Hazard Levels (1–5)
Understanding the 5-level hazard classification system used to indicate overall chemical danger in your library.
NextSDS rates a product's intrinsic hazards based on the classification in section 2 of the SDS (GHS/CLP). The hazard is expressed using five hazard levels where the most hazardous products score 5 and the least hazardous score 1.
| Level | Label | Description |
|---|
| 5 | Extreme | Highest severity across one or more categories. Severe or life-threatening hazards present. |
| 4 | High | Serious risks in one or more categories. Significant health, environmental, or safety hazards. |
| 3 | Moderate | Moderate risks present. Noticeable health, environmental, or safety concerns requiring precautions. |
| 2 | Low | Minor risks present in one or more categories. Low severity effects possible. |
| 1 | Minimal | Negligible risk across health, environment, and safety. Safe under normal use. |
The overall level is the maximum of three sub-scores: Health, Environmental, and Safety. See detailed H-code mapping for the complete list of hazard statements per level.
| Category | Description |
|---|
| Health | Fatal if swallowed, inhaled, or upon skin contact. May cause cancer, genetic defects, or damage to fertility. |
| Environmental | Very toxic to aquatic life with long-lasting effects. Accumulates in nature and organisms. Ozone depletion and widespread water contamination. |
| Safety | Explosive, even without air. Severe fires, blast hazards, or violent reactions. |
| Category | Description |
|---|
| Health | Toxic via all routes. Serious burns and eye damage. Allergic reactions. Organ damage or long-term health issues. |
| Environmental | Very toxic or toxic to aquatic life and some land species. Suspected endocrine disruption. |
| Safety | Extremely flammable gases, liquids, and aerosols. Explosive when heated. Violent reactions with air, water, or chemicals. |
| Category | Description |
|---|
| Health | Harmful via all routes. Eye irritation and mild organ damage. Allergic reactions possible. |
| Environmental | Toxic or harmful to aquatic life with possible long-lasting effects. |
| Safety | Flammable gases, liquids, and solids. Pressurised gases. Self-ignition or dangerous reaction with water possible. |
| Category | Description |
|---|
| Health | Mild skin or eye irritation. Dizziness, drowsiness, or respiratory irritation. Risks from repeated exposure. |
| Environmental | Harmful to aquatic life, but less severe than higher levels. |
| Safety | Flammable liquids and gases, but generally less intense hazards. |
| Category | Description |
|---|
| Health | Mild skin irritation in rare cases. Safe if handled properly. |
| Environmental | No significant environmental impact. |
| Safety | No special safety hazards under normal conditions. |
Each hazard statement (H-code) found in section 2 of the SDS is mapped to a level across three risk categories:
- Health — acute toxicity, CMR properties, organ damage, sensitisation
- Environmental — aquatic toxicity, persistence, ozone depletion
- Safety — flammability, explosiveness, oxidising properties
The product's overall level is the maximum across all three categories. The individual sub-scores for Health, Environmental, and Safety are visible in the tooltip in the library.
- Library table — as a colour-coded indicator in the "Hazard Level" column
- Hover tooltip — shows the overall level plus Health, Environmental, and Safety sub-scores