Frequently Asked Questions

Q. MaP is a good measure for solid waste removal, BUT it doesn’t measure how well the flush action cleans the inside of the bowl. Why don’t you have a test for that?

A. You are correct, ALL_MaP_PREMIUM-HETs only for bulk waste removal in a single flush. There are other tests performed during the required certification process that look at bowl wash and splashing. Every fixture sold and installed in North America must meet certain minimum bowl wash requirements and must not splash above the rim of the bowl. We believe that until better tests are developed for these two measures, those certification tests are adequate to satisfy consumer expectations.

Q. We have heard that pressure-assist toilet fixtures are very noisy when compared to the traditional gravity-fed toilets installed in most homes. Is the noise a serious factor and why don’t you measure it?

A. We do not measure noise because it is seldom a deciding criteria in toilet selection. Also, testing for noise would require some substantial investment in facilities that we do not believe are warranted. We’ve learned that many of today’s new pressure-assist toilets are almost as quiet as many traditional gravity-fed toilets, due largely to the investment by the plumbing industry in the past few years in designs that reduce the noise of operation. As a consequence, the majority of pressure-assist toilets sold today are installed in residential applications, something unheard of as recently as the 1990s.

Q. The toilet that we want to purchase is not on your MaP list. Why?

A. There are three possible reasons. First – perhaps the model is new and is expected to be MaP tested shortly. Second – almost all manufacturers conduct MaP testing on their own toilet models in their own laboratories before they ever send models to an independent MaP-approved laboratory for testing. Therefore, the manufacturers know ahead of time what MaP score a given toilet will likely achieve when it is “officially” tested by a MaP-approved laboratory. If a toilet model does not perform well in their own testing, they will NOT submit the model for “official” MaP testing by a MaP-approved lab. That model, then, will never appear in our MaP listings. Since MaP testing is voluntary, the toilet model can still be sold in marketplace (provided it passes the required certification tests), but it does so without a MaP score being attached to it.  Of course, we ONLY recommend the purchase of toilet models that have been MaP tested.  Third – When toilet models are discontinued by a manufacturer, they are removed from our listings at the request of the manufacturer.

Q. Some of the toilet models on your MaP list show no MaP score.  Why is this?

A. Toilets without a MaP score have not been MaP tested.  Instead, we display the model on our list only because it has been certified to meet the U.S. EPA WaterSense specification for tank-type toilets.  That specification provides for a simple pass-fail test at 350 grams.  MaP, on the other hand, tests the toilets to their point of failure, hence the term ‘Maximum Performance’.  As noted above, we ONLY recommend the purchase of toilet models that have been MaP tested.

Q. Who pays for all this testing work?

A. Manufacturers pay a testing fee to a MaP-approved independent testing laboratory. That fee covers the work associated with the testing itself as well as for the formal test reports used by MaP Testing to list the product. Independent testing can be performed by a variety of MaP-approved laboratories.

Q. Can we ask for a product to be tested or is that service only available to manufacturers?

A. Yes, you may select a product to be tested. You would have to provide the product itself to a MaP-approved laboratory and pay their testing fee, which varies by laboratory organization (we have no control over what charges laboratories may impose for MaP testing). Each laboratory is required to provide you with a test report at the conclusion of the test.

Q. How did you come up with the 250 gram and 350 gram thresholds?

A.  These minimum performance thresholds of 250 grams (approx. 9 ounces) and 350 grams (about 12 ounces) were chosen as a result of medical and other studies performed on humans, each of which measured the amount of solid waste deposited at each ‘sitting’.  The 250 gram threshold represents the 95th percentile of all males (or, to put it another way, 95% of all males will deposit 250 grams or less or solid waste at a ‘sitting’.  The 350 gram threshold represents the 99th percentile.  As a result, initial MaP recommendations set a 250 gram performance minimum for toilets to be ‘qualified’ as acceptable.  Later, that number was increased to 350 grams and the U.S. EPA followed with their WaterSense Program also selecting 350 grams for their tank-type toilet specification

You may download the three medical studies that were consulted by MaP in developing the two performance threshold levels by visiting our ‘Background’ page.

Q. We noticed that you test both tank-type toilets and flushometer valve-bowl combination toilets for commercial applications. I would think that the demand upon a commercial toilet is quite a bit higher, since people seem to flush all kinds of material that we wouldn’t flush at home, such as seat covers, paper towels, and other objects. Shouldn’t MaP use a different test for commercial toilets?

A. Yes, you are correct. Not only are there bigger “demands” on a toilet installed in a commercial (or public) location, but these toilets must also withstand some degree of physical abuse as well.  MaP is in the process of addressing waste demands with a more rigorous set of testing requirements that will set apart those toilets that can successfully handle these higher demands. We expect that this “commercial MaP test” will be available in early 2016.

Q. We noticed that the maximum MaP score is 1,000g (2.2 pounds). Just to be safe, shouldn’t we limit our interest to only those models that achieve the highest score of 1,000g?

A. While there is nothing wrong with limiting your interest to models that flush 1,000 grams, you may be doing yourself a disservice. The U.S. EPA’s WaterSense program sets the minimum flushing performance level at 350 grams (12 oz). This level represents approximately the 99th percentile – or, in other words, in 99 times out of 100 the actual mass flushed in a toilet is less than 350g. We feel that any toilet model that flushes 500 grams or more would provide exceptional flushing performance. What’s more, some of the most efficient, stylish, and cost-effective toilet models have MaP scores of less than 1,000g.

Q. We all know that toilets flush liquid waste (i.e., urine) far more frequently than solid waste (i.e., feces) – some literature suggest that the ratio of liquid waste to solid waste flushes is 4:1 or even 5:1. Yet it seems like dual-flush toilets – which are designed to take advantage of the high ratio of liquid waste flushes – are only given credit for a ratio of 2:1. Why?

A. While it is widely believed that North Americans urinate 4 or 5 times more frequently than they defecate, there is currently no independent evidence that dual-flush toilets are subjected to this same ratio. The best evidence at this time points to a flushing ratio of something LESS THAN 2 liquid flushes for every single solid flush.  Read this document for more information on the topic of dual-flush and ‘effective flush volume’.  Furthermore, the effective flush volume MaP PREMIUM-rated dual-flush toilets is computed on a ratio of 1:1.

Q.  Where can we purchase the soybean paste for testing?

A.  To purchase the soybean test media (cased or in bulk), contact:
Gauley Associates, Ltd.
Acton, Ontario, Canada
Bill Gauley:  bill@gauley.ca
Office: 416-677-6193