The Possible Link Between Cooking Fires and Subrogation Potential

Unattended cooking is the main ingredient in many residential cooking fires, according to the National Fire Protection Association (NFPA). Its latest “Home Cooking Fires” report identifies it as the top contributing factor to these incidents. 

However, appliance failures—stemming from improper range installation or manufacturing defects—can also spark fires and raise questions about subrogation potential. Learn more about these failure modes and how product failure testing can identify them. 

Unattended cooking leads to many, but not all, kitchen fire claims. Certified fire investigators should explore and rule out all potential causes before you reach any claim decisions. 

Installation Errors and Cooking Appliance Fires 

Range installation errors are typically confined to power cords or gas connectors, but their impact can be severe if not properly addressed. 

Improperly tightened screw terminals at an electric range’s power cord connection have been linked to fires. This seemingly minor oversight could lead to resistance heating, which can create the perfect conditions for a range fire to ignite. 

Gas ranges, on the other hand, are particularly vulnerable to damage at the gas connector. Abrasion against the back of the range housing can wear down the connector over time, creating holes and a gas leak looking for an ignition source.  

Another failure mode linked to an installation error is abrasion to the power cord. This can expose the energized conductors, which can then arc to the gas connector, causing a hole and an ignition source.  

Abrasion to the power cord of a gas range can expose energized conductors, leading to arcing to the gas connector. This arcing can create a hole in the gas connector, resulting in a gas leak that, if ignited, could trigger a fire. 

Onsite, certified fire investigators can examine all the elements of a fire scene and may recommend further testing if they determine that the most plausible origin and cause was related to an appliance.  

At this stage, Professional Engineers can conduct non-destructive or destructive testing to establish whether a range installation error contributed to the fire. Their findings provide valuable insights for making informed decisions about subrogation. Should a subrogation claim proceed to litigation, these experts can also serve as credible witnesses, strengthening the case with their technical expertise. 

Manufacturing Defects Observed in Cooking Appliances Post-Fire 

How an appliance was made before it ever entered the home could also impact its propensity to start a fire. Older electric ranges, and even some newer models, rely on electromechanical controls. These systems are generally robust, as they require multiple independent failures to cause a fire. However, the shift toward digital controls in modern electric ranges has introduced new vulnerabilities. 

Many newer electric ranges rely on digital controls, such as potentiometers or touchscreens, and relays in their circuit boards to manage heating elements. However, food debris can infiltrate a potentiometer, causing an internal short circuit—a failure mode that has already led to Consumer Product Safety Commission (CPSC) recalls. 

Professional Engineers specializing in product failure testing should be familiar with these recalls and broader failure trends. At the same time, they must maintain objectivity in their investigations to provide unbiased, actionable insights into the root cause of a failure. Damage may not always be linked to a recall even on the same type of equipment. 

This image, taken of a range sent to Component Testing Laboratories (CTL) for product failure testing, provides a close-up of food debris inside the potentiometer. This contamination can potentially cause an internal short circuit, leading to a fire. 

High-current circuit board designs in ranges can present additional risks. In these ranges, copper traces and relays on the circuit board carry the full current flowing to the heating elements. Manufacturing flaws, such as improper spacing of circuit board tracings or surface contamination, can lead to arcing. Loose or under-rated electrical connectors can also overheat, further increasing the risk of fire. 

Another failure mode in ranges tied to a manufacturer’s defect involves the integrated circuits responsible for monitoring potentiometer or touchscreen controls and managing relay operations. Programming errors within these circuits can inadvertently activate the heating elements. 

This type of failure can often resemble user error. To investigate, a certified fire investigator should conduct a detailed interview with the insured to gather background information on the appliance—such as whether there’s a history of the stove activating without being turned on—and determine when it was last used (i.e., was it in use at the time of the fire or immediately beforehand). If the insured reports not using the stove at the time of the fire, and the investigator may recommend additional testing. 

Fire investigators also examine the position of range controls. If the dial was in the “off” position and fire patterns indicate flames on the stovetop at that location, a malfunction or defect would be considered. If the switch is damaged by the fire to the point where its position cannot be determined, product failure analysis may be the best next step. 

At Component Testing Laboratories (CTL), part of Alpine Intel’s suite of services, Professional Engineers can take X-rays of the range’s control panels or heating element control switches to look for breaks in the wiring that may not be otherwise visible. X-rays are also valuable for determining the position of a control switch without opening the range, allowing for non-destructive testing when preferred by the carrier. This kind of analysis allows Professional Engineers to identify the cause of a range failure, giving carriers the insights needed to make informed decisions regarding subrogation. 

Cooking Fires Caused by User Error 

The “Home Cooking Fires” NFPA report found that unattended cooking was the leading factor in both cooking fires and related casualties. 

But homeowners and renters often make other potentially dangerous mistakes in the kitchen, like using the warming or broiler drawer to store combustible items. Cutting boards, cardboard boxes, or dishtowels left in either of these places can create a significant fire hazard. Keeping air fryers or any other combustibles on the cooktop can also lead to disaster if the burners or heating elements are accidentally activated. 

A cutting board made from combustible materials was stored in this broiler drawer and was one of the first materials ignited in a kitchen fire. 

While origin and cause investigation reports may not explicitly cite “user error,” certified fire investigators from National Fire Experts (NFE) can analyze witness statements and onsite evidence to determine the most plausible origin and cause of a cooking fire, such as a cutting board that was left in an activated broiler drawer. They also provide expert recommendations for next steps, which may include retaining and testing evidence for potential product failures. 

As part of Alpine Intel, NFE works seamlessly with CTL. Should you decide to pursue additional testing, CTL’s in-house transportation service, Loss Logistics, can safely collect and deliver evidence to its East or West location for storage and testing. This streamlined process ensures a single-line chain of custody is maintained, preserving the integrity of evidence for potential subrogation proceedings.  

Get expert insights into product failures that may have caused fire, water, or other property losses by submitting an assignment to CTL today. 

Alpine Intel’s content is meant to inform and educate readers using general terms and descriptions. They do not replace expert evaluations that determine facts and details related to each unique claim.