# How does the ±0.01 mm thickness tolerance improve reliability?

> Source: https://breathablefilm.com/news/knowledge-center/thickness-tolerance-precision-reliability/
> Author: kh_sales02
> Published: 2026-04-28
> Updated: 2026-08-28

## Key takeaways

- A ±0.01 mm thickness tolerance eliminates invisible "thin spots" that uneven casting can create, guaranteeing barrier integrity and tear resistance across the entire roll width.
- Because WVTR is directly affected by film thickness, this precision keeps breathability uniform across the film with no hot spots or variation for the end-user.
- This consistency also gives downstream manufacturers a predictable material that runs reliably on high-speed automated packaging or gown production lines.

## Frequently asked questions

### How does the ±0.01 mm thickness tolerance improve reliability?

A plus or minus 0.01 mm thickness tolerance eliminates the invisible thin spots that uneven casting can create, so the film has consistent barrier integrity and tear resistance across the entire roll width instead of hidden weak points. Because WVTR is directly tied to thickness, this precision also keeps breathability uniform across the film with no hot spots for the end-user, and it gives downstream manufacturers a consistent, predictable material that runs reliably on high-speed automated packaging or gown production lines.

### Why is WVTR directly affected by film thickness?

Water Vapor Transmission Rate depends on how far vapor molecules must travel and how uniform the pore structure is through the film's cross-section, so thickness variation changes that path and creates inconsistent breathability. Controlling thickness within a ±0.01 mm tolerance keeps WVTR uniform across the film, avoiding "hot spots" for the end-user.