Parkiing garage fire sprinkler design density criteria

PARKIING GARAGE FIRE SPRINKLER DESIGN DENSITY CRITERIA CODE

Modern parking garages have optimized space requirements for vehicle parking and storage, and often implement automated retrieval features and car stacking, which presents unique hazards as well. Compared to older cars, modern cars burn differently.

As alternative fuel vehicles are popularized, concerns regarding their unique hazards, burn characteristics and typical burn duration have been raised. Some feel that the safer, more conservative route (lacking full-scale fire test data) is to change the occupancy to Extra Hazard Group 2 to ensure adequate protection rather than the complete removal of any design guidance.Р”Р„s previously stated, modern vehicles present new hazards, due to the incorporation of larger quantities of combustible materials (e.g., fuels, plastics, synthetic materials, etc.) intoР’В their designs. So it makes sense to classify parking garages similarly - especially as the cars themselves are now a more significant hazard than initially anticipated. Car stackers most closely resemble a lot of the modern parking garages, especially automated ones, and they are classified as Extra Hazard Group 2.

PARKIING GARAGE FIRE SPRINKLER DESIGN DENSITY CRITERIA CODE

The reason for the last proposed code revision is a combination of the first two. But with many, especially the ones outside the United States, parking garages often are not sprinklered. There have been many parking garage fires over the years and those fires have caused a lot of damage, so at first glance, it looks like a lack of adequate sprinkler protection is the issue. The concern here comes from the extensive shielding effect that occurs from having a car fire (one that presumably starts in the interior or under the hood of the car) with two additional cars in between the fire and a sprinkler, thus making it nearly impossible to РІР‚Сљput the wet stuff on the red stuff.РІР‚СњР”Р„dditionally, garage structures tend to be extremely inaccessible by fire apparatus, so getting water on the fires without a means already in the garage (sprinkler or standpipes) is extremely difficult. The proximity and configuration also play a role in the reason for including additional sidewall sprinkler protection for car stackers consisting of three or more cars. Not to mention the configuration and proximity of the cars measuring typically one to two feet apart, which promotes fire spread. Automobile design has continuously been evolving since cars were invented, and now modern vehicles contain significantly more plastic.Р”Р„dditionally, hybrid/electric drive cars pose a differentР’В risk with lithium-ion batteries that have the potential for thermal runaway and can burn for days. The reason for deleting parking garages from the Ordinary Hazard Group 1 stems from the concern that it is an inadequate hazard classification for such fires. The third and final suggestion ties into the first and proposes reclassifying the automobile parking occupancy from Ordinary Hazard Group 1 to Extra Hazard Group 2.

The second is adding sidewall sprinkler protection to car stackers of three or more cars to the Extra Hazard Group 2 occupancy list in NFPA 13 Section A.4.3.6. The first being the removal of automobile parking from the Ordinary Hazard Group 1 occupancy list in NFPA 13 Section A.4.3.3.1. Those fires sparked three code change proposals. These code changes stem from a growing concern regarding adequate fire protection in parking garages due to the seemingly unusually large string of recent parking garage fire losses. There are a few potential code changes underway regarding fire protection for vehicles in various parking arrangements for the latest edition (2022) of NFPA 13.

Parkiing garage fire sprinkler design density criteria