How We Score Products

Every product on CarCareTruth receives up to three scores. Each is computed from publicly available safety data, ingredient analysis, and editorial research — not manufacturer claims. Below is the full methodology for each score so you can verify our work.

CCT

CCT Score

The CCT Score is our headline rating — a composite “would I recommend this?” number on a 1–10 scale. It's computed in two stages from three rubric components plus an editorial opinion.

Stage 1 — rubric output

Three category-specific rubrics each produce a 1–10 score:

Quality — does the product do what it claims, within its category? Each product category (ceramic coatings, all-purpose cleaners, polishers, etc.) has its own internal scoring rubric that grades effectiveness against the standards real users hold it to. See Quality Score below.
Health — risk to a home user. See Health Score below.
Environment — realized environmental impact. See Environment Score below.

The three components combine using a category-appropriate weight profile. The mix differs by product kind — health weighs heavier for chemicals than for durable tools:

Profile	Quality	Health	Environment	Used for
chemical-standard	60%	25%	15%	Most chemical products (shampoo, wax, coatings)
tool-standard	75%	15%	10%	Durable tools (inflators, pressure washers, towels)
fluid-standard	65%	20%	15%	Operating fluids (washer fluid, coolant)

Stage 2 — editorial opinion overlay

The rubric output is then blended 75 / 25 with a separate CCT opinionscore (1–10) — a small, deliberate editorial layer that captures things the rubric can't formalize: real-world reputation, durability over time, brand track record, customer-service patterns, and the kind of judgment an experienced owner forms after years of using a product.

When we haven't formed that judgment yet, we say so. A product whose editorial review is still pending carries a neutral placeholder of 7.0 rather than a real opinion, and its score breakdown labels that line “not yet reviewed” so you can see exactly which part of the composite is a genuine call and which is a placeholder. The placeholder is deliberately neutral rather than flattering, and it is the only part of our scoring that is not yet earned.

stage1     = (Quality × wQ) + (Health × wH) + (Environment × wE)
composite  = (stage1 × 0.75) + (cct_opinion × 0.25)

How real-world feedback factors in

Scores are computed from the rubric — they are not nudged up or down by a running tally of comment ratings or Amazon stars. What user feedback doesdo is inform the editorial process: when readers report something the rubric didn’t catch — a durability failure, a fragrance issue, an application quirk — that’s a signal to revisit the rubric inputs and rescore. The displayed number doesn't move silently.

Confidence Levels

Level	Meaning
verified	All three rubric components scored from primary sources (SDS on file, complete chemistry, external corroboration of quality)
provisional	Quality scored from product and community data, but independent owner corroboration is still limited; chemistry and hazard data are complete
partial	Missing data in Health or Environment — typically no SDS on file for a chemical
unrated	Not enough information to score (provisional placeholder before research is complete)

Health Score

The Health Score (1–10, one decimal) reflects realistic risk to a home detailer — not industrial worst-case, not regulatory theater. We start at 10.0 and deduct for identified hazards using publicly available SDS and GHS data.

What the Health Score measures

Every CarCareTruth Health score is built around one question: how risky is this product to a normal adult using it the way the label intends— opening the bottle, applying it to a car, breathing the vapor that escapes, and getting some on their hands? That's the score. We do not score ingestion pathways, accidental child exposure, or spill cleanup as primary factors — those are handled by the GHS pictograms and signal words shown separately on the product page, and by standard household storage practice.

A product with H304(an aspiration hazard if swallowed) can still earn a relatively high Health score because adults don't drink penetrating oil. The aspiration hazard is real and is surfaced prominently in the safety panel — it just isn't the deciding factor in whether the product is risky to use as intended.

The score doesn't replace the label.Every product carries the manufacturer's GHS classification (signal word, hazard statements, pictograms) verbatim on its page. When our score and the label seem to disagree, follow the label — and see /disclaimer for the full editorial scope.

Deduction-Based Method

“Start high, deduct” makes the score explainable: each line item corresponds to a verifiable data point you can check against the product’s SDS.

Tier 1 — Critical risks (max −6.0)

GHS Signal word DANGER: −2.0
H330 (fatal if inhaled): −3.0
H334 (respiratory sensitizer) or confirmed asthmagen: −2.5
H314 (skin corrosion/burns): −2.0
H318 (serious eye damage): −1.5
Contains PFAS: −2.0
Prop 65 warning on label: −1.5
H350 (carcinogen Cat 1): −2.0 — hard cap at 4.5

Tier 2 — Major risks (max −4.0)

Signal word WARNING: −0.5
H317 (skin sensitizer): −1.0
H335 (respiratory irritation): −0.75
H315/H319 (skin/eye irritation): −0.3 each
High VOC: −1.0 (additional −0.5 if ≥500 g/L)
Extreme pH (≤2 or ≥12.5): −1.0

Tier 3 — PPE burden (max −2.0)

Respiratory PPE required: −1.5
Respiratory PPE recommended: −0.5
Eye/skin PPE required: −0.25

Form Factor & Concentration

Aerosols cap at 9.0 (inherent inhalation vector). Sprays apply lung-related deductions at 1.25×. Ingredient concentration modulates deductions: <1% halves the penalty, >10% increases it by 25%.

Bonuses & Hard Caps

EPA Safer Choice certification adds +0.5. No GHS signal word adds +0.3. Products confirmed carcinogenic (H350) cannot exceed 4.5; respiratory sensitizers (H334) cannot exceed 5.5.

Score Labels

Score	Label
9.0–10.0	Minimal Risk
7.0–8.9	Low Risk
5.0–6.9	Moderate Risk
3.0–4.9	Elevated Risk
1.0–2.9	High Risk

Health Score Disclosure

This score is CarCareTruth editorial opinion based on publicly available safety data — Safety Data Sheets, GHS classifications, and regulatory listings. It reflects estimated risk for typical home-user application and is not a medical assessment, regulatory determination, or substitute for reading the product label and SDS. Always follow manufacturer safety instructions.

Environment Score

The Environment Score (1–10, integer) reflects realized environmental impactfrom typical consumer use. Design principle: harm = (intrinsic toxicity × persistence) × exposure pathway.

Baseline & Pathway Modifier

Every chemical starts at 7.0. Rinse-off products (car wash soaps, wheel cleaners, degreasers) multiply all deductions by 1.25× because they enter waterways directly. Leave-on products (coatings, sealants, dressings) multiply by 0.75×.

Deductions

Bio-persistence

Contains PFAS: −3.0 (hard cap: max score 3)
Bioaccumulative ingredient: −1.5 per compound (max −3.0)
Persistent non-PFAS ingredient: −1.0 per compound (max −2.0)
Ozone-depleting substance: −2.0 (hard cap: max score 4)
Microplastic ingredient: −1.5 per ingredient (max −2.5)

Aquatic toxicity

Product-level aquatic toxic flag: −1.5
Per-ingredient aquatic toxicity: −1.0 each (max −2.0)

VOC load

0–50 g/L: no deduction
51–150 g/L: −0.5
151–350 g/L: −1.0
351–550 g/L: −1.5
>550 g/L: −2.0

Credits (Positive Attributes)

EPA Safer Choice: +2.0
Product-level biodegradable: +1.0
All ingredients biodegradable: +0.5 (stacks)
CARB compliant: +0.5
Waterless/rinseless formulation: +1.0

Score Labels

Score	Label
9–10	Best Available
7–8	Environmentally Responsible
5–6	Average
3–4	Notable Concerns
1–2	Significant Concerns

Quality Score

The Quality Score (1–10) reflects how well the product performs its core function — assessed on dimensions specific to the product category. What "quality" means varies: for a spray sealant it means hydrophobicity durability and application ease; for a motor oil it means viscosity spec compliance and additive-package credibility; for a polishing pad it means cut consistency and durability. The score is not about packaging or branding.

Category-specific dimensions

Each product category has its own quality rubric. Common dimensions include:

Spray sealants & ceramic sprays — hydrophobicity durability, application ease, formula transparency, gloss enhancement
Coatings — cure window, scratch resistance, durability (years), application tolerance
Motor oils & fluids — viscosity grade accuracy, API/OEM spec compliance, additive-package documentation
Tools & pads — build materials, cut/finish consistency, durability over cycles, ergonomics
Accessories — load rating accuracy, fitment, long-term durability

When a category-specific rubric has not yet been applied, the quality score defaults to a provisional 6.5 — a neutral baseline reflecting a typical well-documented product with no notable performance complaints.

Data sources

Sources vary by dimension but typically include: SDS and TDS ingredient/spec disclosures, the Amazon review corpus (complaint pattern analysis), community forum testing (AutoGeek, Optimum Forum, r/AutoDetailing), and independent long-term reviews. No dimension score is editorial opinion — each requires at least one documented external source.

Weight in composite

Quality weight varies by product type: 60% for most chemicals (sprays, waxes, coatings), 65% for spec fluids (motor oil, coolant, washer fluid),70% for high-exposure chemicals where the chemistry forces every product to a similar health score, and 75% for tools and accessories where build quality is the dominant value driver. See the full weight-profile table above.

Score Labels

Score	Label
9.0–10	Exceptional
7.5–8.9	Well Made
6.0–7.4	Adequate
4.0–5.9	Subpar
1.0–3.9	Poor Quality

Worked example

Here's a sample chemical product (the chemical-standard weight profile) scored end-to-end so you can see all three rubrics and the two-stage CCT Score in one place. Every product page on the site shows its own per-row breakdown.

Health Score: 8.9 — Low Risk

Starting score:                            10.0
Signal word: WARNING                       −0.5
H315 (skin irritation)                     −0.3
H319 (eye irritation)                      −0.3
PPE eyes: required                         −0.25
PPE skin: required                         −0.25
Biodegradable + no PFAS bonus              +0.2
Active 1–5% in water (concentration band)  +0.3
                                            ────
Final:                                      8.9

Environment Score: 9.0 — Best Available

Baseline (chemical):                       7.0
No aquatic toxicity                        +1.0
No PFAS                                    +0.5
CARB compliant                             +0.5
                                            ────
Final:                                      9.0

Quality Score: 8.0

Built from the category-specific Quality rubric — active-ingredient analysis, manufacturer technical literature, verified-purchase sentiment, and owner-community consensus. Every product category has its own internal rubric file that defines the criteria for that specific use case.

CCT Score: 7.6 — Recommended

Weights (chemical-standard):  Q 60%  H 25%  E 15%

Stage 1 — rubric output:
  Quality      8.0 × 60%  →  4.80
  Health       8.9 × 25%  →  2.23
  Environment  9.0 × 15%  →  1.35
                              ────
  stage1                       8.38

Stage 2 — editorial overlay:
  stage1 × 0.75              + 6.28
  cct_opinion (7.5) × 0.25   + 1.88
                              ────
  composite                    8.16  → 8.2

(Worked example uses stage1 only as a sanity check; the
 published number on the product page is the stage-2 composite.)

Confidence: provisional — quality is based on documented chemistry, manufacturer technical literature, and verified-purchase owner sentiment, with independent long-term owner data still limited.

Per-category scoring guides

The rubric above applies a category-specific lens. Every category we score has its own guide spelling out exactly which dimensions count and why:

Transparency & Rubric Versioning

All scores store the rubric version used at scoring time (currently v2.0). When we update the methodology, we bump the version — existing product scores display which version they were scored under, and re-scoring happens on the next editorial pass, not retroactively.

Sponsored products are scored identically to non-sponsored products. Affiliate links never alter rankings or scores. A sponsored review is still a real review.

Questions about our methodology? Contact us.