16 CFR 1500.47 - Method for determining the sound pressure level produced by toy caps.

§ 1500.47 Method for determining the sound pressure level produced by toy caps.
(a) Equipment required. The equipment for the test includes a microphone, a preamplifier (if required), and an oscilloscope.
(1) The microphone-preamplifier system shall have a free-field response uniform to within ±2 decibels from 50 hertz to 70 kilohertz or beyond and a dynamic range covering the interval 70 to 160 decibels relative to 20 micronewtons per square meters. Depending on the model, the microphone shall be used at normal or at grazing incidence, whichever gives the most uniform free-field response. The microphone shall be calibrated both before and after the test of a model of cap. The calibration shall be accurate to within ±1 decibel. If the calibration is of the pressure type or of the piston-phone plus electrostatic actuator type, it shall be corrected to free-field conditions in accordance with the manufacturer's instructions.
(2) The oscilloscope shall be the storage type or one equipped with a camera. It shall have a response uniform to within ±1 decibel from 50 hertz to 250 kilohertz or higher. It shall be calibrated to within ±1 decibel against an external voltage source periodically during the tests.
(b) Procedure.
(1) Use the type pistol that would ordinarily be used with the caps being tested. Place the pistol and testing equipment so that neither the pistol nor the microphone is closer than 1 meter from any wall, floor, ceiling, or other large obstruction. Locate the pistol and the microphone in the same horizontal plane with a distance of 25 centimeters between the diaphragm of the microphone and the position of the explosive. Measure the peak sound pressure level at each of the six designated orientations of the pistol with respect to the measuring microphone. The 0° orientation corresponds to the muzzle of the pistol pointing at the microphone. The 90°, 180°, and 270° orientations are measured in a clockwise direction when looking down on the pistol with its barrel horizontal, as illustrated by the following figure:
(2) The hammer and trigger orientations are obtained by rotating the pistol about the axis of the barrel, when the pistol is in the 90° or 270° orientation, so that the hammer and the trigger are each respectively closest to and in the same horizontal plane with the microphone.
(3) Fire 10 shots at each of the six orientations, obtaining readings on the oscilloscope of the maximum peak voltage for each shot. Average the results of the 10 firings for each of the six orientations.
(4) Using the orientation that yields the highest average value, convert the value to sound pressure levels in decibels relative to 20 micronewtons per square meter using the response to the calibrated measuring microphone.
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Title 16 published on 2015-01-01

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 16 CFR Part 1500 after this date.

  • 2015-11-19; vol. 80 # 223 - Thursday, November 19, 2015
    1. 80 FR 72342 - Amendment To Clarify When Component Part Testing Can Be Used and Which Textile Products Have Been Determined Not To Exceed the Allowable Lead Content Limits; Delay of Effective Date and Extension of Comment Period
      GPO FDSys XML | Text
      Direct final rule; delay of effective date and extension of comment period.
      The effective date for the direct final rule published October 14, 2015, at 80 FR 61729, is delayed from December 14, 2015, until January 13, 2016. The rule will be effective unless we receive a significant adverse comment. If we receive a significant adverse comment, we will publish notification in the Federal Register withdrawing this direct final rule before its effective date. The comment date is extended to December 14, 2015.
      16 CFR Parts 1109 and 1500