Ensure PPE is worn.
A chemical test kit is required to assess whether the chemical characteristics comply with the requirements for effective cleaning.
The test should be conducted on cleaning solutions that have been made up but not used.
The tests to conduct are given in the Table below.
Chemical test parameters for cleaning solutions
| Test Parameter | Range | Comment |
|---|---|---|
| Alkali was pH level | 11.5-12.5 | If a non-chlorine alkaline detergent is used, adjust pH level to 12.5 |
| Alkali wash Active Alkalinity | 800-2,000 ppm | Based on soil load. refer to the tablet below or Table 14 on page 35 in the Australia Dairy Hygiene Handbook |
| Chlorine level | Minimum 70 ppm 100 ppm for sanitising 140 ppm for very heavy soil load |
|
| Acid wash/sanitiser pH level | 2.5-3.5 |
Guideline for levels of active alkalinity based on soil loads
| Soil load conditions | Example | Active Alkalinity (ppm) |
|---|---|---|
| Light | Small dairies (<13 units) with small pipelines (<63 mm diameter), and short milking times (<1.5 h). Practice good milking hygiene | 800 |
| Medium | Medium-sized dairies (<25 units), and medium milking times (<2h). Practice good milking hygiene | 1,000 |
| Heavy | Large dairies, large diameter pipelines, longer milking times, or practice ‘average’ (no teat preparation) milking hygiene | 2,000 |
Before adjusting chemical dose rates, it is imperative to verify that the ‘presumed’ chemical dose is actually being delivered. Capture the chemical as it is dispensed to make the verification.
A specialised test kit is required to determine qualities such as active alkalinity (AA) and chlorine levels. Dairy chemical representatives are usually the best starting point to working out which type of test kit is most appropriate for assessing dairy farm water and cleaning solutions. Furthermore, the performance of some cleansers/sanitisers may be best assessed using different or additional tests.
