Customer questions:
Is the stated test psi the required psi or the minimum psi?
Can the SpiroPure ____ membrane operate at ___ psi?
Internal note: Have you confirmed we offer a compatible model? The best way for us to serve the customer is to get a model number off their existing part to see if we offer a compatible SpiroPure membrane. If it is not listed on the chart, we cannot say whether or not the membrane will operate correctly in their system.
Template answer:
The test pressure indicated for the product (on our website or in the data sheets) is neither a minimum nor required pressure — it's simply the standardized condition used to measure the stated performance. The membrane will operate at lower pressures with reduced flow rates, but there is also an effective minimum pressure range (typically 50–100 psi for most applications, depending on the membrane) below which performance would be significantly compromised.
Said another way, the psi is neither "required" nor "minimum," just the lab test to demonstrate the pressure needed for a specific water quality (NaCl in ppm) to achieve the stated flow rate and fresh water recovery rate.
Importantly, RO membrane performance will vary based on the customer's input water quality, temperature, system specifications, and operation.