Long-term fire retardant with corrosion inhibitors and methods for making and using same

A forest fire retardant concentrate, comprising:

• a retardant compound comprising at least one of monoammonium phosphate, monoammonium orthophosphate, monosodium phosphate, sodium ammonium phosphate, or sodium ammonium phosphate hydrate;
• a corrosion inhibitor for at least one of iron, brass, aluminum, or magnesium present in the concentrate in an amount having a weight percent of about 0.1% to about 3.0% relative to total weight of the concentrate;
• a strong base or weak base;
• and
• a thickening agent, present in the concentrate in an amount having a weight percent of about 0.75% to about 5.0% relative to total weight of the concentrate;
• wherein:
• the concentrate has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than 1.05 or greater than 1.95.

A forest fire retardant final diluted product, comprising:

• a retardant compound comprising a phosphate salt;
• a corrosion inhibitor for at least one of iron, brass, aluminum, or magnesium present in the final diluted product in an amount having a weight percent of about 0.1% to about 3.0% relative to the total weight of the final diluted product;
• a buffering agent present in the final diluted product in an amount having a weight percent of about 7% to about 56% relative to the total weight of the final diluted product;
• a thickening agent, present in the final diluted product in an amount having a weight percent of about 0.75% to about 5.0% relative to the total weight of the final diluted product;
• and
• water;
• wherein:
• the final diluted product is intended for use to suppress, retard, or contain forest fires;
• the pH of the final diluted product is about 6.0 to about 6.5;
• the final diluted product has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) of less than 1.05;
• and
• the retardant compound is present in the final diluted product in an amount having a weight percent of about 6% to about 28% relative to the total weight of the final diluted product.