Why in the News?

Air tankers have dropped thousands of litres of pink fire retardant (PFR) to slow the spread of wildfires in Los Angeles.

Pink Fire Retardant (PFR) and its properties

The PFR is a chemical mixture designed to slow or suppress wildfires by reducing the flammability of vegetation and other materials.
The most recognized brand of PFR is Phos-Chek, manufactured by Perimeter Solutions.
It is primarily made of ammonium phosphate-based slurry, including:
- Monoammonium phosphate (80%-90%).
- Diammonium phosphate.
- Performance additives for enhanced effectiveness.
- Pink dye for visibility.
It is sprayed as a foam or slurry to coat vegetation ahead of wildfires.
It slows combustion by:
- Depleting oxygen needed for flames.
- Altering how cellulose (plant material) decomposes, creating non-flammable carbon.
Unlike water, which evaporates quickly, PFR’s chemical components remain effective for days or weeks, providing long-term protection.

Provides fire-fighters with critical time to control wildfires.
Creates firebreaks by coating vegetation and preventing ignition.
Effective in diverse terrains, slopes, and weather conditions.
Helps protect natural habitats and human infrastructure by slowing wildfire spread.
Reduces the scale and intensity of wildfires, minimizing ecological damage.

[2019] Consider the following:

Which of the above are released into atmosphere due to the burning of crop/biomass residue?

(a) 1 and 2 only
(b) 2, 3 and 4 only
(c) 1 and 4 only
(d) 1, 2, 3 and 4