The Star-News


Ins and outs of Oohs and Ahhs

Sun, Jul 03 2011 12:00 PM Posted By: Nohely Mendoza

When we think of Fourth of July, the first thing that comes to mind are fireworks.

Although the city of Chula Vista will not host a fireworks display this year, other cities in San
Diego County will.

Creating an explosive pyrotechnic display takes a lot of work and more than a year in advance to
plan out, say pyrotechnic experts.

“Fireworks come in different sizes, the bigger the size the more spectacular the show becomes,”
said Jerry Roberts of Pyro Magic Inc., who boasts a 65-year work history.

Fireworks use more than 20 different chemicals — everything from aluminum, which is used to produce silver and white flames and sparks; to potassium, which is used to oxidize firework mixtures; to titanium, which can be burned as powder and produce silver sparks to eventually produce color, powder, density and explosiveness.

“The size of the shell determines how high it goes in the air,” Roberts said. “For each inch of
the shell, it rises 100 feet.”

Due to the power and rise of a firework, observers must stay a good distance from the displays.

“There is a certain minimum distance required by the fire department,” Roberts said. “For low level devices it’s 75 feet minimum. For ariel shells it’s around 300 feet, and for six-inch shells it’s a distance of 1,800 feet.”

Because of the cardboard fragments that fall from the sky, the streets are usually closed for public
firework displays to prevent damage to property and people.

This year, firework displays for Fourth of July will be available for observance in more than 10 locations in San Diego.

• • •

Where in San Diego to get your firework fix this Fourth of July
(all shows begin at 9 p.m.)

 Downtown San Diego
La Jolla Cove
La Jolla Shores
Old Town Celebration
Coronado
Ocean Beach
Poway
Mira Mesa


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