This presentation discusses alternative testing methods for aerial shells in consumer fireworks and adult snappers.

1. Alternative Testing Methods for
Aerial Shells in Consumer Fireworks
and
Adult Snappers
Dr. Christopher J. Musto
Chemistry Division—Laboratory Sciences
The views in this presentation are those of the U. S. Consumer Product Safety Commission (CPSC)
staff and they have not been reviewed or approved by, and may not necessarily reflect the views of,
the Commission. 1

2. • U.S. CPSC Fireworks Standards Development
• Review of AFSL’s Black Powder Equivalency Test
• Measuring Dynamic Pressure
• Equipment
• Software
• Expertise
• Results
• Adult Snappers
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3. Bethesda, MD Rockville, MD
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4. • In 2006, the CPSC put forth an advance notice
of proposed rulemaking (ANPR) to amend the
regulations for certain fireworks devices.
• Since 2011, CPSC staff has been considering
possible alternatives to improve or clarify current
regulations.
• In 2012, a new approach to assess blast overpressure
of “whole-shell” aerial devices was evaluated.
• http://www.cpsc.gov/PageFiles/138398/Fireworks-Status-2013.pdf
• Staff continues to explore easy yet effective testing
alternatives.
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5. • Bans fireworks intended to produce audible effects …
if the audible effect is produced by a charge of more
than 2 grains of pyrotechnic composition.
• When the rule was written, consumer fireworks were
typically made with a black powder expelling charge
and flash powder in paper reports inside the shell.
• In implementing the rule, it has been assumed that
the sound of a report was a surrogate for its explosive
power.
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6. Consumer Consumer Professional
Firecracker Aerial Device Aerial Device
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8. 8

9. Staff initiatives:
• determine the potential risks associated with
aerial devices due to blast overpressure
• coordinate with experts in the field
• develop a test to objectively determine overload
limits
• ensure test methods are effective and safe
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12. 12

13. • Total pressure versus static pressure – different
measuring techniques
• Magnitudes slightly different, but similar behavior
• Short rise time leads to strong pressure front
• Pressure wave velocity affects damage
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14. • Dynamic Pressure Sensor Range: 0 – 500 psi
• Pressure Sensor Distance to Shell: 5.5 inches to center
• Data Acquisition Rate: 50,000 acquisitions per second
• Pressure Sensor Sensitivity: 10 millivolts per psi (1 volt = 100 psi)
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15. Effects Containment Dynamic Pressure
Cage Transducer
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16. 3 grams of flash powder (5.5 inches from sensors)
Peak: 167 psi
Average: 142 psi
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23. • Large shells produce explosions with pressure waves that
are similar to an M-80 at close range.
• Large shells are designed to function 100+ feet in the air,
reducing risk of injury.
• The AFSL test can distinguish the power of black powder
versus hybrid powder versus flash powder, but it does not
consider how much powder is present in the shell.
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24. Fused Firecracker (1 inch) Adult Snapper (0.7 inch)
1.00
7.50
Pressure: ~ 6.5 psi 0.75
Pressure: ~ 0.88 psi
5.00
0.50
2.50
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0.25
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r
,
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-2.50
-0.25
-5.00
-0.50
-7.50
Adult snappers typically have 1/8 the energy of consumer firecrackers.
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25. • Experiments show the pressure associated with adult
snappers is about 14% of the pressure from legal
firecrackers.
• 16 CFR §1500.17(a)(8) limits firecracker-type devices
intended to produce an audible report to 50 mg of
pyrotechnic material.
• Devices, including adult snappers, are subject to FHSA
labeling: “Use only under [close] adult supervision”.
• There is no evidence of mass detonation associated with
boxes of 20 or cartons of 600 devices, when they are
dropped from a height of up to 8 feet.
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26.  www.cpsc.gov
 www.SaferProducts.gov (REGISTER)
 www.recalls.gov
 Recall Handbook (pdf) (Revised March 2012)
 Christopher Musto– 301-987-2090
 CMusto@cpsc.gov