Research Toolkit Biomechanical Tolerance Dataset and Computational Model for Safe Hair Extension Architecture

Author: Yuliia CowanVersion: 1.0License: Creative Commons Attribution 4.0 International (CC-BY 4.0)Related Publication: HairHarmony Balance: Innovative System for Safe and Aesthetic Hair Extensions (Monograph) 1. Overview This dataset and the accompanying computational model (HairHarmony_Biomechanical_Model.ipynb) provide a standardized, evidence-based framework for calculating safe donor hair loads during spatial extension procedures. The data synthesizes over 100 clinical archetypes, evaluating the interplay between native hair morphology, chemical degradation, and anatomical scalp zones to prevent iatrogenic traction alopecia. 2. Methodology of Data Synthesis The tolerance matrix was generated using a deterministic biomechanical algorithm (the "CEMS Method"). Instead of relying on subjective stylist intuition, the load limits are calculated by integrating: Base Carrying Capacity: Derived from the average shaft diameter and intact cross-sectional area of the native hair. Young's Modulus Reduction Factor: A penalizing coefficient reflecting the loss of tensile strength and protein matrix integrity due to oxidative cosmetic processing (e.g., bleaching). Anatomical Tension Mapping: Scalp zones are weighted according to their recognized vulnerability to traction (e.g., the marginal hairline tolerates significantly less sustained load than the occipital zone). Clinical Modifiers: Variables such as active erythema, pre-traction markers, and poor aftercare compliance serve as absolute or relative contraindications. 3. Toolkit Contents (File Structure) This research toolkit repository contains the following interconnected files: Biomechanics_Tolerance_Dataset.csv: The core dataset containing simulated clinical archetypes mapping client biological parameters to maximum safe load limits and recommended attachment hardware. HairHarmony_Biomechanical_Model.ipynb: An interactive Jupyter Notebook providing a lookup interface and implementing the deterministic computational formula for safety parameters. CEMS_Clinical_Assessment_Protocol.pdf: The standardized pre-installation diagnostic protocol form used by practitioners to record client variables. dataset_visualisation.jpg: High-resolution data visualization charting capsule weight distributions across clinical protocols. 4. Data Dictionary (Column Descriptions) The dataset file Biomechanics_Tolerance_Dataset.csv contains the following variables: Input Variables (Biological & Clinical Assessment) Profile_ID (String): Unique identifier for the simulated clinical archetype (e.g., HH-001). Hair_Thickness (Categorical): Visual and tactile evaluation of the native hair shaft (Fine, Medium, Coarse). Diameter_um_range (String): The estimated micrometer range corresponding to the thickness category (e.g., 35-45, 60-80, 90-110+). Chemical_History (Categorical): The cosmetic history of the hair (Virgin, Tinted, Bleached, Compromised). Degradation_pct (Integer): The estimated percentage of structural degradation/elasticity loss based on the chemical history. Scalp_Zone (Categorical): The targeted anatomical area (Supportive [Crown/Occipital], Conditional [Mid-temporal], High-Risk [Marginal Hairline/Nape]). Apparent_Density_fol_cm2 (Integer): Estimated follicular density in the target zone. Scalp_Condition (Categorical): Trichoscopic health of the scalp (Healthy, Erythema, Pre-Traction Markers). Aftercare_Compliance (Categorical): Expected client adherence to low-friction maintenance protocols (High, Low). Output Variables (Computational Directives) Max_Capsule_Weight_g (Float): Target Variable. The absolute maximum safe weight (in grams) for a single donor attachment in the specified zone. Recommended_Fixation (Categorical): The suggested attachment hardware size based on the calculated weight limit (Standard, Micro, Nano, Ultra-Nano, None). Wear_Cycle_weeks (Integer): The maximum recommended duration (in weeks) before the extensions must be removed or corrected to prevent mechanical overload. Strand_Count_per_zone (Integer): The maximum number of attachments allowed within the evaluated anatomical zone to maintain spatial proportion. Clinical_Action (Categorical): The mandated operational protocol (e.g., Standard Single-Stage, Staged Extension, Refusal (Alternative Therapy)). Refusal_Flag (Binary/Integer): Machine-learning ready boolean flag. 1 indicates the procedure must be refused due to extreme biomechanical risk; 0 indicates the procedure may proceed under the specified limits. Notes (String): Contextual clinical rationale for the specific algorithmic output. 5. Usage and Integration This dataset is designed to be used in conjunction with the CEMS Clinical Assessment Protocol. Practitioners can map their real-world client variables to this dataset to find the exact, scientifically backed weight limits and protocols. Data scientists and dermatological researchers can utilize the Refusal_Flag and Max_Capsule_Weight_g variables to train predictive models for preventing traction-induced hair loss in cosmetology. 6. Ethical Considerations and Limitations The Ethics of Refusal: This dataset explicitly models scenarios where aesthetic enhancement must be denied to protect client health. The Refusal (Alternative Therapy) directive and Refusal_Flag are core functional features—not bugs—designed to strictly enforce the principle of non-maleficence in clinical trichology. Limitations: The values in this dataset represent computationally modeled clinical archetypes generated using established trichological and biomechanical metrics, rather than raw empirical data from active human trials. While serving as a robust predictive baseline, they do not replace live trichoscopic monitoring. Individual biological anomalies (e.g., severe nutritional deficits or hormonal fluctuations) may necessitate mid-cycle adjustments. 7. Citation Request If you utilize this dataset, methodology, or computational model in academic research, software development, or commercial educational materials, please cite it as follows: Cowan, Y. (2026). Research Toolkit: Biomechanical Tolerance Dataset and Computational Model for Safe Hair Extension Architecture (HairHarmony Balance) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21037485