2010 SCCA Rulebook [Archive] - San Diego Region SCCA Forums

oinojo

03-08-2010, 12:50 PM

APPENDIX I - SOUND MEASUREMENT PROCEDURES

The provisions of this section are recommended, but not presently required.
The specific DB levels (values of “XX”) are expected to be assigned by Regions according to the needs of their sites.

The competitor shall carry sole responsibility for ensuring their vehicle
complies with these Sound Control Standards and Procedures.

Vehicle sound emission is not a constant factor that can be trimmed to barely legal (in the manner of engine displacement or vehicle weight.) Sound emissions may vary signifi cantly from morning to afternoon, and day to day, so the competitor is advised to target any vehicle sound emission level “adjustments” to well under the limit, to allow for variations in conditions.

The intent of the following rules is to truly make our events quieter by limiting the sound level produced by individual vehicles.

Competitors are expected to use mufflers as the primary method for sound reduction. Sound measuring stations will be on both sides of vehicles to ensure sound output levels are below limits.

STANDARD
Maximum limit of (XX) dB, A weighted, at the measuring point.

MEASUREMENT
The measuring point will be established during course set up, and approved by the event chair. The course map shall be provided to the chief of sound two days before the event.

When possible, measurements will be taken at all event sites to provide information for competitors.
Measurement will be taken at a point on course where the car can reasonably be expected to be at full throttle, under load, and at high RPM.

The measuring point will be 50 ft from the edge of the course lane, using a coned gate as a reference. More than one measuring point may
be established.

SOUND STATION(S)
A Sound Station will be established at the measuring point(s) on the course.- At a minimum, an ANSI Type 2 sound with a digital readout will be used.

The meter will be mounted on a tripod, 3-4 feet above ground level. The meter will be positioned perpendicular to the vehicle’s direction of travel. The meter will be set to “A” weighting, “Slow” Response.

When possible and practical, the Sound Station(s) will be as far away as practical from inhabited buildings. The Sound Station Operator will record the Heat #, Run #, Car # and Class and Sound Reading, on a Log developed for that purpose. Sound Logs will be posted on site after each run group, and on the web following the event.

Sound Logs will be maintained for one year. Every car will be measured on every run. The Sound Station Operator and the Grid Sound Control worker will be equipped with a radio on the same channel as the Corners, Grid and Control.

One or more (as required) of the “downstream” corner stations will be equipped with a black flag and dedicated flagger. The Sound Control Grid worker will be equipped with a clip board and notepad to record the car number of violators announced by the sound operator, for his reference when the car returns to Grid.

VIOLATIONS
When a vehicle exceeds (XX – 3) dBA, the sound operator will inform the grid sound control worker.
When a vehicle exceeds (XX + 3) dBA, the sound operator will announce over the radio, “sound fl ag, sound fl ag,” then state the car number and class, and the measured reading.

The Grid Sound Control Worker will record the car number and sound reading. The corner station(s) with the black fl ag will display it when called by Sound Control, so it can be seen by the driver, signifying to the driver that his vehicle has exceeded the (XX + 3) dBA secondary limit.

The driver must immediately come off the throttle and continue through the course, without either stopping or driving at a competition pace. Any run (XX) dBA or over will be scored a DNF. The driver will be notified of any measurement over (XX – 3) dBA. When a car in violation ((XX) dBA or over) returns to grid, the Grid Sound Control worker will notify the driver of the car’s measured sound level.

The driver will be given the opportunity for a “mechanical delay” to attempt to reduce the vehicle’s sound level. If, in the judgment of the Grid Sound Control worker, the driver has attempted a viable remedy, he will authorize a “second chance run”. If the driver(s) declines any “repair” action, or the “repair” is deemed inadequate or inappropriate by the Grid Sound Control Worker, the driver(s) will forfeit all subsequent runs in that vehicle. The Grid Sound Control Worker may offer advice to competitors.

This advice, however, shall be in no manner be construed to imply that said suggested corrective action(s) absolves the competitor from complying. If the vehicle exceeds either limit on the “second” chance run, the vehicle may be given one “fi nal chance” run if the vehicle meets all the requirements of the previous paragraph (second chance run). If the vehicle exceeds the limit on the “final” chance run, all subsequent runs by that vehicle, if any, are forfeited.

Drivers may appeal the decision of the Grid Sound Control Worker to the Event Chair