What happens when PPR pipes burn?
I often get the question: "What happens when PPR pipes burn?"
Sometimes it is hard to find propper answers that is a bit more than anecdotal...on ”uber” Google. It is an serious question as PPR pipes get used in buildings, people live and work in buildings...and sometimes life happens.
Thankfully LyondellBasell supplies the PPR to Blue Ocean Industrial Development (UK) Group. Their technical manual puts it fairly concise:
“Polypropylene without fire retardant modification is rated as a class B2 (normally ignitable) construction material under DIN 4102 part 1 (Fire behavior of construction materials and construction components). It receives an HB fire classification under UL 94. At temperatures above 300°C, gradual thermal degradation of the molten polypropylene occurs, which gives rise to combustible gases. Polypropylene ignites on contact with flame and burns with a faintly luminous flame without significant smoke development, even after removal of the ignition source. The molten polymer can deposit burning drips. According to ASTM D1929-77, the spontaneous ignition temperature of polypropylene is 360°C and the flash ignition temperature is 330°C. With a sufficient air supply, the main combustion products of polypropylene are carbon dioxide and water, the natural constituents of air. If there is an insufficient air supply, carbon monoxide (CO) is formed as well as small traces of many different organic compounds. Among these, however, there are no substances that would increase the toxicity of normal fire gases. Even in the case of incomplete combustion, the thermal decomposition products are less toxic than those formed from wood under the same conditions. The fire gases have no special corrosivity. The oxygen index of polypropylene without flame retardant modification is approx. 18% (tested as per ASTM D2863 / ISO 4589). The calorific value of polypropylene and polyethylene is 46 MJ/kg or 12.8 kWh/kg. Their energy content is therefore about the same as that of fuel oil.” 1
So...it is less toxic than the fire from your braai wood...but please, do not try this at home or anywhere else.
PHOTO: Toronto Public Library. Some rights reserved.
