Directive 2005/55/EC of the European Parliament and of the Council (repealed)Show full title

5. DETERMINATION OF SMOKE

This section provides specifications for the required and optional test equipment to be used for the ELR test. The smoke shall be measured with an opacimeter having an opacity and a light absorption coefficient readout mode. The opacity readout mode shall only be used for calibration and checking of the opacimeter. The smoke values of the test cycle shall be measured in the light absorption coefficient readout mode.

5.1. General requirements

The ELR requires the use of a smoke measurement and data processing system which includes three functional units. These units may be integrated into a single component or provided as a system of interconnected components. The three functional units are:

• an opacimeter meeting the specifications of Annex V, Section 3,

• a data processing unit capable of performing the functions described in Annex III, Appendix 1, Section 6,

• a printer and/or electronic storage medium to record and output the required smoke values specified in Annex III, Appendix 1, Section 6.3.

5.2. Specific requirements

5.2.1. Linearity

The linearity shall be within ± 2 % opacity.

5.2.2. Zero drift

The zero drift during a one hour period shall not exceed ± 1 % opacity.

5.2.3. Opacimeter display and range

For display in opacity, the range shall be 0-100 % opacity, and the readability 0,1 % opacity. For display in light absorption coefficient, the range shall be 0-30 m^-1 light absorption coefficient, and the readability 0,01 m^-1 light absorption coefficient.

5.2.4. Instrument response time

The physical response time of the opacimeter shall not exceed 0,2 s. The physical response time is the difference between the times when the output of a rapid response receiver reaches 10 and 90 % of the full deviation when the opacity of the gas being measured is changed in less than 0,1 s.

The electrical response time of the opacimeter shall not exceed 0,05 s. The electrical response time is the difference between the times when the opacimeter output reaches 10 and 90 % of the full scale when the light source is interrupted or completely extinguished in less than 0,01 s.

5.2.5. Neutral density filters

Any neutral density filter used in conjunction with opacimeter calibration, linearity measurements, or setting span shall have its value known to within 1,0 % opacity. The filter's nominal value must be checked for accuracy at least yearly using a reference traceable to a national or international standard.

Neutral density filters are precision devices and can easily be damaged during use. Handling should be minimised and, when required, should be done with care to avoid scratching or soiling of the filter.