STC and NIC Metric Classifier
Classify a caller-supplied ASTM or ISO airborne-sound record as laboratory STC, field NIC, apparent ASTC, or the corresponding distinct rating without equating the metrics.
Description
Laboratory transmission and field room-isolation ratings describe different test conditions and paths.
Laboratory transmission and field room-isolation ratings describe different test conditions and paths. Matching the recorded method and metric prevents false equivalence.1
Classify a caller-supplied ASTM or ISO airborne-sound record as laboratory STC, field NIC, apparent ASTC, or the corresponding distinct rating without equating the metrics.
When to use STC and NIC Metric Classifier
Use this tool to classify a caller-supplied ASTM or ISO airborne-sound record as laboratory STC, field NIC, apparent ASTC, or the corresponding distinct rating without equating the metrics.
Choose a supported reference topic, run an input-free reference with an empty object, or prepare the measured values and caller-supplied test records requested. Keep acoustic metrics, frequency, units and test conditions consistent.
How to use STC and NIC Metric Classifier and understand its results
- Choose a supported reference topic, run an input-free reference with an empty object, or prepare the measured values and caller-supplied test records requested. Keep acoustic metrics, frequency, units and test conditions consistent.
- Enter queryRecordId, records using the field table and calculation rules, then run the tool.
- Read caveat, classification, interpretation, selectedRecord. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| queryRecordId | Sound-rating record identifier | string; minimum length: 1 | Required |
| records | Sound-rating records | list of object; minimum entries: 1; maximum entries: 200 | Required |
| records[].environment | Field in records record | string; one of "field", "laboratory" | Required in each record |
| records[].flankingPathsIncluded | Field in records record | boolean | Required in each record |
| records[].metric | Field in records record | string; one of "ASTC", "D_nT,w", "FSTC", "NIC", "NNIC", "Rw", "STC" | Required in each record |
| records[].rating | Field in records record | number; minimum: 0 | Required in each record |
| records[].recordId | Field in records record | string; minimum length: 1 | Required in each record |
| records[].source | Field in records record | string; minimum length: 1 | Required in each record |
| records[].testMethod | Field in records record | string; one of "ASTM E336", "ASTM E596", "ASTM E90", "ISO 10140-2", "ISO 16283-1" | Required in each record |
| records[].testReference | Field in records record | string; minimum length: 1 | Required in each record |
Supply 1–200 records with unique raw IDs, source/reference and nonnegative rating, then query an exact ID. Require E90/STC, E596/NIC or ISO10140-2/Rw to be laboratory without flanking; ISO16283-1/D_nT,w field with flanking; E336 field ASTC/NIC/NNIC with flanking or FSTC without. Return selected record, classification, interpretation and caveat.
classify selected compatible method/metric/environment/flanking combination Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| caveat | caveat | string |
| classification | Rating distinction | string; one of "field-apparent-transmission", "field-iso", "field-reduced-flanking", "field-room-isolation", "laboratory-direct-transmission" |
| interpretation | interpretation | string |
| selectedRecord | Selected sound-rating record | object |
| selectedRecord.environment | Field in selectedRecord | string; one of "field", "laboratory" |
| selectedRecord.flankingPathsIncluded | Field in selectedRecord | boolean |
| selectedRecord.metric | Field in selectedRecord | string; one of "ASTC", "D_nT,w", "FSTC", "NIC", "NNIC", "Rw", "STC" |
| selectedRecord.rating | Field in selectedRecord | number; minimum: 0 |
| selectedRecord.recordId | Field in selectedRecord | string; minimum length: 1 |
| selectedRecord.source | Field in selectedRecord | string; minimum length: 1 |
| selectedRecord.testMethod | Field in selectedRecord | string; one of "ASTM E336", "ASTM E596", "ASTM E90", "ISO 10140-2", "ISO 16283-1" |
| selectedRecord.testReference | Field in selectedRecord | string; minimum length: 1 |
{
"input": {
"queryRecordId": "caller-lab-stc",
"records": [
{
"environment": "laboratory",
"flankingPathsIncluded": false,
"metric": "STC",
"rating": 53,
"recordId": "caller-lab-stc",
"source": "Illustrative caller-supplied ASTM E90/E413 laboratory record",
"testMethod": "ASTM E90",
"testReference": "LAB-2026-001"
},
{
"environment": "field",
"flankingPathsIncluded": true,
"metric": "NIC",
"rating": 47,
"recordId": "caller-field-nic",
"source": "Illustrative caller-supplied ASTM E336/E413 field record",
"testMethod": "ASTM E336",
"testReference": "FIELD-2026-001"
}
]
},
"output": {
"caveat": "STC, NIC, NNIC, ASTC, FSTC, Rw, and DnT,w are distinct metrics. ASTM E90 laboratory STC suppresses significant flanking paths and is not a field prediction; ASTM E336 field ratings include room and indirect-path effects according to the selected metric. Do not substitute one rating for another in a code or specification without the applicable test and reporting conditions.",
"classification": "laboratory-direct-transmission",
"interpretation": "ASTM E90 with ASTM E413 produces a laboratory STC for the specimen under controlled direct-path conditions.",
"selectedRecord": {
"environment": "laboratory",
"flankingPathsIncluded": false,
"metric": "STC",
"rating": 53,
"recordId": "caller-lab-stc",
"source": "Illustrative caller-supplied ASTM E90/E413 laboratory record",
"testMethod": "ASTM E90",
"testReference": "LAB-2026-001"
}
}
}Limitations and assumptions
All records are validated before selection. E596 is grouped under laboratory-direct-transmission but its enclosure NIC is distinct from assembly STC. No rating is computed, source authenticated or metric converted.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Stud Wall STC Comparison: Compare a caller-supplied single-stud and double-stud laboratory STC pair, return the signed point difference, and preserve each test reference without treating the result as a universal construction rule. For a complementary task, use OITC Reference: Return the scope and traffic-noise relevance of Outdoor-Indoor Transmission Class.
References
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STC and NIC Metric Classifier — tool.io
Similar or alternative tools
- Stud Wall STC Comparison
Compare a caller-supplied single-stud and double-stud laboratory STC pair, return the signed point difference, and preserve each test reference without treating the result as a universal construction rule.
- OITC Reference
Return the scope and traffic-noise relevance of Outdoor-Indoor Transmission Class.