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What is the difference between a 4-hour fire-rated door and a 6-hour fire-rated door?

The primary difference between a 4-hour fire-rated door and a 6-hour fire-rated door lies in their respective fire resistance ratings and their ability to withstand exposure to fire for a designated period of time. Let’s break down the key distinctions:

Fire Resistance Rating

  • 4-hour fire-rated door A 4-hour fire-rated door is designed to resist the spread of fire and smoke for up to 4 hours. This means the door has been tested and certified to maintain its structural integrity and prevent the passage of fire and smoke for a duration of 4 hours under controlled fire conditions.
  • 6-hour fire-rated door A 6-hour fire-rated door is designed to provide even higher fire resistance. It can withstand exposure to fire and smoke for up to 6 hours before losing its integrity and allowing the passage of fire and smoke.

Application and Use

Fire-rated doors are typically used in specific areas of buildings where fire protection is crucial. Both 4-hour and 6-hour fire-rated doors are employed in critical areas such as stairwells, elevator shafts, mechanical rooms, and other places that require extended fire resistance.

Stringency and Testing

Generally, a higher fire resistance rating indicates a more stringent and demanding set of testing conditions. To achieve a 6-hour rating, a door must undergo more rigorous testing than a 4-hour door, demonstrating its ability to withstand fire and heat for a longer duration.

Cost and Complexity

Due to the increased level of fire resistance required and the more intensive testing involved, 6-hour fire-rated doors are likely to be more expensive and complex to manufacture compared to 4-hour fire-rated doors.

It’s worth noting that fire resistance ratings beyond 3 hours (180 minutes) are less common because many building codes and fire safety standards tend to focus on shorter durations. The choice between a 4-hour and a 6-hour fire-rated door would depend on factors such as the building’s specific fire safety needs, local regulations, and the level of fire protection desired.

As with any fire-rated door, it’s crucial to work with professionals like FIRELOCK® in the Lehigh Valley, who have expertise in fire protection and building codes to determine the appropriate fire-rated doors for your building’s requirements.

Firelock manufactures fire-rated doors that comply with a 1-hour, 2-hour, 4-hour, and 6-hour UL Rated Class 350 rating. Getting a quote for your project is easy—simply click here and fill out the form.

About Firelock

Since 1982, FIRELOCK® has been the world’s leading manufacturer of media-rated modular vault chambers. Unlike poured-in-place concrete vaults, FIRELOCK® vaults are constructed from individual panels, filled with a heat-resistant ceramic material, and they are lightweight, movable, and expandable. When combined with current high-density storage systems, FIRELOCK® vaults offer extremely high space efficiency at a considerable cost advantage per cubic foot of storage. The value of assets stored in FIRELOCK® vaults today reaches hundreds of billions of dollars and ranges from priceless animation cells and World Wrestling Entertainment videos to pharmaceutical research records and U.S. Department of Education student loan information.

With a FIRELOCK® vault, you invest in the highest-performing vault on the market today to ensure the protection of your most vital records and irreplaceable items. You gain the ability to store microfilm, computer media, file servers, and paper in one location, as well as the peace of mind that comes from knowing that all the environmental- and fire-protection elements are in place.

FIRELOCK® has been in business since 1982, and during that time we have installed over 2000 vaults around the world. Because of this broad experience, we know how to build a vault that will provide you with maximum protection today and will have the flexibility to grow with you over time.