Built to Protect: Enhancing Fire Performance

At Johns Manville, fire performance is about more than meeting standards—it’s about protecting people and creating safer, more sustainable buildings.

In our Fire Testing Lab, the tunnel test plays a vital role. This test measures how materials respond in the event of a fire—helping us evaluate flame spread, smoke development, and overall performance under extreme conditions. These insights ensure our products provide the time needed for safe evacuation and long-term reliability.

Here’s how it works:

1. Samples (about 2 feet wide by 24 feet long) are placed in the tunnel.
2. Air currents and a gas flame simulate fire conditions.
3. We track how quickly the flame spreads (the Flame Spread Index).
4. A laser sensor measures smoke levels (the Smoke-Developed Index).

Together, these measurements determine whether materials like fiberglass, polyiso foam, spray foam, and facers meet the Class A fire standard—helping ensure safety when it matters most.

Watch the video to see how JM is Enhancing Fire Performance in our products.