# Exercise mats: research notes

Date: 2026-10-25. Scope: flat mats used as the surface under the body during yoga, pilates, stretching and general floor exercise (HIIT, core work, weight training, gymnastics-adjacent floorwork) — both thin rollable mats and thicker folding/tri-fold fitness mats. Covers the full mat_material space the add-on already lists (PVC, TPE, natural rubber, cork, jute, NBR, EVA, suede microfiber, polyurethane). Does not cover: yoga props (blocks, straps, bolsters, wheels — sibling `yoga-equipment`), balance pads/wobble boards (sibling `balance-equipment`), foam rollers (sibling `foam-rollers`), camping sleep pads (sibling `sleeping-bags`, different job: insulation and packed size, not grip or balance), or protective pads for contact sports (sibling `protective-sports-gear`). Where a product could plausibly sit in either bucket (e.g. a thick foam gym "crash mat"), the line is use: if it's underfoot for exercise, it's here; if it's for falling onto or sleeping on, it's a sibling's.

Quote labels: **verbatim** = text I read myself, either via pdftotext on a downloaded PDF or via curl plus HTML tag-stripping (the method used for every brand/retail page below — see `striptags.py` in the scratchpad), so the exact sentence is what the page served. **fetched excerpt** = the WebFetch tool's own model summary of a page, used only for two pages (OEKO-TEX, AAAAI) before I re-fetched them raw with curl to confirm the wording; the verbatim version is what's cited in category.json. **search excerpt** = none used; WebSearch reported its budget exhausted before any query ran, so every source below was reached by direct curl/WebFetch on a known or guessed URL, or by following links found on a fetched page.

Could not reach: REI's yoga mat buying guide (curl returned nothing, likely TLS/bot block), OutdoorGearLab's yoga mat page (HTTP 410, page removed), Verywell Fit's best-yoga-mats page (HTTP 402). No Internet Archive snapshots were needed since the brand and Jade/Liforme/SELF pages all loaded directly.

## Seed

Seed script output, recorded verbatim:

- Example: olive-oil `harvest_date` — "a facet that experts rank first, that almost no listing carries, and that is expensive to backfill. The honest answer is to list it, mark it researched, and limit backfill to the top of the catalog."
- Persona: "An allergist, who thinks in exposure, dose and what is hidden in the ingredients list"

1. **The yoga-mats equivalent of harvest_date is `grip_surface` (closed-cell vs open-cell).** It is the single best predictor of whether a mat feels grippy once you're sweating, and like harvest date it is almost never a structured field on a retail listing — it lives only in brand prose ("closed-cell construction", "moisture-activated microfiber", "open-celled... absorbent"). A novice has no idea to ask about it because nothing on a typical Amazon-style listing prompts the question. **Kept**, source `researched`, backfill limited to named brands for now, with a material-based inference rule for everyone else.
2. **What the allergist notices first: "latex-free" on a natural rubber mat is a claim about additives, not about the tree sap itself.** Jade Yoga's own product page says their rubber mats are "99% latex free... there may be trace amounts of latex proteins" and recommends people with latex allergies avoid contact — exactly the kind of label-vs-actual-exposure gap an allergist is trained to catch, and exactly the gap a typical buyer (who reads "latex-free" and stops thinking about it) would miss entirely. **Kept** as a judgement on `mat_material`, sourced to Jade's own disclosure plus AAAAI on what latex allergy actually reacts to (the protein, not a marketing label).

## Sources and what each supports

### Brand spec pages (read via curl + HTML strip, verbatim)

**Manduka, PRO Yoga Mat 6mm**
https://www.manduka.com/products/manduka-pro-yoga-mat
- verbatim: "The PRO is a high-density yoga mat... Crafted in Germany since 1997, it delivers floor-like stability... A hygienic, closed-cell surface keeps sweat, moisture, and bacteria out of your mat... backed by a lifetime guarantee."
- verbatim: "Weight: Standard 7.5 lbs. (3.4 kg); Long 9.5 lbs. (4.3 kg); Short 7 lbs (3.2 kg)" / "Dimensions: Standard 71" (180 cm) length × 26" (66 cm) width; Long 85"..."
- verbatim: "Crafted in Germany from PVC. The PRO Series is certified STANDARD 100 by OEKO-TEX® (12.HUS.17706 | Hohenstein) to keep you and your family safe from harmful substances." / "Latex-free"
- verbatim: "Because the PRO's closed-cell surface does not absorb moisture, the mat may feel slick if you're prone to sweat. We recommend pairing it with a [towel]."
- Supports: PVC + closed-cell + high-density framing, 6mm thickness, weight/dimensions for the density metric, OEKO-TEX certification with a real cert number, the closed-cell-can-feel-slick trade-off. Confidence high.

**Manduka, eKO Natural Rubber Yoga Mat 5mm**
https://www.manduka.com/products/eko-yoga-mat-5mm
- verbatim: "The eKO yoga mat delivers a textured natural grip that provides reliable traction in dry conditions. The closed-cell construction keeps moisture out for easy cleaning... Crafted in Taiwan from natural rubber with over 30% recycled content."
- verbatim: "Because the eKO's closed-cell surface does not absorb moisture, the mat may feel slick if you're prone to sweat."
- verbatim: "Like many natural rubber products, prolonged exposure to direct sunlight can dry the material over time, affecting its appearance and performance."
- Supports: natural rubber is not automatically open-cell (Manduka's own rubber mat is closed-cell) — this is why `grip_surface` is a separate facet from `mat_material`, not derivable from it alone. Also supports the UV/odor care trade-off on rubber. Confidence high.

**Manduka, Begin Yoga Mat 5mm**
https://www.manduka.com/products/begin-yoga-mat-5mm
- verbatim: "Material: TPE" / "Closed-cell surface seals out sweat, dirt, and bacteria for easy cleaning" / "With 5 millimeters of cushiony thickness..."
- Supports: TPE as a distinct material from PVC and rubber, also closed-cell. Confidence high.

**Manduka, ENDURA Fitness Mat 10mm**
https://www.manduka.com/products/endura-fitness-mat-10mm
- verbatim: "A 10mm cushion provides comfortable support for training, stretching, and floorwork... while reinforced construction stands up to shoes and daily wear." / "Material: Proprietary PVC foam with reinforced scrim" / "Dimensions: 71" (180 cm) length × 26" (66 cm) width" / "Weight: 6.6 lbs (3 kg)"
- Supports: the shoes-on fitness mat as a distinct, thicker (10mm), reinforced product from the barefoot yoga line at the same brand — direct evidence for the `primary_use` split and `reinforced_construction`. Confidence high.

**Jade Yoga, Harmony Mat**
https://www.jadeyoga.com/products/harmony-mat
- verbatim: "3/16" thick, 24" wide, available in two lengths: 68" and 74", and weighs about 5 pounds." / "Jade mats contain no PVC, EVA or other synthetic rubber" / "Eco-friendly: Made with natural rubber tapped from rubber trees, a renewable resource."
- verbatim: "Please also note that our natural rubber mats are not intended for use outdoors and should not be exposed to sunlight."
- verbatim: "Although Jade mats are 99% latex free, as they are from rubber trees, there may be trace amounts of latex proteins in the mats so we recommend persons with latex allergies avoid contact with our mats."
- Supports: natural rubber material, 3/16in (≈4.76mm) thickness, weight, UV sensitivity, and the load-bearing latex-trace disclosure the allergy judgement rests on. Confidence high — this is the brand's own safety language, not a third party's interpretation.

**Jade Yoga, Jade Cork Yoga Mat**
https://www.jadeyoga.com/products/jade-cork-yoga-mat
- verbatim: "Made with sustainably harvested cork and natural rubber... contains no PVC" / "Cork provides outstanding grip for hot yoga or other sweaty practices" / "Natural rubber base provides more comfort and resilience."
- A customer review quoted on the page (not brand copy, so weighted lower): "It has more grip than any other mat I have used, especially when it's wet."
- Supports: cork-topped rubber mats marketed specifically for sweaty/hot practice, i.e. the open-cell/absorbent side of `grip_surface`. Confidence medium-high (brand marketing claim, but consistent with Liforme's and SELF's independent framing of absorbent surfaces).

**Liforme, How to Choose a Yoga Mat**
https://www.liforme.com/pages/yoga-mat-guide
- verbatim: "You might think that thicker means better... the right thickness actually finds the sweet spot between comfort and stability... Too thin and your knees and wrists feel every bit of the hard floor. Too thick and things start to get unsteady."
- verbatim: "Above about 6mm, you lose the connection to the floor that keeps you steady in standing balances."
- verbatim: "The cheapest mats are PVC, which is hard-wearing but difficult to recycle, and it can carry a chemical smell for weeks. TPE is lighter and softer, but it wears out very quickly. Natural rubber mats are made from a renewable material that breaks down at the end of its life, but tend to be hard, heavy, and have a strong odor."
- verbatim: "Standard mats are often 68 in (173cm), which leaves a lot of people running out of space."
- Supports: the thickness/stability trade-off (one of its two sources), the three-way material trade-off, and the too-short-standard-mat point. Confidence medium-high — this is a competing brand's own buying guide, so treated as a claim needing a second source, which SELF supplies for the thickness point.

**Liforme, Non-toxic Sustainable Materials**
https://www.liforme.com/pages/non-toxic-materials
- verbatim: "this ultra-thin layer has an open-cell structure that delivers a uniquely grippy, absorbent, and cushiony feel" / "designed to biodegrade within 1–5 years under normal landfill conditions."
- Supports: open-cell = absorbent + grippy framing, and the alignment-guide feature existing as a named category of thing brands build. Confidence medium (one brand's description of its own patented layer).

**Liforme, The Grippiest Yoga Mats**
https://www.liforme.com/pages/the-grippiest-yoga-mats
- verbatim: "PVC's closed-cell structure is inherently slippery. Moisture from sweaty palms, feet, and brows just sits on its surface like a puddle on pavement."
- Supports: the closed-cell-gets-slick-when-wet side of the grip trade-off. Confidence medium (a competitor's framing, but matches Manduka's own care instructions for its closed-cell mats, which is as close to an admission as a brand page gets).

**Yoga Design Lab, Combo Yoga Mat (Zenith)**
https://www.yogadesignlab.com/collections/combo-yoga-mat/products/combo-yoga-mat-zenith
- verbatim: "this mat fuses a natural rubber base with a moisture-activated microfiber surface for unmatched grip and convenience... the moisture-activated grip keeps you steady in every pose."
- Supports: a third brand's version of an absorbent/open-cell-style top layer, built specifically to get grippier with sweat. Confidence medium.

**ProsourceFit, Tri-Fold Folding Exercise Mat (6ft)**
https://www.prosourcefit.com/products/tri-fold-exercise-mat-6x2
- verbatim: "Whether you train clients, workout at home on hard floors, need to practice gymnastics tumbling, or do martial arts, a little extra cushion always helps... Dense foam protects sensitive joints... A durable and waterproof vinyl covering is easy to clean." / "Material: PVC; EPE Foam"
- Supports: the thick, folding, general-fitness side of the category (distinct product form from a rollable yoga mat but the same taxonomy leaf), PVC vinyl cover over foam, and the "stands up to shoes/weights" framing shared with Manduka's ENDURA. Confidence high for what the page states.

### Specialist review

**SELF, The Best Yoga Mats**
https://www.self.com/story/best-yoga-mats
- verbatim (product spec box, Manduka PRO entry): "Made of closed-cell material, which helps prevent sweat and moisture from soaking into the mat" / "Size: 71 x 26 in. | Thickness: 6 mm | Weight: 7.5 lb."
- verbatim: "Not as stable during balance-based exercises, since it's thicker" (con listed for the Bala Play Mat, 15mm).
- verbatim: "A thicker mat is ideal if you're practicing on hardwood or primarily using it for floor poses and stretching... some people may find it easier to balance and flow more dynamically on a thinner mat (typically under four millimeters)."
- verbatim: "Look for options made with open-celled materials like polyurethane foam, which is extra absorbent. (You'll still want to regularly clean your mat to prevent bacteria buildup.)"
- verbatim: "Most standard yoga mats are 71 or 72 inches long, but you can find options that are both shorter (68 inches) and longer (80 inches)."
- verbatim: "There are also textured yoga mats, which feature grippy nubs along the top that can give you more stability... 'You can also get mats with dual surfaces, featuring a smooth surface on one side and textured grip on the other.'"
- Supports: this is the independent second source for (a) the thickness/balance trade-off — an instructor-sourced "under four millimeters" band plus an explicit "not as stable... since it's thicker" verdict on a named 15mm mat — and (b) the open-cell = absorbent = needs-cleaning framing, matching Liforme's claim from the other side (a reviewer, not the brand making the absorbent product). Also supports the alignment-grid feature description (the Bala mat entry) and the too-short-standard-length point (a third source, after Liforme and Jade's own 68in listing). Confidence high — independently tested and instructor-quoted, not brand copy.

### Standards and medical

**OEKO-TEX, STANDARD 100 by OEKO-TEX**
https://www.oeko-tex.com/en/our-standards/standard-100-by-oeko-tex
- verbatim: "STANDARD 100 is a label for textiles tested for harmful substances. It sets the benchmark for textile safety, from yarn to finished product." / "Every thread, button and accessory have been tested against a list of over 1,000 harmful substances" / "Compliance with global regulations, including the annexes XVII and XIV of... REACH."
- verbatim (product classes): "Product Class 1: Products for babies and children up to 3 years... the strictest requirements."
- Supports: what the certification Manduka cites on its PRO mat actually tests for, and that it's an independent standards body rather than a brand's own claim. Confidence high — read directly from the standards body's page.

**AAAAI (American Academy of Allergy, Asthma & Immunology), Latex Allergy**
https://www.aaaai.org/tools-for-the-public/conditions-library/allergies/latex-allergy
- verbatim: "Natural rubber latex, a milky fluid found in rubber trees, is used to make some gloves, condoms, balloons, rubber bands, erasers and toys."
- verbatim: "With latex allergy, [the immune system] overreacts by producing antibodies... These antibodies travel to cells that release chemicals, causing an allergic reaction."
- verbatim: "People with this allergy have symptoms such as urticaria or hives, itching or flushing, swelling, sneezing, runny nose, cough, wheeze, shortness of breath, chest tightness, nausea, dizziness or lightheadedness. Any combination of these symptoms can be a sign of anaphylaxis."
- Supports: that the allergen is a protein present in rubber-tree latex itself (not an additive a brand can simply omit), and the severity range up to anaphylaxis — the medical backing for treating Jade's "99% latex free... trace amounts" disclosure as something that matters rather than marketing caution. Confidence high — a medical professional body's own consumer page, read raw.

## Data points used for derived metrics

- `apparent_density_kg_m3`: needs weight (Manduka PRO 3.4 kg, ENDURA 3 kg, Jade Harmony ~2.3 kg for the 68in at "about 5 pounds"), length × width (Manduka PRO 180 × 66 cm, Jade 173 × 61 cm), and thickness (PRO 6mm, Jade 3/16in ≈ 4.76mm). No source states a density number directly — "high-density" is marketing language in every brand's own copy (Manduka: "high-density mat with floor-like stability") — which is exactly why this is a derived metric rather than a facet: the inputs are on the listing, the output never is.

## Against the existing add-on schema

`zamana-expertise/data/schema-parts/supplies/active/add-ons/yoga_mat.jsonc` currently has two fields: `mat_material` (enum pvc/tpe/natural_rubber/cork/jute/nbr/eva/suede_microfiber/polyurethane/unspecified, flagged with the comment "trap: eco TPE vs natural rubber") and `sizing.thickness` (value + unit mm/in). Nothing in it is noise — it is already minimal, and both fields map directly onto this register's `mat_material` and `thickness_mm` facets, so neither needs to change. Proposals, using the AGENTS.md field-kind vocabulary (vertical anchor, category quality currency, hard filter, sizing):

- `mat_material` is doing the job of a **vertical anchor**: the fundamental fact (what it's made of) that every other material-driven claim (weight, odor, eco-ness, the TPE-markets-as-eco trap this register's sources confirm) hangs off. Already correct as-is; no change proposed.
- `sizing.thickness` is a **category quality currency**: dense, comparable, and already correctly inside `sizing` per AGENTS.md rule 2 (it is the one spec that genuinely varies by SKU/variant for an otherwise-identical mat). No change proposed.
- `grip_surface` (closed-cell vs open-cell), the strongest facet in this register, does **not** map cleanly onto `mat_material` — Manduka's own eKO (natural rubber) is closed-cell while Jade's cork-topped and Liforme's rubber+PU mats are open-cell/absorbent, so the two axes are independent and the schema currently has no field for this at all. It is a real candidate for a new field, but its `source: researched` / `backfill_cost: medium` status (see facet above) means it would not be densely populated the way a true category-quality-currency field needs to be (AGENTS.md rule 4). Recommendation: carry it in `high_signal_markdown` for now (it is exactly the kind of "construction and quality signal" that field exists for), and promote it to a structured boolean once a reliable backfill source (brand-copy scraping) proves it can hit good density.
- `reinforced_construction` (scrim/heavier vinyl for shoes-on use): same situation as `grip_surface` — real, sourced (Manduka ENDURA, ProSource), not visually reliable from a photo, but not dense enough yet for a structured field. Recommend `high_signal_markdown` for now rather than a new schema field.
- `oeko_tex_certified`: AGENTS.md rule 5 explicitly lists certifications as "dead under this regime — cut on sight" for structured schema fields, so despite being a real, standards-body-backed facet in this register (useful to the assistant and the UI), it should **not** be proposed as a schema field. It belongs in `high_signal_markdown` text only, consistent with the repo's current rule.
- `alignment_guides` (printed lines): this is visible in the product photo in essentially every case (it's a design printed on the mat's visible surface), so per AGENTS.md rule 1 it is visually-derived material and belongs to the image/embedding pipeline, not a schema field, even though it is a legitimate cold-start facet for this register and the dynamic UI.
- No change proposed to `active-standard.jsonc`'s `max_user_weight` or `supplies-standard.jsonc`'s generic `sizing` block — mat length and width are already covered by the generic `dimensions.length/width`, and mat weight by the generic `sizing.weight`, so the SELF-and-Liforme "standard length is often too short" point needs no new field, only better backfill of the existing generic ones.

## Branches

- `primary_use` = "Barefoot practice" → ask `grip_surface` next. Chain: barefoot contact means bare skin touches the mat, and every source that raises sweaty-grip as a concern (SELF, Liforme, Manduka's own eKO/PRO care instructions, Jade Cork, Yoga Design Lab) frames it specifically around yoga/hot-yoga practice, never shoes-on exercise. SUPPORTED.
- `primary_use` = "Shoes-on fitness" → ask `reinforced_construction` next. Chain: Manduka's own shoes-on mat (ENDURA) is the one line in its catalog built with "reinforced construction [that] stands up to shoes", and ProSource's tri-fold fitness mat separately markets a "durable and waterproof vinyl covering" for the same shoes/weights use; no barefoot-yoga product page in this research set mentions reinforcement. SUPPORTED.
- `mat_material` = "PVC" → ask `oeko_tex_certified` next. Chain: Liforme's own guide's claim that PVC "can carry a chemical smell for weeks" is the concern OEKO-TEX Standard 100 exists to address with an independent test, and Manduka's own PVC PRO mat is the one product in this research set that actually carries a stated OEKO-TEX certificate number — i.e. the certification question becomes relevant specifically once PVC is the chosen material. SUPPORTED, though the chain rests on one brand's cert example; noted as medium rather than high confidence in the facet's backfill_note. **2026-10-25 correction:** the facet's `why_experts_care` previously said "PVC and some synthetic mats can carry a chemical smell," which would have implied the branch should also cover TPE. Re-checked Liforme (PVC only) and Manduka's TPE Begin page (no smell claim at all) directly — nothing in this source set ties a chemical-smell concern to TPE — so the overgeneralization was removed from the prose instead of widening the branch. Leg stays PVC-only, now for a stated, sourced reason rather than by default. Also added a judgement that a cited PVC page (ProsourceFit) carries a mandatory Prop 65 vinyl-chloride warning distinct from the voluntary OEKO-TEX question this branch asks.
- Not added: a branch making `grip_surface` "irrelevant" on the shoes-on leg. SELF and Liforme's sweaty-grip framing is yoga/hot-yoga specific, but shoes-on floor exercise (burpees, planks, push-ups) still involves hand contact and sweat, and no source explicitly rules grip_surface out for that use, so I only note it as lower-priority there (captured in the `grip_surface` judgement) rather than claiming it stops mattering.
- Not added: a branch from `thickness_mm` to any other facet. No source ties a specific thickness band to a *different next question*, only to the stability/cushioning trade-off already carried in the facet's own `why_experts_care` and the first trade-off entry.
- **2026-10-25 correction:** removed `thickness_mm`'s `skip_if_known: ["primary_use"]`. That was not a `branches` leg but had the same effect (skipping a question based on an earlier answer), and the blind check was right that it overstated what `primary_use` tells you: knowing barefoot-vs-shoes-on narrows which half of the mm range a buyer is likely in, but not where in that half they want to sit, so it does not make `thickness_mm` fully redundant. `thickness_mm` is now always asked, with its thin/standard/thick-to-mm mapping moved into the split's own `rationale`.

## Trimmed detail

- `thickness_mm`: Manduka's PRO at 6mm is explicitly the brand's high end for barefoot use ("High-density, firm support"), while its own shoes-on ENDURA line starts at 10mm — the two product lines from one brand sit on either side of the 6-to-8mm gap this register's typical range leaves open, which is indirect support for treating 6mm as roughly where "standard" ends.
- `mat_material`: Liforme's guide is itself a PVC-free, pro-rubber brand's framing of PVC and TPE, so its "chemical smell" and "wears out very quickly" lines are a competitor's characterization, not an independent lab finding; I kept them because SELF and the brands' own closed-cell care instructions corroborate the mechanism (closed-cell doesn't breathe, so a chemical smell from a sealed PVC mat is physically plausible) even though no independent reviewer measured either claim directly.
- `grip_surface`: Jade's cork-mat customer review ("more grip than any other mat... especially when it's wet") is marked lower-confidence in the sources section above because it is a single customer quote, not brand copy or an independent test; it is not cited as evidence in category.json for exactly this reason, only the brand's own marketing line ("Cork provides outstanding grip for hot yoga") is.

## Corrections after the blind check (2026-10-25)

Re-fetched all sources touched below myself with curl + `striptags.py` (same method as the original pass; scratch copies in `/private/tmp/claude-501/-Users-amnbh-Desktop-dev-zamana/94e1e673-5231-41fe-8b68-7a624ab5c8d8/scratchpad/fix-yoga-mats/`). WebSearch's budget was exhausted again (same as the original research pass), so new sources were found by guessing brand URLs and confirming by direct fetch, not by search.

1. `thickness_mm.why_experts_care` and the first `tradeoffs` entry: removed the invented "10 to 15mm, noticeably less stable" band. Re-verified SELF's spec boxes myself — the "Not as stable... since it's thicker" con sits under the **Bala Play Mat (5mm)**, and the only product SELF ties to balance trouble by name is the **15mm All In Motion Premium Fitness Mat** ("probably too thick for balance-heavy workouts"). Both fields now cite only the under-4mm (SELF) and 15mm (SELF) data points plus the ~6mm Liforme threshold, with no invented band.
2. `judgements[0]` note (the ~6mm claim): reworded to say Liforme alone states the 6mm figure and SELF confirms the general direction (a 15mm mat too thick for balance) without naming a cutoff, instead of implying both sources state "6mm." Evidence list unchanged — both still back the general trade-off, just not the specific number.
3. `thickness_mm.range.min = 1.5`: re-sourced rather than dropped. Found the actual product the "1.5mm" nav crumb pointed to — Manduka's **eKO Travel Superlite Yoga Mat 1.5mm** (fetched directly, confirmed natural-rubber travel mat at 1.5mm) — and a second, independent source, Jade Yoga's **Voyager Mat** (fetched directly, "1/16\" thick" ≈ 1.5mm). Added both as new references (`manduka_eko_superlite`, `jade_voyager`) and added them to `thickness_mm.evidence`, so the minimum is now a real two-sourced figure instead of a nav-link artifact.
4. `thickness_mm.range.typical` and `why_experts_care`: dropped the uncited "8mm" fitness-mat floor. Checked SELF's own spec boxes again: an 8mm mat on that page is the JadeYoga XW Fusion, a **barefoot** mat for larger bodies, not a shoes-on product — so 8mm was never a real shoes-on floor, confirming the original finding and ruling out "round down from 10mm" as a fix. Changed typical to "10mm and thicker for shoes-on fitness mats," anchored only to Manduka's confirmed 10mm ENDURA.
5. `visual_grammars[0]` (Thickness range bar) and `thickness_mm.visual.encoding`: changed the second marked band edge from 8mm to 6mm, to match fix 4 and the facet's own sourced threshold instead of the dropped invented one.
6. `splits` entry for `thickness_mm`: added the thin/standard/thick-to-mm mapping directly into the split's `rationale` ("Thin means under about 4mm, standard 4 to 6mm, thick above 6mm..."), so the mapping lives in the split object itself rather than only in the facet's prose. Also dropped `skip_if_known: ["primary_use"]` — the finding is right that knowing barefoot-vs-shoes-on narrows the typical band but doesn't say where in it the buyer wants to sit, so treating the question as fully redundant overstated what `primary_use` tells you. `thickness_mm` is now always asked.
7. `mat_material` question (both `splits` and the facet's `cold_start_question`): reworded from "PVC, TPE, or natural rubber?" to "Cheapest and toughest, light but short-lived, or natural and heavier?" — sourced to Liforme's own three-way framing, re-confirmed verbatim on a fresh fetch ("The cheapest mats are PVC, which is hard-wearing... TPE is lighter and softer, but it wears out very quickly... Natural rubber mats are made from a renewable material... tend to be hard, heavy"). This passes the novice-answerable and generic-category tests the old question failed, while the three answers still map 1:1 onto the facet's unchanged `values` list (PVC / TPE / natural rubber), so no branch or filter value needed to change.
8. Added a new judgement: a cited PVC product (ProsourceFit's tri-fold mat) carries a mandatory California Prop 65 warning for vinyl chloride, confirmed by fetching the page directly ("WARNING: This product can expose you to chemicals including vinyl chloride, which is known to the State of California to cause cancer"), set against OEKO-TEX Standard 100 being voluntary. Also added that disclosure as a second `supports` line on the existing `prosource_trifold` reference. This states the mandatory disclosure the register was previously silent on, rather than explaining it away as out of scope.
9. `oeko_tex_certified.why_experts_care`: narrowed "PVC and some synthetic mats can carry a chemical smell" to "PVC mats can carry a chemical smell" — re-checked Liforme's guide and Manduka's TPE (Begin) page myself; only PVC gets a chemical-smell claim anywhere in this source set, TPE only gets "wears out very quickly." Since the overgeneralization is what the required fix's branch concern rested on, correcting the prose to match the sources resolves it: branch leg 3 (`mat_material = PVC → oeko_tex_certified`) stays PVC-only because PVC is the only material this register's sources actually tie to a chemical-smell concern, not widened and not left unexplained.
10. `oeko_tex_certified.definition`: dropped "including phthalates." Re-fetched OEKO-TEX's own STANDARD 100 page directly; it names "over 1,000 harmful substances" and REACH/CPSIA/ECHA-SVHC compliance, but never mentions phthalates specifically, confirming the finding. No replacement source found for phthalates specifically, so the phrase was removed rather than re-sourced.

Rejected: none. All seven required fixes were sourced and applied as above; no finding was judged wrong on re-checking.