Buyer's Guide: Particle Counters

Why Particle Counting Matters to Your Operation

The problems you're solving:

Invisible airborne particles create visible problems. A single contamination event can:

• Trigger costly product recalls
• Fail regulatory audits (FDA, ISO, EU GMP)
• Compromise sensitive manufacturing processes
• Reduce HVAC system efficiency
• Create warranty claims and customer complaints

Particle counters quantify what you can't see, transforming "it looks clean" into documented proof of air quality.

Who Needs a Particle Counter?

You're a likely customer if you:

Cleanroom Operations

• Must maintain ISO 14644 classifications (Class 5, 6, 7, 8, or 9)
• Manufacture pharmaceuticals, medical devices, or semiconductors
• Need documented proof of contamination control for audits
• Perform routine cleanroom certification or monitoring

HVAC & Building Services

• Commission or balance cleanroom HVAC systems
• Verify filter performance and replacement schedules
• Investigate indoor air quality complaints
• Validate contamination control in critical areas

Quality Control & Manufacturing

• Monitor production environments for sensitive products
• Troubleshoot contamination issues in assembly areas
• Validate cleaning procedures and protocols
• Support root cause analysis for product defects

Facilities Management

• Maintain controlled environments in hospitals, labs, or data centers
• Document air quality for tenant compliance
• Optimize energy costs by avoiding unnecessary filter changes

3-Channel vs. 6-Channel: Which Do You Need?

The difference isn't just about more data—it's about diagnostic capability.

3-Channel Counters (typically 0.3, 0.5, 5.0 µm)

• Best for: Basic ISO classification and pass/fail monitoring
• What you get: Confirms your space meets minimum cleanliness standards
• Limitation: Can't differentiate particle size distribution patterns
• When it's enough: Routine monitoring of stable, proven processes

6-Channel Counters like the UT337B (0.3, 0.5, 1.0, 3.0, 5.0, 10.0 µm)

• Best for: Troubleshooting, trend analysis, and source identification
• What you get: Detailed particle size distribution reveals why counts are changing
• Key advantage: Distinguish between different contamination sources
  • Fine particles (0.3-0.5 µm): Combustion, skin cells, bacteria carriers
  • Medium particles (1.0-3.0 µm): Dust, pollen, mold spores
  • Large particles (5.0-10.0 µm): Fiber shedding, poor filtration, human activity
• When you need it:
  • Initial cleanroom commissioning
  • Investigating contamination events
  • Validating process changes
  • Supporting continuous improvement initiatives

The practical difference: When counts spike, a 3-channel counter tells you there's a problem. A 6-channel counter helps you identify the source—failed HEPA filter (if larger particles increase) vs. increased personnel activity (if smaller particles spike) vs. external infiltration (if pattern matches outdoor air).

Industry Standards & Compliance Requirements

Particle counters are required or referenced in:

ISO 14644 (International Cleanroom Standards)

• Defines cleanroom classifications (ISO Class 1-9)
• Mandates particle counting for classification and monitoring
• Specifies sampling volumes and reporting requirements
• Why it matters: Global standard for cleanroom certification; required for pharmaceutical, medical device, and electronics manufacturing

FDA 21 CFR Part 211 (Pharmaceutical Manufacturing)

• Requires environmental monitoring in controlled areas
• Mandates documentation of air quality in production zones
• Why it matters: Non-compliance can result in warning letters, production shutdowns, or FDA consent decrees

EU GMP Annex 1 (European Pharmaceutical Standards)

• Requires continuous or frequent monitoring of Grade A/B areas
• Defines particle count limits for different cleanroom grades
• Why it matters: Required for pharmaceutical products sold in European markets

USP <797> & <800> (Compounding Pharmacy Standards)

• Specifies air quality requirements for sterile compounding
• Requires routine environmental monitoring
• Why it matters: Protects patient safety in hospital and retail pharmacies

ISO 21501-4 (Particle Counter Calibration)

• Defines performance specifications for particle counters
• Establishes calibration requirements
• Why it matters: Ensures measurement accuracy and traceability

IEST-RP-CC006 (Testing Cleanrooms)

• Provides testing methodologies for cleanroom certification
• Defines sampling locations and protocols
• Why it matters: Industry best practice for cleanroom validation

Making the Right Choice

Choose a 3-channel counter when:

• You're performing routine pass/fail monitoring of an established process
• Budget is the primary constraint
• ISO classification verification is your only requirement
• You have proven procedures and stable conditions

Choose a 6-channel counter when:

• You're commissioning new cleanrooms or processes
• You need to investigate contamination sources
• You're responsible for continuous improvement
• Regulatory auditors expect detailed environmental data
• You support multiple areas with varying requirements

Why the UT337B 6-channel makes sense: At a price point comparable to many 3-channel instruments, the UT337B provides diagnostic capability that pays for itself in faster troubleshooting, reduced downtime, and more confident process control. You're not just buying compliance documentation—you're buying the ability to understand and improve your environment.

Key Features to Look For

Regardless of channel count, your particle counter should provide:

• Flow rate accuracy: Ensures reliable sampling (typically 2.83 LPM / 0.1 CFM)
• Battery operation: Enables portable monitoring throughout your facility
• Data logging: Documents trends and supports compliance reporting
• Environmental sensors: Temperature and humidity context for particle data
• User-friendly interface: Reduces training time and operator error
• Calibration certificate: Establishes measurement traceability

Bottom Line

Particle counters transform invisible risks into manageable data. Whether you're maintaining compliance, troubleshooting contamination, or optimizing your controlled environment, the right instrument helps you work smarter—not harder.

For operations requiring basic monitoring, a 3-channel counter provides essential compliance data. For teams responsible for process improvement, investigation, and detailed environmental control, a 6-channel counter like the UT337B delivers the diagnostic insight needed to maintain—and prove—world-class air quality.