Test methods

Test Methods

Texwipe has been the leader in contamination control products such as cleanroom wipers for over 40 years. From the outset, it became clear that in order to innovate to meet tighter tolerances, smaller feature sizes and lower contamination requirements and to supply the highest quality products on a consistent basis, testing our products to the strictest standards is paramount.

Some simple test procedures such as those for basis weight, absorbency and non-volatile extractables were available from standards organizations such as the American Society for Testing Materials (ASTM), the Association of the Nonwoven Fabrics Industry (INDA) and the Institute for Environmental Sciences and Technology (IEST) and could be modified easily for our use. Others, such as particle testing using Scanning Electron Microscopy (SEM) enumeration, ion testing with ion chromatography and the measurement of fabric surface resistivity required us to innovate and develop new methods that would be accurate and reproducible. We have been diligent in publishing this information in open literature and in making our test methods available to the standards organizations.

We trust that these test methods will be of value to you by providing the data needed to choose the optimum cleanroom for your requirements. Our intention, as always, is to help you to address contamination issues before they become insurmountable problems.

We welcome feedback on these methods. Please contact us with any questions or feedback.

Basis Weight

  • Determination of Basis Weight, Absorbency and Rate of Absorbency of Wipers -- Test Method 20 (TM20) - Knowledge of wiper basis weight is important since it allows the expression of other measurements in units of either weight or area.

Nonvolatile Residue (NVR) in Wipers and Other Material

  • Matter Extractable from Wipers and Other Materials -- Test Method 1 (TM1) - To determine the mass of material extractable from a wiper (or other item) using a given solvent.


  • The Determination of Ions in Wipers by Ion Chromatography (IC) -- Test Method 18 (TM18) - A rapid analytical technique for qualitative and quantitative determination of a wide variety of ionic species.

NVR Extractable from Swabs

  • Procedure for Determining the Nonvolatile Residue (NVR) Extractable from Swabs in a Given Solvent -- Test Method 10 (TM10) - Swabs are not only present in the cleanroom, but are normally used directly on the products being manufactured or in critical sampling procedures. One form of swab contamination is the soluble matter extractable in a given cleaning solvent (nonvolatile residue or NVR). NVR contamination can remain on a surface after cleaning with a wetted swab.

Particle Release from Wipers

  • Particle Release from Wipers and Other Materials Under Conditions of Moderate Mechanical Stress -- Test Method 22 (TM22) - This test method details the extraction and enumeration of particles and fibers released from wipers (or other materials) in a wetted state, under conditions of moderate mechanical stress.

Physical Properties of PVA

  • Physical Properties of Open-Cell Foam Roller Brushes -- Test Method 17 (TM17)  - Measures apparent density, effective porosity, absorption capacity and speed, pore size, 30% compression, tensile strength and elongation, and pH of PVA.

Surface Resistivity

  • The Determination of the Surface Resistivity of Fabrics and Other Thin, Flat Materials -- Test Method 14 (TM14)  -Wipers (dry) or garments can generate static charge due to contact with surfaces. Such charges can subsequently lead to electrostatic discharge (ESD) that can damage products or equipment or cause robotic equipment to malfunction (due to electromagnetic interference, EMI).

Swab Handle Resistance

  • Determination of the Resistance per Unit Length (ohm/cm) of Swab Handles -- Test Method 16 (TM16)  Swabs can transport charge and generate static charge due to contact with other surfaces. Such charges can subsequently lead to electrostatic discharge (ESD) that can damage products or equipment.