Being in the fire protection and life safety industry, I’ve heard my fair share of myths when it comes to different aspects of fire protection and life safety. The public often has misconceptions of how sprinkler systems or fire alarm systems operate based on what they see in movies or on television. But I’ve also heard those within the industry perpetuate myths. One reason for this is that the fire protection and life safety industry is so large and covers many different topical areas.

By Shawn Mahoney 

This blog lists the top five myths—and the truth behind them—that I and the other members of the Technical Services group at NFPA® have heard throughout our careers.

Myth 1: Hazardous Materials Are Always Obvious

Many people think that a hazardous material is going to be obvious when they see it. They think about the glowing green liquids that you see in movies or TV shows, but in reality there are many materials that can be hazardous while having no physical characteristics that can be used to identify them as hazardous.

Fact: Hazardous Materials Are Not Always Obvious

NFPA 400, Hazardous Materials Code, breaks down materials as being either a health hazard or a physical hazard. Health hazard materials can be toxic, highly toxic, or corrosive, while physical hazard materials can be explosive, flammable, an oxidizer, or an unstable material. Materials with these hazards may not present themselves with a physical characteristic. Check out this blog from my colleague Val Ziavras to learn more about what a hazardous material is.

Since a hazardous material is not always obvious, it is important to provide visible hazard identification signs for both building occupants and first responders. NFPA 704, Standard System for the Identification of the Hazards of Materials for Emergency Response, can be used to create those placards which identify the health, flammability, instability, and special hazards of materials. A quick reference to the 704 identification system can be seen below and this blog by Jon Hart goes into much more detail on the identification system.

Myth 2: Chocking a Door Open Is Not Dangerous

Many people may think that propping open a self-closing door like seen in the image below is an innocent action. However, if the door that is propped open is a fire door, then this action is risking the lives of the occupants as well as the integrity of the building if a fire were to occur. This is because a fire door is an assembly that is installed in a fire wall or fire barrier to provide a degree of fire protection to that opening.

Fact: Chocking a Door Open Is Dangerous

If a fire door is not able to self-close and latch, then it is unable to properly protect the opening in the fire wall or barrier that it is protecting. This will lead to fire being able to spread uncontrolled throughout a building and, most importantly, into areas such as hazardous locations or into protected areas such as an exit stairwell that occupants rely on to evacuate the building during a fire. Below is a side-by-side image showing the two opposite sides of a fire door that was able to prevent a fire from spreading into the next compartment. This would not have been possible if the door had been propped open. Learn more about the critical role fire doors and fire barriers play in safety in this blog.

Myth 3: Electric Vehicles Burn Hotter than Internal Combustion Engine Vehicles

As the world begins the switch to using more electric vehicles (EVs) for transportation, we have begun to see fires involving EVs. One of the myths that we hear is that EVs burn hotter than a typical internal combustion engine (ICE) vehicle.

Fact: Electric Vehicles Do Not Burn Hotter than Internal Combustion Engine Vehicles

Research by the Fire Protection Research Foundation as well as a recent report published in the journal Fire Technology found that, overall, EVs do not present a greater hazard than ICE vehicles. It was found that ICE vehicles have a larger peak heat release rate (HRR) due to the burning of the fuel in the gas tank, but it burns out quickly. EV fires tend to develop slower and not get as large, but they burn for much longer. Additionally, many of the other components of a vehicle such as the plastic interior and body pieces are the same between an EV and an ICE vehicle so those components will burn similarly.

It is important to note that the lithium-ion (or similar) batteries inside of EVs fail and burn in a much different way than internal combustion engine (ICE) vehicles. When lithium-ion batteries fail, they go through a process called thermal runaway, where a single cell failure can cause the production of heat and oxygen as well as flammable and toxic gasses. This then spreads to adjacent cells causing potential rapid fire growth or explosions. That, in addition to the other unique characteristics of an EV fire such as stranded energy and reignition, make the firefighting response to an EV fire much more complicated than an ICE vehicle fire. To learn more about training resources from NFPA on EV hazards, check out this webpage.

Myth 4: Smoke Alarms in a Hotel or Apartment Will Set Off the Entire Building Alarm

Many people think that all of the building fire alarm system notification appliances will initiate if they were to accidentally set off the smoke alarm within their apartment or hotel, when in reality NFPA 101®, Life Safety Code®, would not permit that to happen.

Fact: Smoke Alarms in a Hotel or Apartment Will Not Set Off the Entire Building Alarm

Section 9.6.2.10.11 of the 2021 edition of  NFPA 101 requires that dwelling unit smoke alarms only sound within that individual dwelling unit and not within the entire building. The reason behind this is that if there were an accidental activation of these alarms within a unit the entire building would not need to evacuate.

However, if a smoke detector within a common space of the building or water flow alarm from the sprinkler system where to activate then the entire building would be notified to evacuate since the water flow from a sprinkler is less likely to be an accidental activation, and the spread of smoke into a corridor or common space would impact occupants ability to escape. In some cases, fire alarm systems are designed so that a smoke alarm within one of the units or rooms will send a signal to a constantly attended location like a security desk so someone can investigate.

Myth 5: Firefighters Are Able to Easily See and Communicate Inside a Building on Fire

It goes without saying that movies and television shows don’t necessarily depict exactly how something happens in real life, and that is certainly the case when it comes to depicting the conditions inside of a structural fire. Sometimes, for instance, TV shows and movies will depict that firefighters can easily see and communicate with each other when they’re inside a structure fire but that is not the reality.

Fact: Firefighters Are Not Able to Easily See and Communicate Inside a Building on Fire

Fires within a structure can reach temperatures up to 1,100 OF (590 OC) and create smoke that can significantly reduce and even eliminate any visibility within the structure. Visibility is such a concern inside fires that NASA is working on location tracking services for firefighters should they themselves have an emergency and need to be rescued.

Because of this, NFPA 1001, Standard for Fire Fighter Professional Qualifications (being consolidated into NFPA 1010), requires that firefighters be able to perform all of their interior operations like search and rescue under obscured vision conditions.

 

SOURCE: NFPA