning verification) ensures cleaning does not affect sensitivity or performance, maintaining both product safety and detector functionality.

Do software changes to the detector require requalification?

Yes, all software or firmware changes must be assessed via change control. If the change could affect detection logic, sensitivity, data integrity, or alarm functions, partial or complete requalification is necessary.

Who can perform metal detector challenge tests?

Challenge tests must be performed by trained, authorized personnel who have demonstrated competence via documented GMP training. Details and requirements should be described in validated SOPs.

Is periodic calibration required for all metal detectors?

Yes, periodic calibration at intervals specified by the manufacturer and internal SOPs is required, with calibration records maintained for regulatory inspection. Calibration ensures continued accuracy and consistency of detection thresholds.

Conclusion

Effective metal detector validation at the tablet and capsule manufacturing stage is a cornerstone of contamination control and product quality assurance in oral solid dosage forms. PQ, when leveraged alongside rigorous cleaning verification, SOP adherence, and a robust training, maintenance, and documentation system, assures ongoing detector reliability and regulatory compliance. With proactive change management and a well-integrated CAPA approach, manufacturers can ensure sustained protection against metal contamination risks, preserving both patient safety and organizational reputation.