No code or manufacturer guide we checked sets a replacement interval for urinal screens. Follow the screen product's label, and replace one when it is clogged, worn or no longer sits flat. Never run a drain without its strainer: Kohler and Zurn both say to keep the strainer in place, and to clean it during scheduled service.
Is there a required replacement interval for urinal screens?
No. OSHA's sanitation standard, 29 CFR 1910.141, says only that "All places of employment shall be kept clean to the extent that the nature of the work allows," and that waste must be removed "as often as necessary or appropriate to maintain the place of employment in a sanitary condition." That is a duty, not a calendar.
The product label is the next authority. Disposable deodorizer and splash screens are accessories sold by many brands, each with its own stated life. Follow the one on the package, and do not stretch it past the point it clogs or loses its shape.
What is the difference between a screen and a strainer?
A strainer is the part sitting over the drain opening. It catches debris before the drain does. A screen in everyday restroom talk is usually a disposable mat or cover that sits in the bowl and carries a deodorizer or cuts splashing. Check which one your maintenance staff is talking about before you set a schedule.
For the strainer, both major sources we read treat it as a fixed part, not a consumable. Kohler's waterless urinal guide says, "Always keep the strainer in place over the urinal drain to prevent debris from entering the drain." Zurn's sheet for its waterless urinal says "Do not remove the strainer" once the sealant is in the trapway, because removal "will result in the loss of the sealant and reduce the life of the sealant."
How often should you clean around the strainer?
On the maker's maintenance cycle. Kohler's waterless urinal calls for a flush-out cleaning every two weeks. In it you lift the strainer out with "a small screwdriver or bent wire," clean it and set it aside, flush the trap, then "Reinstall the strainer." Kohler also tells you to "Remove the used urinal ball and discard," and to "Set a fresh urinal ball in the urinal." In that routine the urinal ball is the part that gets replaced on schedule, each flush-out.
Zurn's cycle is use-based, not date-based. Its sheet calls for adding 3 to 4 ounces of sealant "after every 3,000 uses" and a trap cleaning "Every 9,000 uses," with the strainer removed for that cleaning. Which counts as "every two weeks" or "every 3,000 uses" depends on traffic, so a busy restroom reaches it sooner.
Can the wrong screen or puck cause trouble?
Yes, on some fixtures. Kohler says not to use cleaners containing anti-bacterial agents, "or any other urinal puck or mat, as these may reduce the effectiveness of the urinal ball." Zurn says to "Avoid dumping aggressive cleaners and/or large amounts of liquids down the urinal drain," because doing so can deplete the sealant and "allow sewer gases to back up into the restroom."
So the right screen on a waterless urinal is the one the maker sells for that fixture. Check the manual before you drop in an add-on. For how those cartridge and sealant systems work, see waterless vs flush urinals and do waterless urinals cause sewer odor.
What are signs a screen or strainer needs attention now?
- It is clogged or caked with debris, so the urinal drains slowly. Compare why urinal lines clog with uric scale.
- It is cracked, bent or missing pieces. Replace the part from the fixture maker.
- The urinal smells even after cleaning. Check the seal first, as in the odor page above.
On a waterless model, EPA says to "regularly clean and replace the seal cartridges or other materials as specified by the manufacturer and follow all other manufacturer-provided guidance."
Put the strainer check on the same log as the rest of the restroom, as part of a commercial plumbing preventive maintenance plan. If a urinal will not drain after cleaning, the problem is probably further down the line. HQ gives free estimates for commercial drain and restroom work.