ASSE 1016 Shower Valve Meaning: Types, Scald Protection and Limits

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ASSE 1016 is the performance standard for automatic compensating shower valves, the valves that keep the water temperature steady at an individual shower or a tub and shower combination. The shower valve asse 1016 meaning comes down to three things: which valve types the standard covers, what job the valve is meant to do, and what the installer must set at installation. The sources below are a state residential code reference, an ASSE International guidance paper, a manufacturer’s standards chart and a manufacturer’s comparison page. The paper and the chart are the most useful for the meaning, and the comparison page is included because it disagrees with them on one point.

Quick answer

ASSE 1016 covers automatic compensating valves for an individual shower or a tub and shower combination, and it is published with matching ASME and CSA designations.
The ASSE International guidance paper says there are three valve types that meet the standard: pressure balancing, thermostatic (mechanical and electronic), and a combination of pressure balancing and thermostatic.
The paper says these valves provide both scald and thermal shock protection, and it says the temperature limit stop must be set at installation.
Leonard Valve’s standards chart describes the standard as covering shower and tub valves only, and it says the valve must shut down quickly when cold water is lost.
Fontana’s comparison page describes ASSE 1016 pressure balance valves as not giving anti-scald protection. That conflicts with the ASSE paper, so the paper and the code text should be preferred for the meaning.

What ASSE 1016 covers

The Massachusetts residential code text on UpCodes refers to the standard in its shower control valve section. It says that “Individual shower and tub/shower combination valves shall be balanced-pressure, thermostatic or combination balanced-pressure/thermostatic valves that conform to the requirements of ASSE 1016/ASME 112.1016/CSA B125.16 or ASME A112.18.1/CSA B125.1.” The code therefore uses ASSE 1016 as one of two accepted routes for the same kind of valve. It is the route for the individual shower valve, and it is one of the valve references a state code can point to.

The ASSE International guidance paper gives the scope in plain language. It says the shower valves “shall be automatic temperature and/or pressure compensating valves intended to be installed at an individual shower or tub/shower combination.” The paper’s section on this device adds that the valves are intended “to control the water temperature to wall- or ceiling-mounted” outlets. It lists hand-held showers, shower heads, body sprays, and tub spouts that are part of a tub and shower combination fitting. The meaning of the standard is therefore about the shower outlet, not the sink or the bathtub alone.

Leonard Valve’s chart says the same thing in its own words. It says “This is the standard for shower and tub valves only.” That line is useful because it separates ASSE 1016 from the sink and lavatory standard, which is a different device family. A shower valve listed to ASSE 1016 is therefore not the right device for a sink, even when both are thermostatic.

The three valve types

The ASSE paper says “There are three different types shower valves that meet this standard:” and then lists them. The first type is pressure balancing. The second type is thermostatic, which the paper lists as mechanical and electronic. The third type is a combination of pressure balancing and thermostatic control, which responds to both.

Leonard’s chart uses the same three designations. It says the valve “May be listed as Type P, Type T or Type T/P.” It also gives a simple example: “A thermostatic or pressure-balanced valve in a shower.” The designations P, T and T/P are the labels a product marking may show, so a homeowner should look for the letter on the trim or the packaging when choosing a replacement valve.

The Massachusetts code text allows the same three families. It refers to balanced-pressure, thermostatic, and combination balanced-pressure and thermostatic valves. The state text and the ASSE paper therefore agree on the valve families, even though they use different wording. The difference is that the code describes what is allowed, while the paper describes what the standard covers and how the valve is used.

What the valve is meant to do

The ASSE paper says these devices “provide both scald and thermal shock protection.” Scald protection is about keeping the outlet water from getting too hot. The paper names thermal shock protection as a second, separate protection, and it states the two together for this valve family. The sources here do not explain the internal mechanism of each valve type, so the protection claims should be read as the paper’s statements, not as a mechanical description.

Leonard’s chart frames the purpose the same way, describing the device as one that controls the water temperature at wall-mounted showerheads in individual showers or tub and shower combinations, to reduce the risk of scalding and thermal shock. The chart also gives the performance test in its own words. It says the key test is that the valve must “shut down to less than 0.5 GPM on cold water loss within 5 seconds,” which describes how quickly the valve must cut the flow when the cold supply is lost.

The paper also gives a set of installation rules. It says “The showerhead flow rate must not be less than the manufacturer’s published minimum flow rate for the valve (device).” It says “The temperature limit stop must be set at the time of installation, and may need to be periodically adjusted for variations in water temperatures.” It also says “The user has access to flow and/or final temperature controls. No further mixing occurs downstream of the device.” The last sentence matters because a shower valve listed to ASSE 1016 is the final control, not a stage in a mixing chain.

Where a manufacturer page disagrees

Fontana’s comparison page describes the two valve families as thermostatic valves tied to ASSE 1070 and pressure balance valves tied to ASSE 1016. It presents the pressure balance valve as giving approximate control and no anti-scald function. Its table row for anti-scald protection marks the pressure balance type as not providing it, and it describes that type as suited to gyms, airports and cost-sensitive projects.

That description conflicts with the ASSE paper, which says that the ASSE 1016 device types provide both scald and thermal shock protection. The paper also lists ASSE 1070 as a different device for sinks, lavatories, bidets and bathtubs. The two sources do not describe the same device in the same way, so a homeowner should not rely on the Fontana table for the meaning of ASSE 1016. For the scope and protection of the standard, the ASSE paper and the state code text are the better sources. The Fontana page is useful mainly as an example of how sales material can blur the lines.

The conflict also shows why the marking on a product matters more than a general description. A valve should be checked against the code and the manufacturer’s installation sheet for its specific listing, not only against a comparison page.

What to check on a valve marked ASSE 1016

Confirm the marking says ASSE 1016, and note whether the valve is listed as Type P, Type T or Type T/P.
Check that the valve is for an individual shower or a tub and shower combination, not a sink or lavatory.
Confirm the showerhead flow rate is not below the manufacturer’s published minimum for the valve, as the ASSE paper requires.
Set the temperature limit stop at installation, and plan to check it again if the hot water temperature changes over time.
Confirm that the code in your jurisdiction accepts the valve type. The Massachusetts text used here accepts balanced-pressure, thermostatic and combination valves that conform to ASSE 1016 or ASME A112.18.1 and CSA B125.1.

What the sources do not settle

The sources do not settle the exact performance numbers for every edition of the standard. The ASSE paper uses the 2011 edition designation, and Leonard’s chart uses a 2017 designation. The two dates are not the same, so the edition that a product or a code references should be confirmed before purchase. The sources also do not give the test procedure, and they do not give a list of every listed valve.

The Massachusetts code text is a state residential code reference from a published copy. A homeowner should confirm the edition and any local amendments with the local building department before relying on the wording. The Fontana page is a manufacturer’s commercial comparison, and it should not be used to define the standard.

FAQ

Is ASSE 1016 the same as ASSE 1070? No. The ASSE paper describes ASSE 1070 as a standard for devices that limit the temperature of water supplied to fixtures such as sinks, lavatories, bidets or bathtubs. ASSE 1016 is for the individual shower and tub and shower combination valve.

Does ASSE 1016 mean a valve is thermostatic? No. ASSE 1016 covers three valve types: pressure balancing, thermostatic and a combination of the two. The letter on the marking shows which type it is.

Why does the meaning matter for a replacement? A replacement valve should match the type the local code allows, and it should be installed with the temperature limit stop set and the flow rate checked. Those steps are part of what the standard is meant to protect.

How we chose

The meaning of the standard was taken from the ASSE International paper and the Leonard chart, because both describe the standard’s scope and purpose. The Massachusetts code text was used to show how a state code refers to the standard. Fontana’s page was included because it disagrees with the other sources, and the disagreement is reported rather than resolved by choosing one source silently. Quoted phrases were compared with the saved text before the draft was saved.

What we could not verify: what the sources do not say

We could not read the ASSE 1016 standard itself, because its text is not freely available in the saved sources. The description here comes from a guidance paper, a manufacturer chart and a state code reference. We did not verify the test values in the standard, the edition in force for a given product, or the listing of any specific valve. The Fontana page could not be checked against the standard, and its numbers are reported only as what the page says.

Related guides

Sources

UpCodes, Chapter 27 Plumbing Fixtures, Massachusetts Residential Code, 10th edition (as shown on UpCodes), https://up.codes/viewer/massachusetts/irc-2021/chapter/27/plumbing-fixtures (opened 2026-10-30). State residential code text for shower control valves.
ASSE International Scald Awareness Task Group, Guidelines for Temperature Control Devices in Domestic Hot Water Systems (white paper), https://asse-plumbing.org/media/pbfltxqk/asse_guidelines_for_temp_control_devices.pdf (opened 2026-10-30). Association guidance on scope, valve types and protection.
Leonard Valve Company, ASSE Standards: Making Sense of It All chart (October 2020), https://www.leonardvalve.com/api/image/ASSE%20Standards%20&%20Chart-%20Making%20Sense%20of%20It%20All%20(Oct2020).pdf (opened 2026-10-30). Manufacturer standards chart.
Fontana Showers, “Thermostatic vs Pressure Balance Shower Valves,” https://www.fontanashowers.com/thermostatic-vs-pressure-balance-shower-valves-s/12114.htm (opened 2026-10-30). Manufacturer comparison page, cited for a point where it disagrees with the other sources.