emission.declaration

ISO 4871:1996 declaration of noise emission values of machinery and equipment.

ISO 4871 is the standardised noise-emission declaration: the information a manufacturer or supplier states in technical documents about the airborne noise emitted by a machine (clause 3.13). It does not measure anything itself; it prescribes which quantities are declared, in which of two alternative forms, and how a declared value is verified (clauses 4 to 6).

The quantities are the A-weighted sound power level L_WA (the preferred and basic quantity, ISO 4871 Note 17) and, optionally, the A-weighted emission sound pressure level L_pA at a work station (clause 3.11). Each is declared in one of two forms selected by the relevant noise test code (clause 4):

• the dual-number form (clause 3.16): a measured noise emission value L and its associated uncertainty K, stated together but separately, both rounded to the nearest decibel; and
• the single-number form (clause 3.15): the derived declared value L_d, the sum L + K of the unrounded quantities rounded once to the nearest decibel, an upper limit which values from repeated measurements are unlikely to exceed at the stated confidence level.

K combines the measurement uncertainty (reproducibility) and, for a batch, the production spread (clauses 3.20 to 3.24; K = 1,645 sigma_R for a single machine, Annex A.2.2). Verification (clause 6) compares a verification measurement L_1 against the declared form: for a single machine the combined form is verified when L_1 <= L_d and the dual-number form when L_1 <= (L + K), the sum of the separately rounded declared values (clause 6.2).

This module models a declaration as NoiseEmissionDeclaration, a set of OperatingModeDeclaration values (one per operating mode, clause 4), and renders it as an ISO 4871 declaration fiche through .report. A declaration is most often built from a measured sound power via declare.

Auto-generated from the source docstrings by scripts/generate_api_docs.py (make api-docs). Do not edit by hand.

NoiseEmissionDeclaration

NoiseEmissionDeclaration(
    modes: Sequence[OperatingModeDeclaration],
    machine: str | None = None,
    operating_conditions: str | None = None,
    noise_test_code: str | None = None,
    basic_standards: Sequence[str] = ...,
    form: DeclarationForm = 'dual-number',
)

An ISO 4871:1996 declaration of noise emission values (clauses 4 to 6).

A declaration is one or more OperatingModeDeclaration values (one per operating mode, clause 4) plus the accompanying information required by clause 5: identification of the machinery (clause 5 a), the noise test code and basic standards used (clause 5 b) and the operating conditions (clause 5 c). report renders it as a one-page ISO 4871 declaration fiche.

Attributes

Name	Description
modes	One or more per-operating-mode declarations. A sequence is accepted and stored as a tuple.
machine	Machine identification (model number and other identifying information, clause 5 a).
operating_conditions	Operating and mounting conditions the values refer to (clause 5 c), e.g. "50 Hz, 230 V, rated load".
noise_test_code	The noise test code the values were determined to (clause 5 b), e.g. an ISO family-specific test code; None when none exists.
basic_standards	The basic noise-emission standard(s) used to obtain the values (clause 5 b), e.g. ("ISO 3744",). A single string is accepted and wrapped in a one-tuple.
form	Which declaration form the fiche presents, "dual-number" (default, clause 3.16: L and K separately) or "single-number" (clause 3.15: the derived L_d = L + K).

Raises

Exception	When
ValueError	If no operating mode is given or form is unknown.

NoiseEmissionDeclaration.report()

NoiseEmissionDeclaration.report(
    path: str,
    *,
    metadata: ReportMetadata | None = None,
    engine: str = 'reportlab',
    verbose: bool = False,
    language: str = 'en',
) -> str

Render an ISO 4871 noise-emission declaration fiche to a PDF.

Writes a one-page declaration data sheet: the standard-basis line (ISO 4871:1996 and the cited basic emission standard), the machine identification and operating conditions, the declared dual- or single-number table across the operating-mode columns following the ISO 4871 Annex B layouts (L_WA and K_WA for the dual-number form, the derived L_WAd = L_WA + K_WA for the single-number form, plus the emission sound pressure level when declared), the noise-test-code and basic-standards footnote, a verification verdict table when a verification measurement is supplied (clause 6.2, against L_WAd for the single-number form or the separately rounded L_WA + K_WA for the dual-number form), and the footer identity/disclaimer block.

Parameters

Name	Description
path	Destination path of the PDF file.
metadata	Optional ReportMetadata supplying the laboratory identity (footer) and, through measurement_standard, the basic emission standard shown in the standard-basis line when basic_standards is empty.
engine	Rendering back end; only "reportlab" is supported.
verbose	Accepted for a uniform .report() signature; the declaration fiche has a single table layout, so it has no effect.
language	Fiche language: "en" (default, English) or "es" (Spanish, with a comma decimal separator).

Returns: The written path as a str.

Raises

Exception	When
ValueError	If engine is not "reportlab" or language is unknown.
ImportError	If reportlab is not installed (pip install phonometry[report]).

OperatingModeDeclaration

OperatingModeDeclaration(
    mode: str,
    sound_power_level: float,
    sound_power_uncertainty: float,
    emission_pressure_level: float | None = None,
    emission_pressure_uncertainty: float | None = None,
    verification_level: float | None = None,
)

Declared dual-number noise-emission values for one operating mode.

Holds the measured A-weighted sound power level L_WA and its uncertainty K_WA (ISO 4871 clause 3.16), and optionally the A-weighted emission sound pressure level L_pA at a work station with its uncertainty K_pA (clause 3.11). The derived declared single-number values follow from L_d = L + K (clause 3.15), the sum rounded to the nearest decibel. When a verification measurement L_1 (an A-weighted sound power level determined for verification, clause 6) is supplied, verified applies the single-machine criterion of clause 6.2 for the combined form (verified when L_1 <= L_WAd) and verified_dual the dual-number one (verified when L_1 <= round(L_WA) + round(K_WA)).

Attributes

Name	Description
mode	Operating-mode label printed as the table column header (e.g. "Operating mode 1"); it identifies the operating mode of clause 5 c.
sound_power_level	Measured mean A-weighted sound power level L_WA, in decibels re 1 pW.
sound_power_uncertainty	Uncertainty K_WA of the sound power level, in decibels (finite and non-negative).
emission_pressure_level	A-weighted emission sound pressure level L_pA at the work station, in decibels re 20 uPa; None when only the sound power level is declared.
emission_pressure_uncertainty	Uncertainty K_pA of the emission sound pressure level, in decibels; required when emission_pressure_level is given and forbidden otherwise.
verification_level	A verification measurement L_1 of the A-weighted sound power level (clause 6), in decibels; None when the mode is not verified.

Raises

Exception	When
ValueError	If a level is not finite, an uncertainty is not finite and non-negative, or only one member of the emission-pressure pair is given.

OperatingModeDeclaration.declared_emission_pressure_level

property

Declared single-number emission pressure level L_pAd = L_pA + K_pA.

The sum L_pA + K_pA rounded once to the nearest decibel (clause 3.15); None when no emission sound pressure level is declared for the mode.

OperatingModeDeclaration.declared_sound_power_level

property

Declared single-number sound power level L_WAd = L_WA + K_WA (3.15).

Clause 3.15 defines the declared value as the sum of the measured value and its uncertainty, rounded to the nearest decibel: the sum is formed from the unrounded quantities (clause 3.12) and rounded once, not assembled from the separately rounded dual-number values (3.16).

OperatingModeDeclaration.dual_number_verification_limit

property

Dual-number verification reference (L + K) (clauses 3.16, 6.2).

The dual-number form declares L and K each rounded to the nearest decibel (clause 3.16), and clause 6.2 verifies that form against their sum (L + K); the limit is therefore round(L_WA) + round(K_WA) — not the single-number L_WAd (the unrounded sum rounded once), which can differ by one decibel.

OperatingModeDeclaration.verified

property

Single-machine verification verdict, combined form (clause 6.2).

True when the verification measurement L_1 does not exceed the combined (single-number) declared value L_WAd (L_1 <= L_WAd), False otherwise, and None when no verification measurement is supplied. For a dual-number declaration use verified_dual, which compares against the separately rounded L + K.

OperatingModeDeclaration.verified_dual

property

Single-machine verification verdict, dual-number form (clause 6.2).

True when the verification measurement L_1 does not exceed the sum of the separately rounded declared values (L_1 <= round(L_WA) + round(K_WA), clauses 3.16 and 6.2), False otherwise, and None when no verification measurement is supplied.