What is the most common cause of orange flashes in a flame?

The most common cause of orange flashes in a flame is typically associated with the presence of dust or dirt in the combustion area. When dust or other particulates interrupt the combustion process, they can result in incomplete combustion, which produces flickering and a distinctive orange or yellow color in the flame. This color change occurs as the carbon particulates get heated and emit light at a lower temperature, leading to the visible orange hue.

In a well-functioning combustion system, flames should ideally appear steady and blue, indicating complete combustion with sufficient oxygen to burn the gas completely. The presence of impurities, such as dust, disrupts this ideal scenario, altering the flame’s characteristics and leading to the unwanted coloration.