Cleanroom Wiper Selection Fundamentals: Substrates and Edge Treatments

A documented cleanroom wiper specification process is critical to achieving high cleaning efficacy and avoiding product cross-contamination in your controlled environment.

[Part 2 in our Cleanroom Wiper Selection Fundamentals Series]

What Are Your Internal Cleanliness Specifications?

Selecting wipers should be based on your standard operating procedures and the cleanliness level needed based on the range of applications, from less critical facility cleaning to critical product contact processes.

The two main components of a wiper, the substrate and edge treatment, determine the absorbency, capacity, and cleanliness level. Each substrate has particles and extractables inherent in the material, and how the edges are finished or sealed also affects the cleanliness level.

Specify the Right Wiper Substrate Based on Performance Characteristics and SOP

Beyond the criteria of absorbency and level of cleanliness, each substrate has durability, chemical, and heat resistance performance characteristics that are important to understand.

The wiper you choose for general facility cleaning will require very different performance characteristics than the cleanroom wiper you specify for product cleaning or other critical product applications. Your SOPs for each process will help the cleanroom operators determine which wiper to use.      

The Edge Treatments Affect The Level of Cleanliness

Wipers made from the same substrate can have very different cleanliness levels and particle counts depending on how the edge is finished. After the wiper substrate is knife-cut into the appropriate size, additional edge treatments may be applied to seal the edges reducing particle counts of the finished wiper.

Edge treatments include laser seal, ultrasonic seal, and pressure heat seal. The cleanest edge treatment is the pressure heat seal because the edge is finished using heat and pressure to form the border of the wiper before being ultrasonically sealed.

 Download Now: Cleanroom Wiper Selection Guide

Custom Solutions to Clean Any Surface In Your Controlled Environment

Valutek has decades of experience manufacturing cleanroom consumables and we have developed the capabilities to produce wipers that meet any requirement.

We can manufacture any size of wiper for a wide range of applications with any edge treatment. If your facility also needs wipers that are pre-saturated with a cleaning solution, we can customize the chemical solution based on the application requirements and SOP. 

Trust But Verify

Once you have narrowed down the selection based on these characteristics, the next step is to ask for product quality test data from the manufacturer and verify with your independent testing. Valutek wiper absorbency, particle levels, and extractables are measured using repeatable tests performed according to IEST standards.

To test particle level, the Helmke drum test agitates the wiper to release the particles, and chemical analysis of the particles identifies the extractables.

If you don’t have the test equipment to verify performance, Valutek offers independent testing, even on other manufacturer products. 

To further your knowledge on cleanroom wipes, we suggest exploring the relevant materials:

• Valutek Cleanliness Classification
• Why Wiper Basis Weight Matters: Understanding Wiper Absorbency
• Cleanroom Wiper Cleanliness Criteria: Particle Count and Extractables
• What is a Wiper's Sorbent Capacity?
• Non-Compliant Cleanroom Packaging: A Recipe for Contamination Control
• Valutek Pre-wetted Wipers: Customizable Solutions for Your Cleanroom Needs