Balanced Noise Criterion Reference
Explain the revised balanced-noise-criterion method and its relationship to other room-noise ratings.
Description
NCB was developed to rate broadband room noise while identifying spectra with excessive low- or high-frequency content.
NCB was developed to rate broadband room noise while identifying spectra with excessive low- or high-frequency content. This reference explains the selected concept and the evidence needed to interpret it.1
The returned values include Source, Statement, Topic. The How section below explains the calculation, input rules and interpretation.
When to use Balanced Noise Criterion Reference
Use Balanced Noise Criterion Reference when you need to evaluate the supplied records under the calculation and evidence rules below. NC, NCB, RC, and dBA use different procedures and must not be converted by a universal fixed offset. This is an introductory excerpt, not the complete standard, a current compliance check or a project-specific calculation.
Choose the measured quantities, units, weighting and measurement basis before entering values. For a reference, select the exact topic. For a catalog lookup, prepare complete source-backed records; for a screen, select an applicable caller limit.
How to use Balanced Noise Criterion Reference and understand its results
- Choose the measured quantities, units, weighting and measurement basis before entering values. For a reference, select the exact topic. For a catalog lookup, prepare complete source-backed records; for a screen, select an applicable caller limit.
- Enter topic using the field table and calculation rules, then run the tool.
- Read source, statement, topic. 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 |
|---|---|---|---|
| topic | Reference topic to return. | string; one of "purpose", "descriptor", "caution" | Required |
Choose one of the exact topic values in the table. The tool indexes a fixed, locally embedded reference entry and returns its source label, statement and unchanged topic. It does not fetch the source or update the wording. Topic meanings and all returned entries are shown below.
| Selection | Returned reference entry |
|---|---|
| purpose | source: ANSI/ASA S12.2 and Beranek room-noise literature; statement: NCB was developed to rate broadband room noise while identifying spectra with excessive low- or high-frequency content.; topic: purpose |
| descriptor | source: ANSI/ASA S12.2; statement: A complete NCB result includes the rating procedure and any spectral-quality designation rather than only one broadband level.; topic: descriptor |
| caution | source: ANSI/ASA S12.2 and ASHRAE guidance; statement: NC, NCB, RC, and dBA use different procedures and must not be converted by a universal fixed offset.; topic: caution |
selected exact topic → embedded source label, explanatory statement and topic Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| source | Source used for the reference statement. | string |
| statement | Narrow reference statement for the selected topic. | string |
| topic | Selected reference topic. | string; one of "purpose", "descriptor", "caution" |
{
"input": {
"topic": "purpose"
},
"output": {
"source": "ANSI/ASA S12.2 and Beranek room-noise literature",
"statement": "NCB was developed to rate broadband room noise while identifying spectra with excessive low- or high-frequency content.",
"topic": "purpose"
}
}Limitations and assumptions
NC, NCB, RC, and dBA use different procedures and must not be converted by a universal fixed offset. This is an introductory excerpt, not the complete standard, a current compliance check or a project-specific calculation.
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 fields without a declared default, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Classroom Background-Noise Screen: Background noise in an unoccupied furnished classroom affects listening conditions. A measurement should be compared with an explicitly chosen applicable design limit. For a complementary task, use Leaf-Blower Tonality Reference: Blade-pass and engine components can create prominent tones, but tonality must be established from measured spectra using the specified method. This reference explains the selected concept and the evidence needed to interpret it.
References
-
Balanced Noise Criterion Reference — tool.io
Similar or alternative tools
- Classroom Background-Noise Screen
Background noise in an unoccupied furnished classroom affects listening conditions. A measurement should be compared with an explicitly chosen applicable design limit.
- Leaf-Blower Tonality Reference
Blade-pass and engine components can create prominent tones, but tonality must be established from measured spectra using the specified method. This reference explains the selected concept and the evidence needed to interpret it.