I recently put together a simple doser for manually measuring accurate doses of sanitizer into wash water solutions. It is really just a homemade burette. The process of mixing a treatment dose of santizer requires metering a specific dose of concentrate into a larger volume of water. I have also created a calculator to help with that. The UVM Extension Produce Safety Program maintains a great set of resources for general guidance on use of sanitizers including this guide sheet. It is important to always have a copy of the official product “label” (not necessarily the same thing as the label on the container). For easy reference, labels for typical sanitizers are linked below. Please check with your supplier to be sure you have the most recent version for the product you are using and the intended application.
There are a number of options available to avoid actually pouring these chemicals when dosing a mix tank. You can download a summary of these options here. When pouring them, splashing and spills can occur which are best avoided due to the corrosive and hazardous nature of the chemicals at stored concentrations. Even when using enclosed dispensing options, wear proper personal protective equipment including goggles and resistant gloves in case there are unexpected leaks or spills.
Some of the dispensing options available include:
- Dosatron – $940-$1000 – Allows for injection of sanitizing chemical directly into the flow stream of water being used in the process. Measurement is done by adjusting flow ratio similar to a fertigation system.
- Goat Throat – $299 – GoatThroat 300 Pump with Viton seals. Allows a manual, enclosed pumping with integral valve. No closed measurement.
- EnviroSelect Dispensing Pump (BioSafe Safety Value Pack) – $75 – Allows a manual pumping of liquid directly from container without pouring. No integral valve, and no closed measurement.
When I reviewed these options, I felt there was still a need for something at the lower end of use volume. Something that would work for 30 to 300 gallon washing batches. So that is why I put together the assembly that is posted on FarmHack with a parts cost of less than $50 and assembly time of less than 1 hour. I think it may be helpful. Let me know what you think, and feel free to join in the design discussion on FarmHack.