FAQ

Many IR faucets infer “hands present” from reflected IR energy. Mirror finishes, glossy basins, chrome trim rings,
and high-contrast lighting can shift return signal behavior enough to cross the detection threshold.

Mitigation approach: define activation stability during commissioning (repeatability under installed lighting),
then tune range or shielding, and verify at multiple times of day.

Supporting reference
IR pulse discrimination
Lavatory context

“Activation delay” must be test-defined: start condition (hands entering zone), stop condition (first continuous flow),
and repetition (multiple trials per sink position). Report median and worst-case results, not just averages.

Measurement alignment
CSA testing context

Basin geometry and mounting height determine impact point, splash return, and how droplets travel toward the sensor window.
Shallow bowls and tight drain zones can create upward splash that intermittently blocks or confuses detection.

What to document: spout height above rim, reach vs drain centerline, spray type (laminar vs aerated), and splash travel.

Splash / aerosol evidence
Building & Environment paper
University summary PDF

Static pressure can look acceptable on a gauge, while dynamic pressure can collapse under real demand because of undersized piping,
long runs, partially closed stops, strainer loading, or high simultaneous use. Commission under realistic load when possible.

Flow expectations
EPA performance basis
EPA commercial guidance

Outlet choice changes splash and aerosol behavior, perceived “softness,” and clogging modes.
Treat the decision as a system choice tied to basin depth, impact point, and infection-control intent.

Evidence
Basin dispersion study
Flinders summary PDF

Low flow complaints are often combined effects: outlet clogging, upstream debris loading, stop throttling,
hot/cold imbalance at mixing points, and dynamic pressure loss under occupancy peaks.

Field check sequence: aerator/laminar device inspection, stop verification, strainer/solenoid screen check (if present),
then timed-fill flow verification to remove “feel” bias.

Flow & performance context
EPA commercial faucets
CSA research PDF

Central tempering can stabilize temperature sink-to-sink but creates loop balancing and a single point of drift.
Point-of-use mixing localizes failures but increases the number of devices that must be accessed, calibrated, and documented.
For large buildings, align temperature strategy with a building water management program where required.

Water safety + guidance
CDC WMP toolkit
ASHRAE 188

First-draw temperature is dominated by branch conditions and purge time. Touchless cycles can be short enough that the line never fully stabilizes,
especially when hot water is distant or the tempered loop is not balanced. Include an “overnight stagnation” first-draw check in commissioning.

Commissioning context
CDC toolkit PDF

Treat batteries like filter media. Define a replacement interval by traffic class, stage spares, and log replacements by asset ID.
If you do not define the plan, the building will drift into ad hoc “dead faucet” maintenance.

O&M structure support
EPA commercial faucets

In hardwired or hybrid systems, poor connections or supply instability can present as random resets, intermittent activation, or unexpected shutoff.
Separate “sensor tuning” from “supply stability” in your troubleshooting tree and document power routing at turnover.

Controls context
IR sensor behavior

The concern is not “touchless” by itself. It is the interaction of internal faucet geometry, low flow, water age,
and remediation effectiveness after disruptions. Risk management should align with facility infection control practices and water management programs.

Healthcare evidence
Johns Hopkins article
APIC/ASHE PDF
CDC toolkit

Define a water management program that identifies where water age increases, then implement routine flushing protocols (manual or automated),
verify temperatures where relevant, and document corrective actions and verification methods.

Program framework
CDC WMP PDF
ASHRAE 188

Touchless can reduce operability burden, but the lavatory still must support forward approach clearances,
and any related operable parts (soap, towel, overrides, valves where user-accessible) must be coordinated with reach and approach conditions.
Treat this as a layout coordination item, not a late punch-list fix.

Accessibility guidance
Lavatories guide
Operable parts
2010 ADA Standards

Keep it short and keyed to sink position. Include sink numbering, underside photos, power method, settings as-left,
flow verification results, and a mapped spares list tied to asset IDs.

Acceptance logic
EPA performance basis
CSA research PDF

Run repeat cycles at a controlled hand position and observe droplet travel to deck, backsplash, and sensor-window area.
Document pass/fail with photos on the worst basin geometry and highest flow configuration.

Evidence
Basin dispersion study
University summary PDF