The Truth About Headlamp Burn Times
May 8 2024
Backpacking and trekking
When comparing the specs of Petzl headlamps with those of different brands, you’ll notice that Petzl’s max brightness burn times are usually 2-3 hours, while other brands claim to be in the 3-6 hour range or even more. Are the other brands using bigger batteries? Are they only highlighting the burn times of lower brightness settings? Are they using different standards to measure and report their burn times? Or are they programming their headlamps to provide more burn time resulting in a faster reduction in brightness? Let's dive into it.
Different batteries being used
Battery size and type can definitely play a role in how long your headlamp will operate and the level of brightness it will maintain. When you compare a 300 lumen Petzl headlamp with another 300 lumen headlamp and see a discrepancy in their burn times, look at what size of battery each one is using. If the headlamp with the higher stated burn time is using a bigger battery, that could also mean that it’s heavier. Is the theoretical extra burn time worth the extra weight, bulkiness, or imbalance on the head? Petzl doesn’t always use the biggest batteries. Instead, we focus on providing an ideal balance between performance and comfort, allowing you to carry the weight of additional batteries on your body rather than keeping all of the weight on your head.
Different brightness settings being used
Most headlamps have multiple brightness settings and each setting has a respective burn time. Some brands like to tout the more impressive numbers and display their “max burn time” right next to the “max brightness” info. This confuses the consumer into thinking that those two numbers coincide together when in fact the max burn time number correlates with the lowest brightness setting and the max power number is tied to its shortest burn time. Have you ever been duped into believing that a 500 lumen headlamp will last for 30 hours on the highest setting? On the website and on the packaging, Petzl makes it clear as to what kind of burn times you get with each brightness level.
Different standards being used
When companies use the same standards for measuring and communicating, headlamp performance is more comparable for consumers. Headlamp companies are not required to follow any standard regarding performance specifications but they do have the option to adopt the ANSI/PLATO FL 1 Standard. This standard—established in 2009, revised in 2016, and adopted by many of the major brands in 2019—defines burn time as the length of time “optimal light” is projected from the lamp. Its method of measurement starts 30 seconds after the headlamp is turned on, using new batteries, and ends when the brightness dims down to 10% of what it was 30 seconds after the light was turned on. Without adopting this standard, companies can measure their burn times from the first moment the lamp turns on to when it finally reaches 0% brightness. Did you ever consider that brands could be measuring the performance of their headlamps differently? Petzl uses the ANSI/PLATO FL 1 Standard because it holds us accountable in being clear and honest in our methods and communication tactics. Additionally, Petzl communicates the length of time the headlamp will operate in “reserve mode”—when the brightness of the lamp is 10% and below.
Different programming being used
Headlamps can be programmed to achieve performance specifications based on what the company wants to deliver. Some brands use this to look impressive with a high initial brightness that progressively dims to also offer a longer burn time. Other brands choose to prioritize consistent brightness by programming their lamps to use more battery power to hold a steady level of brightness for most of the burn time. Beyond that, there’s even technology out there that allows the lamp to automatically fluctuate its brightness to extend its burn time. Do you know in which ways each brand is programming their lamps? Most Petzl headlamps are programmed to retain at least 50% of its original brightness halfway through the burn time, instead of dimming down to 20-30%. Petzl also makes some headlamps with REACTIVE LIGHTING, analyzing the surrounding ambient light and automatically adjusting brightness to conserve battery power.
In the end, not all headlamps are created equal and each company has its own agenda. Petzl’s agenda is to provide reliable performance and a comfortable fit. When you buy a Petzl headlamp for an activity that specifically needs a certain amount of light, rest assured that it will give you as much of that brightness as possible, despite its shorter burn time.