Procedure for measuring wind speed and volume and calculating ventilation frequency in clean rooms of pharmaceutical plants

Author:Jason Peng
Cleanroom Engineering Technology Manager of Deiiang Company.

Product R&D Manager of GDC Inc. Cleanroom Equipment Manufacturing Company.

Executive Director of Guangdong Cleanroom Industry Association of China.

Engaged in R&D of related products for 15 years, with rich relevant technical experience
2024-11-18 | Visits:

Clean Work Clothes

Specialized garments for dust-free and antistatic environments

ElectronicsPharmaceuticalsMicrobial EngineeringPrecision Instruments

Understanding Clean Work Clothes

Clean work clothes are specialized garments designed for industries requiring dust-free and antistatic environments. These include:

Electronics manufacturing
Optical instruments production
Pharmaceutical manufacturing
Microbial engineering facilities
Precision instruments workshops
Biotechnology laboratories
Semiconductor fabrication
Aerospace component assembly

Typically made from synthetic fiber fabrics woven with conductive yarn, these garments require specialized cleaning methods to maintain their critical properties.

Cleaning Frequency

Clean work clothes are typically washed at least once a week. In high-demand environments, daily cleaning may be required.

Material Composition

Primarily made of polyester or nylon fabrics with integrated conductive yarns for static control.

Professional Cleaning

Over 95% of cleanroom garments are professionally cleaned to ensure compliance with industry standards.

Specialized Cleaning Process

Proper cleaning is crucial for maintaining the integrity of clean work clothes. Standard washing methods can actually contaminate these specialized garments.

Critical Cleaning Requirements

All processes must occur in A CleanRoom with higher cleanliness than the work environment
Water must be filtered; solvents distilled and filtered with 0.2μm membrane
Initial wash with clean water to remove water-soluble contaminants
Final wash with distilled solvent to remove oily residues
Antistatic agents can be used in final rinse if dust-free
Clothing with buckles must be washed in buckled state
Drying in dedicated Clean air circulation system

Washing Temperature Guide

Material	Temperature Range	Maximum
Polyester	60-70°C	70°C
Nylon	50-55°C	60°C

Packaging Requirements

After drying, garments must be:

Folded in a dedicated Clean Room
Packaged in clean polyester or nylon bags
Double-layer packaging or vacuum sealing as required
Packaging materials must have antistatic properties

Pre-Cleaning Inspection

Before washing, garments must be inspected for:

ScratchesDamagesBuckle integrityOil stainsContaminants

Defective items must be repaired, replaced, or scrapped before cleaning.

Performance Testing Methods

Purification Performance Testing

ASTM-F-51 Method (Microscope)

Air passed through test clothes captures particles on filter membrane. Particles counted under 400x microscope.

Air volume: 28L/min

ASTM-F-51 Revised (Counting)

Sample placed on stand with metal mesh. Particle counter measures dust particles after contact suction.

Air volume: 28L/min

Helmke Drum Test

Sample placed in rotating drum (43cm×33cm) with internal blades. Particles measured with counter.

Rotation: 10 rpm

Vibration Method

Sample vibrated in chamber, particles measured with counter. Larger particles captured on filter.

Vibration: 150/min

Standard References: JIS-B-9923 (Japan), IES Standard RP-CC-003-87-T (USA), ISO/TC209 (International)

Antistatic Performance Testing

Based on GB/T12703-91 "Test Methods for Electrostatics of Textiles". Critical for microelectronics industries.

AFriction Charging Voltage Method

Sample rubbed with standard cloth (nylon/polypropylene) on rotating drum at 400rpm. Measures maximum voltage generated within 1 minute.

BCharge Surface Density Method

Sample rubbed with nylon standard cloth under specific conditions to evaluate charge distribution across the surface area.

Key Considerations

Professional Cleaning

Essential for maintaining garment integrity and cleanliness standards

Regular Testing

Critical to ensure ongoing performance of dust-free and antistatic properties

Proper Handling

Inspection, packaging and storage are as important as the cleaning process

Clean work clothes require specialized handling throughout their lifecycle to maintain the stringent requirements of sensitive manufacturing and research environments. Proper cleaning, testing and handling procedures are essential for contamination control.

Based on industry standards: ASTM F-51, JIS-B-9923, IES RP-CC-003-87-T, and GB/T12703-91