THE SCIENCE BEHIND THE SEAT (SEAT SAFETY-PART TWO)

Fire-Resistant Cushioning Adding Safety to Bus Interiors

By Anthony Tomasello & Alicia Dixon

Safety is naturally a major concern when it comes to public transportation. Compliance to the Federal Motor Vehicle Safety Standards is often assumed to be sufficient in keeping passengers safe. But what if there is more that should be done, specifically with the threat of internal vehicle fires? Representatives from Chestnut Ridge Foam, Inc., a 30 year-old fire-resistant foam manufacturer in western Pennsylvania, discuss concerns with the absence of fire-resistant foam in bus transportation seating and the immediate solutions available in the industry.

Traditional polyurethane cushioning burns profusely, emitting tremendous volumes of thick, black, toxic smoke.
Traditional polyurethane cushioning burns profusely, emitting tremendous volumes of thick, black, toxic smoke.

1. Please explain the risks / liabilities associated with traditional FMVSS 302 seat cushioning.
One of the main contributors to interior fires on buses is the use of polyurethane cushioning, as it often represents the largest fuel load within the interior of the vehicle. Unfortunately, many individuals responsible for vehicle specifications mistakenly believe that FMVSS 302 seat cushioning provides a level of suitable fire protection. On the contrary, this traditional polyurethane cushioning will burn profusely, emitting tremendous volumes of thick, black, toxic smoke when exposed to a minimal open-flame ignition source. To add further alarm, an interior fire can spread rapidly, which is especially critical when considering the expanded use of public transportation by the elderly or those with restricted mobility. Eliminating this highly combustible item within the bus interior is a considerable step to best ensure passenger safety.

2. To what extent can fire-resistant cushioning minimize damage in a bus fire?
The use of fire resistant cushioning offers a multitude of benefits in the event of a bus fire. Not only can this fire-resistant foam prevent the ignition of a seat, but it also prevents the flames from rapidly spreading through the interior of the vehicle. As in any fire, adding valuable time reduces threat to life and allows passengers to safely evacuate the vehicle.

3. What tips on seat cushioning would you impart to bus owners / transit authorities who are purchasing buses?
Beyond the use of fire-resistant cushioning, take into account the covering material as well. A proper foam upholstery combination is needed to ensure the performance of the cushion. If the covering allows contaminates (dirt, liquids, and even UV light) to penetrate to the foam cushioning, it may have a negative impact on performance and compromise the longevity of the cushion. The proper construction of the cushion assembly should utilize upholstery with a smooth undersurface to provide synergy between the two materials. This is recommended to avoid abrasion created by covering with a rough, sandpaper-like backing. If a rough undersurface is used, a lightweight material such as muslin fabric is suggested between the cover and cushioning.

4. What safety-related questions should be asked when specifying seat cushions?  
Be sure to include performance-oriented criteria in the seating specifications. This will ensure that the FTA-suggested level of fire safety performance is being utilized. To support this, Chestnut Ridge Foam offers condensed specification verbiage which can easily be inserted into the seating section of new vehicle bid packages. Without the necessary language present, the foam will most likely default to flammable, polyurethane cushioning.

5. What effect does fire-resistant cushioning have on the bottom line?  
While we cannot put a dollar value on the safety of passengers, it is understood that cost and the bottom line are always a factor in any industry.  With durability in mind, Chestnut Ridge Foam has developed CR Safguard® XL and CR Safguard® XL60 to maximize service life. Utilizing this fire-resistant cushioning not only extends the life of a seat for a long-term cost benefit, but also maintains the proper and critical level of fire safety for passengers.

Anthony Tomasello and Alicia Dixon represent Chestnut Ridge Foam, Inc. in the Sales and Marketing division. For more information on how to make seats safer for passengers with fire resistant foam, please visit: www.chestnutridgefoam.com or call 800-234-2734 ext. 264.