Overview
ISO 10054:1998 specifies the characteristics and verification procedures for filter-type smokemeters used to measure soot (blackening) in the exhaust gas of reciprocating internal combustion compression‑ignition (diesel) engines operating under steady‑state conditions. The standard defines the measurement principle (optical blackening of a filter), the filter smoke number (FSN) metric, reference conditions (100 kPa, 298 K), and required design, sampling and verification criteria for consistent, comparable smoke measurement.
Key topics and technical requirements
- Measurement principle: soot in an exhaust gas column is collected on a cellulose filter; degree of blackening is quantified by optical reflectance versus a clean filter and expressed as the Filter Smoke Number (FSN).
- Probe & sampling system: probe must take a representative sample (near exhaust centre) with minimal back pressure; mean gas velocity during sampling must be sufficient to avoid soot deposition (preventing biased results).
- Dead volume & suction volume: dead volume (probe to filter) shall not exceed 15% of nominal suction volume for typical probes (up to 40% allowed for special probes with manufacturer correction data). Suction time definitions and limits are provided for piston and constant‑delivery pumps.
- Filter clamping and area: effective filter area is defined by clamping device; inner diameter of upstream clamp must be between 15 mm and 35 mm to standardize sampled area and blackening uniformity.
- Filter material: natural cellulose filters without binders/resins (examples given: Schleicher & Schüll No. 604 LB, Whatman No. 4) and unexposed filter reflectance requirements are specified.
- Reflectometer & evaluation: reflectance measured per referenced optical standards (e.g., CIE 38, DIN/CIE standards); the reflectometer reading across a representative portion of the effective area must meet accuracy criteria (e.g., within specified FSN tolerance).
- Leakage, temperature & pressure: static and dynamic leakage limits are specified (leak influences on effective length and sampled mass must be controlled); manufacturer must state operating pressure/temperature ranges and corrections to reference conditions.
- Verification & calibration: procedures for leak checks, suction volume verification, calibration screens, reflectometer accuracy and statistical methods are described (Annex A gives equipment and test procedures).
Applications and users
ISO 10054:1998 is used by:
- Engine test laboratories and R&D facilities conducting steady‑state diesel smoke measurements
- Smokemeter manufacturers (design, calibration and type verification)
- Vehicle and engine manufacturers for emissions control and quality assurance
- Regulatory and certification bodies that adopt standardized smoke measurement protocols
This standard is not intended for transient condition testing or aircraft engines; comparisons across instrument types require identical sampling conditions.
Related standards
ISO 10054 references optical/photometric and testing standards (e.g., CIE 38, DIN 5036 series) and complements engine test standards that define steady‑state test conditions and reference pressures/temperatures.