BS EN 15892-2011 pdf download.Railway applications – Noise Emission – Measurement of noise Inside driver’s caps.
6.1.3 Track conditions No track condition.
6.2 Test procedure
The stationary measurements require the noise level in the vicinity of the drivers ears to be quantified when the external warning horn is sounded.
When the cab contains more than one set of complete driving controls, the test shall be carried out at each of these positions. This is not necessary at auxiliary driving positions where a full set of controls is not present. When the external warning horn has more than one operating control, the test shall be carried out using each of these controls.
If the vehicle or multiple unit has two cabs and is symmetrical about its longitudinal centre, it is only necessary to carry out the full test within one cab provided the horn configuration and installation is identical for both cabs, If this is not the case, the tests shall be carried out In both cabs and the higher resultant level shall be recorded.
Sound pressure levels shall be measured at the normal operational energy level available on the vehicle. When the external warning horn has two or more tones or chords the following tests shall be carried out for both or all of these. When the acoustic warning has an option for a loud or quiet setting, the loud setting shall be used.
Measurement conditions shall comply with EN 15153-2 for the measurement of horn performances. If the value of LAT measured under these conditions is outside the range specified for this test within EN 15153-2. or if these measured levels before and after the stationary cab noise measurements differ by more than 3 dB, the cab noise results are invalid.
The background noise level within the cab shall be measured and recorded at the beginning and end of the stationary measurement, in terms of over a measurement time interval, T. of 20 s. This measurement shall be obtained at the same position on both occasions, and that position is to be chosen from one of the available eight locations as defined below.
The measurement shall be carried out at eight evenly spaced microphone positions in a horizontal plane at the height of a seated driver’s ears, at a radius of 25 cm, while the external warning horn is sounding. The position of the seated driver’s ears, if not defined elsewhere, shall be taken at 080 m ± 0,05 m vertically above the centroid of the unloaded seat surface. If the seat height Is adjustable, this adjustment shall be set at midrange. The height of this nominal position for the driver’s seat above the floor shall be recorded.
NOTE 1 In case a headrest present hindrance for mounting the microphones, it is pern’iissibe to remove the headrest or to use a measurement height as close as possible to the specified measurement height.
If not defined elsewhere, the level of the driver’s ear for standing operation shall be taken as 1,6 m above the floor.
Where one or more of the required eight microphone positions is either not possible to realise because of the presence of structural elements, or where it is within 20 cm of an acoustically-reflective surface, a measurement shall not be required at that position. The number of discrete measurement locations shall then be reduced accordingly.
LpqT values shall be acquired, with a measurement time interval. T, of 3 s. The arithmetic mean of the values of thus acquired at the discrete measurement positions shall be calculated. This process shall be repeated three times, and the arithmetic mean of the three resulting values shall be calculated and rounded to the nearest integer for comparison with the requirements of the TSI.
If this value does not exceed the greater of the background noise levels measured before and after the measurements by 10 dB or more, the measurements of the external warning horn level are not valid.
7 Tests with the vehicle at maximum speed
7.1 Test conditions
7.1.1 Environmental conditions
The measurements shall be made in open country (ie not in tunnel, deep cutting or in the presence of noise
control barriers).
7.1.2 Vehicle conditions
7.1.2.1 General
Air management systems, including grilles, filters and fans, shall be clear of any obstruction. Windscreen wipers should not be in operation during the measurements. During the measurements, the doors and windows of the vehicle shall be kept closed. The minimum number of people necessary to carry out the acoustic tests shall be present in the cab during the measurements. The cab is to be in the condition that will apply when in service.
7.1.2.2 Normal operating conditions
The measurements shall be carried out in normal operating conditions defined as follows:
All equipment that operates continuously when the vehicle is running shall be operating at normal load, which is the performance at an external temperature of 20 °C. For Heating, Ventilation and Air Conditioning (HVAC) systems conditioning passenger areas and working places as well as system supplying energy for this function, climate influence parameters shall be set at: wind speed at 3 m/s, relative humidity at 50 %. 700 W/m2 energy from sun radiation, one person per seat.BS EN 15892-2011 pdf download.