ANSI Z358.1-2014 Explained: The 10-Second Rule, 15-Minute Flush and Tepid Water

Short answer: ANSI/ISEA Z358.1-2014 requires an eyewash station within 10 seconds' travel of a hazardous area, delivering tepid flushing fluid at 0.4 GPM (1.5 L/min) for a full 15 minutes, activated hands-free in one second or less, and inspected weekly.

Most buyers read the standard once, remember "15 minutes", and then specify on price. The four numbers below are the ones an auditor or a customer's EHS team will actually test.

The four numbers to specify before you compare quotations

Two further details are frequently missed. First, the flow pattern must sit between 33 and 53 inches above the standing surface - the 2014 edition replaced the older single nozzle-height figure, so much published guidance online is still out of date. Second, the unit must be at least 6 inches from a wall or obstruction so the user can position both eyes in the stream.

Hands-free activation is not a convenience feature

The valve must open in one second or less with a single motion, and it must stay open without being held. A worker whose eyes are contaminated cannot see, cannot find a small lever, and cannot hold a valve open for 15 minutes. This is why foot pedals, push plates and stay-open ball valves matter more than bowl finish or frame colour.

When we build a station, the valve is the first component we specify and the last one we test. A station that looks compliant on a datasheet but needs a hand on the lever will fail a real incident.

What ANSI does not cover

ANSI Z358.1 is a consensus equipment standard, not a law. In the United States it becomes enforceable through OSHA 29 CFR 1910.151(c), which requires suitable facilities for quick drenching or flushing of the eyes and body where corrosive materials are present. ANSI is the accepted definition of "suitable", which is why inspectors cite it.

If you export to Europe, the governing document is the EN 15154 series instead. The two are close in intent but not identical in test method, so a single specification should never mix clauses from both.

Frequently asked questions

Is 15 minutes of flushing really necessary?

Yes. The duration is set by the time needed to dilute and remove a corrosive substance from the eye surface, and it applies to the equipment, not to the incident. A gravity-fed portable unit with a 15-minute capacity is compliant; a plumbed unit that runs dry in four minutes is not.

Can a personal eyewash bottle replace a station?

No. Bottles are supplementary equipment for the first seconds after exposure. They cannot deliver a hands-free 15-minute flush, and they do not replace a plumbed or gravity-fed station within 10 seconds of the hazard.

Does the standard apply to a small laboratory?

It applies wherever the hazard exists, regardless of headcount. A two-person lab using corrosive reagents still needs a compliant unit within 10 seconds - often a wall-mounted or bench-top model rather than a full combination shower.

How often must the unit be activated?

Plumbed units must be activated weekly to verify flow and flush the line, with a more thorough annual inspection. Gravity-fed and self-contained units follow the manufacturer's schedule, which is usually more frequent.

Choosing equipment that meets the numbers

Compliance is easier to verify when the specification is written around measurable values rather than product names. Ask for the flow rate at the stated pressure, the valve opening time, and the temperature range the unit is designed to hold.

Our eyewash station range includes pedestal units, wall-mounted models and combination shower and eyewash stations, each supplied with a flow test record. If you are comparing options for a specific site, send us the hazard list and water supply data and we will size it with you.

Sources: ANSI/ISEA Z358.1-2014 summary (blog.ansi.org); OSHA 29 CFR 1910.151(c); CCOHS emergency shower and eyewash guidance.