Reduction and pressure sensitivity
Not medical advice. Planning literacy only — not diagnosis, medical compression advice, or a safe-constriction certificate.
Executive summary
Physical contact pressure from pattern reduction is not the same as how hard a region feels relative to clothing-comfort preference. Distal limbs prefer higher hoop pressure; ventral waist and neck prefer much less. Divide target pressure by Scale C multipliers to get an arm-equivalent feels-like intensity.
Use Scale C for this formula. Scale A (acuity / detection) is noticeability of seams and ridges. Scale B (pressure-pain threshold) is a safety ceiling — keep it in view for neck / face / underbust.
Related: Pressure targets · Simulating natural rubber sheet in Clo3D · scholarly map Body-region pressure sensitivity
Baseline
| Symbol | Meaning |
|---|---|
| P_target | Laplace contact pressure (kPa) from reduction × gauge × R |
| m_C | Scale C preferred clothing-pressure multiplier; upper arm / forearm = 1.0 |
| P_feels | Arm-equivalent preferred-pressure intensity (kPa) |
Higher m_C (wrist, ankle) → same physical P feels milder vs preference. Lower m_C (ventral waist, neck) → same P feels stronger.
Reference skintight fashion band (t₀ = 0.39 mm, r = 12%, soft G): wall tension T ≈ 81 N/m. Mid-limb R = 10 cm → P_target ≈ 0.81 kPa (“light grip”).
Draft multipliers are bands (±~20–40% individual variation). Not latex-wear validated.
Clo3D sites — skintight fashion band (12%)
| Region | R | P_target (kPa) | m_C mid | P_feels (kPa) | Read |
|---|---|---|---|---|---|
| Mid-limb | 10 cm | 0.81 | 1.00 | 0.81 | Light-grip headline |
| Arm | 5 cm | 1.62 | 1.00 | 1.62 | Firmer — smaller R, same preference |
| Wrist | 3 cm | 2.70 | 1.35 | 2.00 | Raw P high; distal preference softens vs arm |
| Waist (ventral) | 12 cm | 0.68 | 0.50 | 1.36 | Absolute P below mid-limb; feels above light grip |
Wrist m_C: mid of distal-arm band 1.2–1.5. Waist m_C: mid of abdomen / waist midline 0.4–0.6.
Equal-% partial cancelation
At the same reduction % (shared wall tension T), Laplace P = T/R so smaller R raises physical P. Distal / limb sites usually carry higher m_C, which lowers P_feels relative to raw P. Trunk / abdomen midline often run the opposite way: larger R softens absolute P, but lower m_C pushes P_feels back up.
On these 12% skintight cells, wrist vs ventral waist is the clearest pair: physical P ≈ 4× (2.70 / 0.68), while P_feels ≈ 1.5× (2.00 / 1.36) — partial cancelation, not full equalization.
Caveat: draft m_C; abdomen midline ≠ lateral trunk; same % ≠ same T if panel paths / stretch differ.
Extended regions (proxied)
Clo3D’s pressure matrix only publishes waist / arm / wrist radii. Other garment regions reuse those P_target cells as budgeting stand-ins — not claims that local anatomy matches the Clo3D column.
| Body region | Proxy P_target | m_C mid (band) | P_feels (kPa) | Notes |
|---|---|---|---|---|
| Thigh | Mid-limb 0.81 | 1.00 (0.9–1.1) | 0.81 | Near light-grip arm-equivalent |
| Lower leg / calf | Arm 1.62 | 1.25 (1.1–1.4) | 1.30 | Milder than raw arm P vs preference |
| Lateral trunk | Waist 0.68 | 0.80 (0.7–0.9) | 0.85 | Higher preference than ventral midline |
| Chest / underbust | Waist 0.68 | 0.65 (0.55–0.75) | 1.05 | Cap at band low end; Scale B sternum low |
| Neck | Arm 1.62* | 0.55 (0.5–0.7) | ~2.95* | Critical for collars/hoods; real R often < 5 cm → higher P |
| Face / forehead | — | 0.50 (0.4–0.6) | — | Not a hoop-cylinder site; Scale B / airway |
*Neck uses arm P as a floor-of-caution stand-in only.
Does cancelation hold across the body?
Same 12% skintight fashion band (T ≈ 81 N/m). Ratios vs arm (P = 1.62, m_C = 1.0). Proxied rows reuse Clo3D waist / arm / mid-limb P as budgeting stand-ins.
| Site | P (kPa) | P_feels | vs arm P | vs arm feels |
|---|---|---|---|---|
| Mid-limb / thigh | 0.81 | 0.81 | 0.50× | 0.50× |
| Arm | 1.62 | 1.62 | 1.0× | 1.0× |
| Lower leg / calf | 1.62 | 1.30 | 1.0× | 0.80× |
| Wrist | 2.70 | 2.00 | 1.67× | 1.23× |
| Shoulder (waist P) | 0.68 | 0.76 | 0.42× | 0.47× |
| Lateral trunk | 0.68 | 0.85 | 0.42× | 0.52× |
| Chest / underbust | 0.68 | 1.05 | 0.42× | 0.65× |
| Waist (ventral) | 0.68 | 1.36 | 0.42× | 0.84× |
| Neck* | 1.62* | ~2.95* | 1.0×* | ~1.8×* |
*Neck: arm-P stand-in; real neck R often smaller → higher physical P. Face omitted (no hoop P).
Verdict: partial / mixed. Across mapped sites (excluding neck / face), physical P spans about 4× (wrist / waist); P_feels spans about 2.6× (wrist / shoulder) — tighter, but not a tight cluster. Limb vs ventral trunk shows the cancelation pattern (wrist/waist 4× → ~1.5×). Same Clo3D waist P still fans in feel space by m_C (shoulder ~0.76 vs ventral ~1.36). Outliers: neck (proxy R + low m_C), underbust (intermediate, Scale B sternum low), face (no cylinder P).
Interaction with other fit / gauge cells
For any cell in the reduction × site matrix:
Example: body-hug fashion-band waist 0.49 kPa / m_C = 0.50 → P_feels ≈ 0.98 kPa — near light-grip intensity despite a softer fit label.
Example: skintight wrist stays firm in feels-like (~2.0 kPa) even after distal m_C softens raw 2.70 kPa — reduction × small R still dominates.
Example: lowering waist reduction (body tailored 0.29 kPa) with m_C = 0.50 → P_feels ≈ 0.58 kPa — below the mid-limb light-grip mark in feel space.
Practical rules
- Pick P_target from pressure targets for the Clo3D site (or proxy).
- Divide by Scale C m_C for that garment region.
- Compare P_feels to mid-limb light grip ~0.8 kPa and arm skintight ~1.6 kPa as intensity landmarks.
- For neck / face / underbust / ventral waist, use the low end of the m_C band and re-check Scale B (body-region map).
- Do not use Scale A multipliers in the feels-like formula.
- Log wear tests; revise when latex-specific data exist.
Physiological safety (airway, respiration, vessels) can diverge from “feels fine” — textile clothing-pressure work stresses autonomic/physiological checks, not comfort scores alone.
Deep dive: Why Scale C only in the formula
Scale A answers noticeability (seam/ridge). Scale B is a pain ceiling. Preferred clothing pressure (Scale C) is the construct that ranks “how hard is acceptable here” for hoop compression. Dividing Laplace P by m_C is a planning synthesis — not a Mitsuno or DFNS result. See Body-region pressure sensitivity.