GHS Mixture Hazard Classification Calculator

A Streamlit-based calculator that classifies chemical mixtures using official GHS cut-off concentrations, producing a hazard profile based on ingredient hazard data.

What It Does

Enter a list of chemical ingredients and their contributions (by percentage or moles), and this app automatically:

• Applies GHS classification rules for health hazards
• Calculates applicable hazard classes such as:
  • Acute Toxicity
  • Skin Corrosion/Irritation
  • Carcinogenicity
  • And more
• Outputs a complete hazard profile, including:
  • Hazard class names
  • GHS pictograms
  • Signal words (e.g., Danger, Warning)
  • H-statements (e.g., H301: Toxic if swallowed)
• Allows printing to PDF for documentation or SDS use

Built With

• Python
• Streamlit (web app framework)

Features

• Mass or concentration and molar mass based input calculated automatically to w/w%
• Fully compliant with GHS health hazard thresholds
• Takes most careful approach, always choosing lowest possible cut-off concentration limit
• Automatically composes hazard pictograms and signal words
• Clean, printable summary page
• No internet or API dependency — runs entirely locally
• About page detailing calculations

Use Cases

• SDS authoring and compliance checks
• Laboratory safety and chemical mixture assessments
• Regulatory prep for REACH, CLP, OSHA HazCom
• Teaching and training in chemical safety

Note: This calculator applies only the GHS cut-off concentration thresholds to classify mixture hazards.
It does not incorporate experimental toxicity data or in-depth risk assessment.
Use this tool as a guidance aid and not as definitive evidence for regulatory or safety decisions.
Always consult qualified safety professionals and official testing results when necessary.

Getting Started

Clone and launch the application.

git clone https://github.com/henryteahan/hazard-classifier.git
cd hazard-classifier
conda create -n hazardclassifier
conda activate hazardclassifier
pip install -r requirements.txt
streamlit run App.py

Integration with On-Site Registry Checks

This calculator is designed to be easily integrated with on-site chemical registry systems or compliance workflows.

While proprietary registry documents cannot be shared publicly, the app's modular architecture allows seamless extension or API hooking to:

• Automatically fetch ingredient details from internal chemical databases
• Perform batch hazard classification against local chemical inventories
• Streamline SDS creation and regulatory audits on-site

To facilitate this, example integration workflows and scripts can be provided privately upon request to henry@teahan.dk.

Disclaimer

This calculator performs hazard classification exclusively using GHS cut-off concentration thresholds as defined by international regulations.

It does not use empirical toxicity testing or replace comprehensive chemical risk assessments.

The results are intended as a guidance tool only. For formal safety evaluations or legal compliance, please refer to certified testing data and consult with chemical safety experts.