5.2 Lead-Based Paint Definition and Component Language
Key Takeaways
- Lead-based paint is present on any surface tested and found to contain lead equal to or in excess of 1.0 milligrams per square centimeter or equal to or in excess of 0.5% by weight, and on like surfaces in the same room equivalent with a similar painting history (40 CFR 745.227(h)(1)).
- XRF reports loading in mg/cm²; paint-chip analysis reports concentration in percent by weight. Either threshold is enough. Inconclusive XRF is not a pass — chip analysis or another documented method has to finish the determination.
- A component or building component is distinguished by form, function, and location. Window sashes, sills or stools, troughs, jambs, and heads are separate components, not one “window.”
- Distinct painting history means the application history of paint or other surface coatings to a component or room, shown by visual appearance or a record of application. Inspectors test each component with a distinct painting history; supervisors read that map on the work order.
- Do not abate a component the inspection report determined is not lead-based paint, and do not skip a listed LBP component because it is “just trim.” Post-1978 replacement components may already have been excluded by the inspector.
Two numbers, either one is enough
Quick Answer: Lead-based paint is present on any surface that is tested and found to contain lead equal to or in excess of 1.0 milligrams per square centimeter or equal to or in excess of 0.5% by weight, and on any surface like a tested surface in the same room equivalent that has a similar painting history and that is found to be lead-based paint (40 CFR 745.227(h)(1)). XRF speaks in mg/cm². A paint chip speaks in percent by weight. Hit either threshold and the coating is LBP.
745.223 defines lead-based paint as paint or other surface coatings that contain lead equal to or in excess of 1.0 milligrams per square centimeter or more than 0.5 percent by weight. The determination you will see on an inspection report — and the one you use to decide what the crew abates — is 745.227(h)(1): ≥ 1.0 mg/cm² or ≥ 0.5% by weight. 0.5% by weight is 5,000 parts per million (ppm) of lead in the dried film. Varnish, stain, and other coatings are in the definition; “it is stain, not paint” is not an automatic out.
Pre-1978 construction is why the building is target housing or a child-occupied facility (Chapter 3). It is not a field test for LBP. A 1952 door casing can be below both thresholds. A 1977 sash can be above either one. You abate what the report (or a contract assumption that all paint will be treated as LBP) identifies. You do not abate “the whole house because it is old.”
XRF vs paint chip — two languages, one definition
| Method | What it measures | Unit that maps to the definition | Supervisor reading |
|---|---|---|---|
| XRF (x-ray fluorescence) | Loading — mass of lead per area of the painted surface | mg/cm²; LBP if ≥ 1.0 | Look for the performance-characteristic sheet (PCS) cut-point, the serial number, and whether the reading is positive, negative, or inconclusive |
| Paint-chip laboratory analysis | Concentration — lead as a fraction of the dried film | % by weight; LBP if ≥ 0.5% (5,000 ppm) | Substrate must not dilute the film; results come from an EPA-recognized (NLLAP) laboratory |
Either path can establish LBP. A sash at 1.2 mg/cm² is LBP even if nobody ever cut a chip. A baseboard chip at 0.62% by weight is LBP even if the XRF was never used. A sash at 0.4 mg/cm² is not LBP by the loading test; it can still be LBP if a chip on that same distinct painting history comes back ≥ 0.5%. Inconclusive XRF is not a pass. Documented methodology then requires a chip (or another accepted method) to finish the determination. Chapter 7 is where you practice reading the report. This section is the definition the report is using.
Worked example — mixed results in one room. Living-room window sash: XRF 1.4 mg/cm² → LBP. Living-room window trough: XRF 0.3 mg/cm², no chip → not LBP on that component unless a like-surface rule applies. Living-room door casing: inconclusive XRF, chip 0.71% by weight → LBP. You do not “average the room.” You do not treat the trough as LBP just because the sash is. You also do not skip the casing because the XRF was inconclusive.
Like surfaces and distinct painting history
745.227(h)(1) has two sentences. The first is the number on the tested surface. The second expands it:
Lead-based paint is also present on any surface like a surface tested in the same room equivalent that has a similar painting history and that is found to be lead-based paint.
You do not need an XRF shot on every identical sash in the room if they share a similar painting history and the tested one is LBP. You do need a separate determination when the painting history is not similar.
Distinct painting history (745.223) is the application history, as indicated by visual appearance or a record of application, over time, of paint or other surface coatings to a component or room. A 1970 living-room sash that was never stripped, sitting next to a sash the owner stripped to bare wood and recoated in 2015, are not the same painting history. An inspector who treats them as one component has a sampling error. A supervisor who writes one method for both because “they are both windows” will abate the wrong film or skip the one that is still LBP.
Inspection practice (745.227(b)(2)) matches that idea: in a dwelling or COF, each component with a distinct painting history, and each exterior component with a distinct painting history, shall be tested, except components the inspector or risk assessor determines were replaced after 1978 or do not contain LBP. In multi-family, common-area components with distinct painting histories are tested too. Supervisors do not re-run the inspection. They read which components were tested, which were assumed by like-surface, and which were excluded as post-1978 replacements.
Component language a supervisor sees on a work order
Component or building component (745.223) means specific design or structural elements or fixtures distinguished from each other by form, function, and location. The regulation’s list is the vocabulary of your work order, not decoration.
| Interior components (examples in 745.223) | Exterior components (examples in 745.223) |
|---|---|
| Ceilings, crown molding, walls, chair rails | Painted roofing, chimneys, flashing |
| Doors, door trim, floors, fireplaces | Gutters and downspouts, soffits, fascias, rake boards |
| Radiators and other heating units, shelves, shelf supports | Cornerboards, bulkheads, doors and door trim, fences |
| Stair treads, risers, stringers, newel posts, railing caps, balustrades | Floors, joists, lattice work, railings and railing caps, siding, handrails |
| Windows and trim, including sashes, window heads, jambs, sills or stools, and troughs | Stair risers, treads, stringers, columns, balustrades |
| Built-in cabinets, columns, beams, bathroom vanities, counter tops, air conditioners | Window sills or stools and troughs, casings, sashes and wells, air conditioners |
Form, function, and location is why “do the windows” is not a method. A sash is a moving friction surface. A sill or stool is the interior horizontal ledge (also the interior window sill in 745.63). A trough (window well) is the exterior pocket that receives the sashes — a post-abatement action-level surface, not the same component as the sash. A jamb and a head are frame parts. Replacing sashes and leaving LBP troughs in place is a different job from replacing the entire assembly. Encapsulating a wall is not enclosing a sash. Scraping a door because the knob hammers the stop is an impact story (Section 5.3), not a “paint all wood” story.
Room equivalent matters for the like-surface rule. A room (745.63) is a separate interior part divided by built-in walls or archways that extend at least 6 inches from an intersecting wall. Half walls and built-in bookcases can count; movable partitions do not. A screened porch used as a living area is a room. Do not copy a living-room sash result onto a bedroom sash just because both are “windows in the unit.” Different room equivalent, unless the report actually tested or grouped them.
Work-order traps
| Work-order line | What a supervisor should unpack |
|---|---|
| “Abate all windows, living room” | Which components: sashes, heads, jambs, sills/stools, troughs, casings? Which are LBP on the report? Replacement, enclosure, or paint removal on each? |
| “Scrape and encapsulate walls” | Encapsulation is a permanent method (abatement) only if a true encapsulant is specified as a barrier. Confirm the report’s LBP walls vs. non-LBP walls. Unsuitable surfaces are Chapter 12. |
| “Replace trim” | Trim is many components (door trim, window casing, chair rail, baseboard), each with its own painting history. |
| “Treat all paint as LBP — no inspection” | That is a contract assumption, not a 745.227(h)(1) determination. It can be a legal work method if the owner pays to treat everything, but it is not the same as an inspection finding. |
| “Skip the 1995 replacement windows” | Inspectors may exclude components replaced after 1978. If the report already did, do not re-add them as LBP. If original 1960 troughs remain under 1995 sashes, those troughs may still be in play. |
Worked example — similar painting history. Four identical living-room sashes, same original color visible at the edges, no record of stripping. Inspector XRFs one sash at 1.6 mg/cm² and applies 745.227(h)(1)(ii) to the other three. The work order that replaces all four living-room sashes is reading the definition correctly. The bedroom sashes, different color stack, were tested separately at 0.2 mg/cm² — they are not pulled in by the living-room result.
Worked example — the “negative” casing. A 1971 door casing is 0.3 mg/cm² and a chip is 0.21% by weight. Both are below the definition. The house is still target housing. You do not abate that casing as LBP. You may still have dust-lead or soil-lead hazards in the same unit (Section 5.3). LBP on a component and a hazard in the unit are different findings.
Read components the way the inspector built the report: one distinct painting history at a time, form/function/location, like surfaces only inside the same room equivalent. That is the language your occupant protection plan and abatement report will have to repeat.
Under 40 CFR 745.227(h)(1), when is lead-based paint present?
An inspector XRFs one of four identical living-room window sashes at 1.6 mg/cm². The four sashes share the same visible color stack and there is no record of stripping. Bedroom sashes in the same dwelling show a different color stack and were not tested. Which statement matches 745.227(h)(1)?
A work order says “abate all windows in the living room.” Under the 40 CFR 745.223 definition of component or building component, what must the supervisor unpack before choosing methods?