Powder Coverage = 192.3/Specific Gravity/Mils x Transfer Efficiency
At first glance, you’re probably wondering where this mystery 192.3 number is coming from? Well, it turns out that that number is the Powder Coating Industries’ standard. The number is equal to the square footage coverage per one pound of powder at a standard specific gravity of 1.0 and a thickness of 1 mil with 100% transfer efficiency. What this all boils down to is that it’s a benchmark for one pound of powder which we can then use to help determine coverage based on more real-world inputs.

SPECIFIC GRAVITY
Specific gravity is a measure of molecular weight. These values are in our product application guides. NOTE: not all powders have the same specific gravity value.

TRANSFER EFFICIENCY
Transfer efficiency is the percentage of powder that adheres to your part. This number is completely subjective, but keep in mind that at 100% you’d have zero waste and zero overspray in your application. Everything from equipment to experience to setup can be determining factors for this value. Transfer efficiency is affected first and foremost by the setup of the spray gun as well as proper grounding. Kilovolt and microamp adjustments (if
you gun has them) provided by spray gun manufacturers, are there to assist in adjusting transfer efficiency.

Typically, the KV number (0-100) represents the voltage potential (percentage) available. Microamps manage the delivery of the voltage (KV) potential. The two settings work in conjunction to enable the applicator to find the best setting for maximum transfer efficiency for the given project/conditions. These settings will change due to variable factors and conditions including: part substrate, powder used, part shape, climate, humidity, etc. There is a misconception that a setting value of 100 will achieve the best results. This is not always true due to the above mentioned factors.

MIL THICKNESS
Mil thickness is the coating thickness measured in “mils” (.001 of an inch, not millimeters). Your desired mil thickness will come down to user preference and the job requirements. We highly recommend using a digital mil thickness gauge as this is the most effective and accurate way to measure mil thickness.