Figure 5
The illustration consists of two main sections, labeled “a” and “b,” arranged side-by-side. Section “a,” on the left, is a photo of a rectangular hotbox. The box is horizontally oriented and appears to be a robust, industrial-looking apparatus. Its front face is visible, showing several protruding elements, with some wires attached. A white, fibrous material is noted on top of the box. Section “b,” on the right, is a line graph. The vertical axis is labeled “Temperature (degrees Celsius),” ranging from 0 to 1000 in increments of 200. The horizontal axis is labeled “Time (minutes),” ranging from 0 to 60 in increments of 10. The graph displays five distinct curves with a common origin point. A gray curve, positioned highest, is labeled “I S O 834.” This curve begins at (0, 0), rises as a concave-down profile, and ends at (60, 900). Below it, a blue curve labeled “600 degrees Celsius” shows the temperature reaching and stabilizing around 600 degrees Celsius. An orange curve labeled “400 degrees Celsius” similarly shows stabilization around 400 degrees Celsius. The lowest colored curve, in red, labeled “200 degrees Celsius,” stabilizes around 200 degrees Celsius. Note: All the numerical data values are estimated.Heating test setup (a) hotbox and (b) heating temperature curves in the hotbox compared to the ISO 834 curve. Authors’ own work