Years and years ago, there was a "code" for pistol sprayers.
White trigger and nozzle, for water and less agressive solvents such as alcohol.
Blue trigger and nozzle for water and surfactants.
Red trigger and nozzle for hydrocarbon solvents.
Then, yellow trigger and nozzle for acid based products.
The differences were the materials used for the "o-ring seal and what they used for the "spring", metal.
Back 15 years ago, over 80's of consumer sold spray nozzles were Continental, most made in Indonesia, not the one's that came on your deoderant, hair spray, but like most are addressing here.
Then, some other manufacturers stepped up to bat and started to produce spray nozzles that met the requirements of what the nozzles were to be used for, other than the mass consumer product market.
An example would be the "yellow" nozzle and body, they used a better o-ring that was acid and solvent resistant, and upgraded the spring to a steel. These changes allowed the nozzle to last longer, keep spraying longer.
Then, they finally realized that Vitron was the most chemical resistant, at a reasonable cost, was the way to go for the o-ring seal.
This o-ring is what allows the pumping of the trigger to build and hold pressure until the trigger releases it.
Next step, the "spring'.
They finally started to use "stainless steel" for the spring of the trigger unit.
Stainless is pretty durable when exposed to acids, alkalines, solvents, etc. so it's did not suffer the corrosion of the material and lose the ability to pump the trigger system.
The Vitron seal, coupled with the stainless steel spring resulted in the modern day, chemical resistant trigger sprayers that are on the market today.
The color of the nozzle and trigger that was used when all this came about was "grey", but now aday's, who knows.
So, to recap, 8 to 10 years ago, the color was an indicator of what the trigger sprayer was intended to be used for.
Today, who knows, just find ones that have stainless for the spring and Vitron for the o-ring seal.
Grumpy
