Extreme Heat, UV, Rain, Dust: One Material Passes Every Test for LED Sealing

When a U.S.-based LED manufacturer set out to design lighting fixtures for warehouses, hazardous locations, and fully exposed outdoor environments, they knew the housing had to do more than protect the electronics. It had to survive everything from arctic cold to desert heat, driving rain to fine dust — and do it for up to 10 years without a single leak.

The challenge wasn't just finding a gasket. It was finding a gasket that would not quietly fail over time, taking the entire fixture's reputation with it.

The Challenge: Heat, Time, and the Cost of a Small Part

At first glance, an LED housing seal seems like a minor component. But in this application, it sat at the intersection of several demanding conditions:

• Ambient temperatures from -40°F to +150°F — and even higher internally due to heat generated by the LEDs and driver electronics.
• Continuous exposure to UV radiation, rain, snow, humidity, and airborne dust in industrial and hazardous-area settings.
• A required service life of 5–10 years, backed by a 5-year warranty.

That last point was the real sticking point. Many gasket materials can seal effectively on day one. Far fewer can do so after five or ten years of thermal cycling, UV exposure, and compressive loading without hardening, cracking, or taking a permanent set.

The manufacturer's core concern was straightforward: "Will this material still be sealing in year seven?"

The Search: Data Over Guesswork

Rather than testing random off-the-shelf gaskets, the project team focused on materials with proven performance in extreme environments. They needed a material that would not only meet the temperature range on paper but also resist compression set — the tendency of a gasket to lose its ability to rebound after being squeezed for long periods.

That search led to BISCO® HT-800 medium-density silicone foam, supplied by Marian and supported by Deson, a Rogers preferred converter.

The Solution: A Material That Outperforms the Requirement

BISCO HT-800 was selected because its performance envelope comfortably exceeded the application demands:

The material's wide temperature margin was especially important. By choosing a foam rated to +392°F when the environment only reached +150°F ambient, the design team built in a safety buffer against internal heat buildup and long-term thermal degradation.

Equally critical was the die-cutting process. Deson precision-cut the foam to match the exact housing geometry, ensuring consistent compression around the entire perimeter of the fixture. No gaps. No thin spots. No over-compressed zones that would fail early.

Proven Results: Testing That Mirrors Real Life

The manufacturer built prototypes using the die-cut BISCO HT-800 gaskets and subjected them to accelerated life testing. The seals passed:

• IP64 — protected against dust ingress and water splashes from any direction, meeting the needs of outdoor and industrial environments.
• UL 94 V-0 — confirming the material would not contribute to flame spread in hazardous-area applications.

More importantly, the material’s compression set characteristics gave the engineering team confidence that the seal would still be performing when the 5-year warranty expired — and likely well beyond.

Beyond the Material: Supply Chain Confidence

A great gasket material is only as good as the partner who can deliver it consistently. Here, Deson played a role beyond simple material supply.

As a Rogers preferred converter, Deson maintains inventory of BISCO HT-800 and offers:

• Rapid prototyping and sampling — so design iterations don't stall the project.
• Custom converting capabilities — including adhesive lamination and hole punching to match any housing design.
• Reliable lead times — helping the manufacturer meet production schedules without last-minute surprises.

This meant the LED maker didn't just get a specification sheet. They got a repeatable, scalable supply solution that de-risked the entire product launch.

The Takeaway

Outdoor and hazardous-area LED fixtures live or die by the reliability of their seals. A few cents' worth of gasket material can determine whether a $500 fixture survives a decade of punishing conditions or fails within two years.

In this case, the answer was not a more complex housing or a heavier mechanical clamp. It was a smarter material choice — BISCO HT-800 silicone foam, precision-converted by Deson to meet exact housing tolerances.

The result: a seal that stays soft, stays tight, and stays certified — year after year.