Use the U.S. AQI category ranges
See this course’s project requirements
An air-quality interpretation card with pollutant/time metadata, AQI categories, official guidance and revised activity choices for fictional users.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- Separate weather, appearance and pollutant information.
- Compare place, pollutant, time and report type.
- Classify all supplied category boundaries.
- Match the particle guide to fictional group/activity facts.
- Compare indoor alternatives with scope and heat/source limits.
- Document a changed report and revised decision without personal health data.
Review and revise
Use these criteria to check your work and choose what to improve.
- Method: applies the course-specific rules to the supplied cases with visible intermediate work.
- Accuracy: results agree with the stated facts, units, boundaries and independent checks.
- Reasoning: explains why the result follows and identifies a limitation or unresolved question.
- Transfer: completes changed cases and revises the final project when a relevant assumption changes.
Want more background?
The idea in everyday life
Fictional index cards:49,100,101,150,151,301. These are AQI values already supplied, not raw concentration readings or current outdoor conditions.
For the U.S. AQI ranges used here:0–50 Good; 51–100 Moderate; 101–150 Unhealthy for Sensitive Groups; 151–200 Unhealthy; 201–300 Very Unhealthy; 301 and higher Hazardous. The labels communicate graded concern. Boundaries are inclusive as written; 100 and 101 belong to different ranges. Do not convert a pollutant concentration directly using these index ranges.
Use the U.S. AQI category ranges — worked practice
For the U.S. AQI ranges used here:0–50 Good; 51–100 Moderate; 101–150 Unhealthy for Sensitive Groups; 151–200 Unhealthy; 201–300 Very Unhealthy; 301 and higher Hazardous. The labels communicate graded concern. Boundaries are inclusive as written; 100 and 101 belong to different ranges. Do not convert a pollutant concentration directly using these index ranges.
Fictional index cards:49,100,101,150,151,301. These are AQI values already supplied, not raw concentration readings or current outdoor conditions.
1. 1. Assign
Classify 49 and 100.
You should see: 49 Good; 100 Moderate.
2. 2. Boundary
Classify 101 and 150.
You should see: Both Unhealthy for Sensitive Groups.
3. 3. Higher
Classify 151 and 301.
You should see: 151 Unhealthy; 301 Hazardous.
4. 4. Limit
Explain why a concentration number cannot simply use this table.
You should see: Concentration units and pollutant-specific calculations differ; these ranges apply to index values.
What to finish
An AQI category card with six examples and a units warning.
Watch for this
The table expects an AQI index value, not a concentration. Pollutant-specific methods are needed before applying an index category.
How can I tell I understand it?
Classify a changed boundary value without shifting the range endpoints.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
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Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
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Source & access notes · checked 2026-10-01
Web open/search showed the official page, its topic heading and relevant concept description. This is a content/source check, not a provider endorsement.
Access: Official page retrieved with the web reader on 2026-10-01; interactive tools and videos were not certified by retrieval.
Reuse: Original fictional teaching cases, calculations, questions and examples; link and short factual paraphrase only. No copied source exercises or illustrations.
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