Fire Safety and Technology Editorial

 

Garbage can fires and cigarettes

Most US states are either requiring that cigarettes be "low ignition propensity cigarettes" (also, incorrectly, known as "fire safe cigarettes") or have legislation in place or pending that will eventually require the exclusive sale of such cigarettes. This has been discussed often in FS&TB. These cigarettes are also known by the abbreviations FSC (which stands for "Fire Standards Compliant" and not fire safe cigarette) or RIP (which stands for Reduced Ignition Propensity). These cigarettes comply with ASTM E 2187, a test that assesses the ignition power of cigarettes on cellulosic materials. The test uses filter paper but that is an excellent surrogate for cellulosic fabrics such as cotton. Traditional cigarettes have tended to ignite cellulosic fabrics almost every time they fell on these fabrics. Cigarettes complying with ASTM E 2187 are required to ignite the substrate not more than 25% of the time. That is a massive improvement but it does not mean that ignition won't happen: it happens but much less frequently.

The first US state that introduced regulation for RIP cigarettes was New York, which has required them since 2004. Recent statistics from New York State show the smokers' materials (mostly cigarettes) fire deaths in the state each year, for 1997 through 2008. In the years before the regulation, there were an average of 42.0 fire deaths while in the years since regulation, the yearly average went down to 28.5 fire deaths, a decrease of 32%. Even if we take into account that the number of adult smokers in New York State decreased by 19% from 2002 to 2007, the effect of RIP cigarettes is clearly welcome.

Having said that, recently studies have been conducted by fire fighters and they all found conclusive evidence that RIP cigarettes are still a potential fire hazard. The key area which needs to be investigated and where action is needed is in garbage cans. The experience of firefighters is that dumping cigarette ashes and/or butts into garbage cans is one of the most frequent causes of house fires. In a recent Albany GA study, firefighters ran two tests and in each one they set up a chair and couch in a condemned house, and placed an RIP cigarette in a garbage can containing newspapers and other trash. The cigarette smoldered for a few minutes, but, within five minutes the garbage can had a significant fire. Moreover, within 12 minutes, the fire had ignited both the chair and the couch next to it. Other experiments have been conducted by a group of fire investigators/firefighters and, although they found less dramatic results, they also found that the RIP cigarettes could get the garbage can to start a flaming fire. A fire/code official from Oregon has been tracking cigarette related fires for some time and has concluded that any time a cigarette ends up in a plastic garbage can the potential exists for a major fire.

The issue of igniting garbage cans is a particularly severe problem. Most traditional garbage cans are made of non fire retarded polyethylene and they release massive amounts of heat very rapidly. An experiment I conducted personally a number of years ago showed me that flashover in a standard room followed from igniting one standard garbage can. In the test a 30 gallon (114 Liter) garbage can, weighing roughly 22 pounds (10 kg) was filled with some household waste and ignited with a cigarette. The resulting fire was extinguished when the heat release rate exceeded 1 MW and the total heat released exceeded 200 MJ. At that time almost half of the garbage can was still unburnt!

Both the Uniform Fire Code (NFPA 1) and the International Fire Code (IFC) contain a number of requirements for large garbage cans. Both codes require large garbage cans constructed of combustible materials to be made of materials that comply with a peak heat release rate of not more than 300 kW/m2 when tested in the cone calorimeter (ASTM E 1354) when tested at an incident heat flux of 50 kW/m2 in the horizontal orientation. The cutoff came from a fire hazard analysis that looked at the heat release rate needed to ensure that no severe problem would result if a big garbage can (or laundry cart, actually) were to catch fire inside a hospital. The IFC/UFC requirements have resulted in research by major manufacturers who now have formulations available that can meet the fire safety criteria. Unfortunately, these particular fire code requirements are often not enforced, and some manufacturers have decided not to implement their new formulations until the code requirements are being enforced.

In summary, RIP cigarettes are a great step forward but they are still a potential source of fire and need to be kept far away from combustible garbage cans.


Marcelo M. Hirschler