Lead in drinking water is a “quiet hazard.” You can’t see it, smell it, or taste it — and the highest-risk populations (infants and young children) may have no immediate symptoms even when exposure is occurring.

For EHS and facilities managers, the core challenge is this:

Even if the water entering your building meets utility standards, lead can be introduced at the point of use (POU) by building plumbing components (fixtures, fittings, solder, interior piping) and by usage patterns (stagnation over weekends/holidays).

This article focuses on actionable, defensible steps you can implement to (1) comply with California requirements where applicable, and (2) reduce risk with a program that holds up under scrutiny.

1) Regulatory context in California (AB 2370) – know what’s required

California Assembly Bill 2370 (AB 2370) created lead testing requirements for many licensed child care centers (CCCs), particularly those operating in buildings constructed before January 1, 2010, with initial testing required by January 1, 2023 and retesting every five years after the initial test.

The key concept for managing results is the state Action Level:

If lead exceeds an Action Level of 5 parts per billion (ppb), required response actions are triggered. Those actions include taking the affected outlet out of service and providing an alternative potable water source while remediation is planned and implemented.

Why this matters for EHS/facilities leaders:

“Compliance” defines minimum cadence, not minimum risk. A five-year cycle can still leave long periods of unknown exposure if your building has older plumbing, has undergone renovation, or experiences long stagnation periods.

2) What the testing results have shown (why you should treat this as a real exposure pathway)

An analysis of California’s reported child care testing results found that about a quarter of centers that complied had at least one outlet above the state’s 5 ppb level.

Some reported results were extremely high, illustrating that lead at the tap can be a severe, localized problem – not a subtle “slightly elevated” condition.

EHS takeaway:

Do not use “one outlet tested fine” to infer that all outlets are fine. Lead is often localized to a specific fixture, branch line, screen/aerator, or segment of plumbing.

3) Lead at the tap: sources, terminology, and why “lead-free” can still matter

Key sources in buildings

The most common sources of lead in drinking water include lead pipes, faucets, fixtures, and lead-containing solder/fittings. Corrosion and stagnation can increase lead release into water.

Important terminology for program design

• ppb (parts per billion): a concentration unit commonly used for metals in water.
• Action Level (program trigger): a practical threshold that requires response actions (e.g., 5 ppb in California’s child care program). It is not the same as “safe.”
• MCLG (Maximum Contaminant Level Goal): EPA’s health-based goal for lead in drinking water is zero.
• “Lead-free” is not “lead-zero”: Under the Safe Drinking Water Act definition, “lead-free” allows a weighted average of up to 0.25% lead across wetted surfaces for pipes/fittings/fixtures (and 0.2% for solder/flux). That means “lead-free” components can still contain small amounts of lead, and under certain conditions can contribute to lead measured at the tap.

Health framing:

CDC notes there is no safe blood lead level identified for young children. From a prevention standpoint, the defensible position is to reduce exposure as much as practicable, rather than treating compliance thresholds as “safe.”

4) A defensible program: inventory → risk-rank → test → act → verify

The fastest way to build a program that’s both practical and defensible is to use a repeatable management cycle:

1. A) Build an outlet inventory (POU map)

Create a list (and simple map) of every outlet used for:

• Drinking water
• Food preparation
• Bottle preparation / infant formula prep
• Ice machines connected to potable water (if used for consumption)
• Any “informal drinking” outlets (break rooms, classroom sinks used for cups, etc.)

Include outlet attributes that actually help decision-making:

• Outlet type (fountain, faucet, bottle filler)
• Location/room
• Primary use (drinking vs handwashing vs food prep)
• Fixture age (if known)
• Stagnation risk (rarely used, seasonal rooms, after-hours areas)

1. B) Risk-rank outlets (so you spend money where it matters)

Prioritize outlets with:

• Infant/child consumption relevance (bottle prep sinks, drinking outlets)
• High stagnation risk (weekend/holiday closures, low-use wings)
• Older plumbing/fixtures or unknown history
• Recent plumbing work (disturbance can change conditions)

1. C) Use an established sampling approach (don’t improvise)

EPA’s “3Ts” guidance provides a widely used approach for schools and child care. A key recommended method is 2-step sampling at the tap, taken after an 8–18 hour stagnation period:

Step 1 – 250 mL first-draw sample:

• Collect a first-draw sample at outlets used for consumption to identify lead that may be coming from the fixture/outlet and nearby plumbing.

Step 2 – 250 mL flush sample after 30 seconds (if Step 1 is elevated):

• Helps differentiate between lead from the fixture/outlet versus lead from interior plumbing behind the fixture.

Important technical notes that matter in the real world:

• Don’t use results from one outlet to characterize all outlets – lead can be highly localized.
• Consider aerators/screens: particulate debris can drive spikes; cleaning and retesting may help isolate a maintenance issue versus an upstream plumbing issue.
• Document stagnation time, sample ID coding, exact outlet, and chain-of-custody.

1. D) Interpret results using the right decision logic

For California child care centers under AB 2370:

• If an outlet result exceeds 5 ppb (Action Level), treat it as a required response condition:

1) Take the outlet out of service for drinking/cooking use

2) Provide a safe alternative potable water source

3) Implement corrective actions (see hierarchy below)

4) Retest to confirm the corrective action is effective

Even outside California:

If you serve vulnerable populations, the risk management approach should still be:

“Elevated lead at the tap triggers immediate exposure reduction + root-cause correction + verification,” not signage-only workarounds.

5) Controls and corrective actions (use a hierarchy; don’t rely on “workarounds”)

Think in terms of durable controls first, then administrative “bridges” while durable fixes are implemented.

Engineering / source removal (preferred for long-term prevention)

• Replace high-lead or older fixtures/outlets (especially drinking fountains and bottle fillers)
• Replace angle stops/connecting components if implicated
• Address interior plumbing segments if Step 2 indicates upstream contribution
• If a lead service line is present (less common in some settings), coordinate with the water provider on replacement strategy and post-work flushing/monitoring

Point-of-use (POU) filtration (common and effective, but only if managed correctly)

• Use filters certified by an accredited third party for lead reduction (commonly NSF/ANSI 53 for lead, and NSF/ANSI 42 for particulate class).
• Treat filters like a preventive maintenance item, not a “set and forget” purchase:

– assign ownership

– track replacement intervals

– document cartridge changes

– verify performance via retesting

Administrative controls (supporting controls; not a permanent fix by themselves)

• Flushing protocols:

– Useful for reducing lead from stagnation, particularly after weekends/holidays/closures.

– Must be documented (who/when/how long) and audited.

– Not a substitute for fixing a lead-contributing fixture or plumbing source.

• “Cold water only” for consumption/cooking (hot water can increase lead levels).
• Clear communication and signage for outlets out of service (and removal of signage once remediation is verified).

6) Documentation that protects people — and protects you

For EHS and facilities managers, documentation is not bureaucracy – it’s your defense that the program is real.

Minimum recommended records:

• Outlet inventory and outlet IDs
• Sampling plan + sampling procedures (including stagnation assumptions)
• Lab reports and chain-of-custody records
• Corrective action log (owner, due date, interim controls, permanent fix, retest date/result)
• Filter maintenance logs (model, certification basis, cartridge change dates)
• Communication log (how/when results were shared with stakeholders)

7) Practical facility checklist (copy/paste for internal use)

• Do we have a complete inventory of all drinking/food-prep/bottle-prep outlets?
• Do we risk-rank outlets based on use and vulnerability (infants/young children)?
• Do we have a sampling plan that uses first-draw (and follow-up flush sampling when needed)?
• Do we have a defined “action workflow” for results ≥ 5 ppb (take outlet offline, provide alternative water, correct, retest)?
• Are fixture replacements and filters procured using verifiable lead-reduction criteria?
• Do we have a preventive maintenance schedule for filters and flushing, with assigned ownership?
• Do we retest after corrective actions to confirm controls are effective?

Bottom line

Lead at the tap is a facilities-controlled exposure pathway. For child care environments, the right standard is not “did we test once,” but “do we have an ongoing system that finds problems early, reduces exposure immediately, fixes root causes, and verifies effectiveness through retesting.”