How it works
Final SH = pickup concentration × chemical parts ÷ (water parts + chemical parts). A 10:1 ratio here means 10 parts water to 1 part chemical solution, not 1 part chemical in 10 total parts. If your pickup container is premixed, use that premixed concentration.
Worked example
With 12.5% SH in the pickup container and 10 water parts to 1 chemical part, the mathematical outlet concentration is 1.1364%.
Related contractor resources
Frequently asked questions
Can I use the ratio printed on my injector?
Use it only as an estimate and check how the manufacturer defines its ratio. Draw changes with nozzle, hose length, pressure, viscosity and equipment condition.
How accurate is the result?
It is only as reliable as the entered draw ratio and source strength. A manufacturer-approved draw test is more useful than treating a nominal ratio as guaranteed.