There’s something about the night sky exploding with light, colors and sound that ignites universal pleasure during Fourth of July celebrations. With pleasure comes wonder. How are fireworks made? How do they get launched into the sky? How do they explode at the right time? Finally, what gives fireworks their color?
Heather Gobet is a licensed pyrotechnician and the marketing director for Western Display Fireworks LLC, a family-owned Oregon company that has been lighting up Blaine’s Independence Day for over a decade. Gobet cleared up some of the mystery behind how a display is set up and how the fireworks are launched.
Contrary to what people may imagine, most fireworks used in big displays are not rockets. A rocket carries a propellant, which is burned inside a cylinder, and its exhaust is expelled through a nozzle to push it upward. Gobet explained that their fireworks typically are more like mortars. A firework is placed inside an open-ended tube, and an explosion underneath it launches it out of the tube and up into the air.
The projectiles, called aerial shells, are typically sphere-shaped with a cone on the bottom. The cone contains black powder, which explodes first to launch the sphere upwards. The explosion also lights a four- or five-second fuse leading into the heart of the sphere, which then ignites a bursting charge. How that explosion manifests into patterns and sounds depends on how the components inside the sphere are arranged, Gobet said.
“Inside the aerial shell are spheres or cylinders made of paper mache or cardboard filled with compounds. The shape of the cartridges and how they are arranged within the aerial shell determines the pattern and the sound of the element,” she said.
Whistles, sizzles and loud booms (called salutes) are all part of the magic of the display.
“You try to get a wide variety of effects, and you choreograph each display to keep it interesting and match it to a soundtrack,” Gobet said. “Choreography is one of the most technical aspects of setting up a display.”
Every element of the display is carefully scripted well beforehand so the fireworks can be packaged accordingly. Western Display uses computer software and electronic fuses to precisely time its biggest displays, but most shows are still fired manually by pyrotechnicians, who wear motorcycle helmets and the same fire-resistant clothing worn by firefighters.
The logistics behind the displays is complicated, Gobet said. Transporting hundreds, or thousands of explosive fireworks to a site, then setting them up and firing them safely requires a lot of planning. It also requires coordination with the local fire marshal.
“There are a ton of legal and liability issues involved,” Gobet said. “Planning is paramount to safety.”
How do fireworks get their colors? In a word: Chemistry. John Conkling, a professor of chemistry at Washington College in Maryland specializes in pyrotechnic displays. He is the author of Chemistry of Pyrotechnics: Basic principles and theory.
In a YouTube video from the American Chemical Society, Conkling explains that to produce color, you start with a burning mixture of oxidizer and fuel then add color ingredients to it. Strontium chloride produces a red flame when burned. Orange and yellow can be made with sodium silicate, calcium nitrate or calcium carbonate, and green is often made with barium acetate. What about blue?
“Blue is the hardest color to produce pyrotechnically,” Conkling says. “You need perfect chemistry.”
Copper oxide is the primary compound to create a blue flame.
Pam Christianson organizes Blaine’s Fourth of July fireworks displays, and has been working with Western Display since before Blaine even had a Fourth of July celebration.
“They provided fireworks for the Skywater festival we used to hold in June,” Christianson said. “Because we’ve been a recurring customer for so long, they’ll often throw in some extra stuff that isn’t on the script, which is really nice. I think that’s part of having a good working relationship.”
The Blaine fireworks are often touted as superior to Bellingham’s display, Christianson said.
“People have told us that ours are bigger,” she said.
The fireworks display is scheduled to begin at 10:15 p.m. on the dot said Carroll Solomon, Blaine chamber secretary.
“Over the years we’ve found that’s the perfect time, when it’s just dark enough to begin,” she said.
Blaine’s action packed Old Fashioned Fourth of July kicks off the day before with an outdoor concert on Wednesday, July 3 at the G Street Plaza. The 133rd Army National Guard band, “Full Metal Racket,” will take the stage at 7 p.m.
The celebration continues July 4 with a pancake breakfast at the Senior Activity Center at 8 a.m., a parade at noon and a show and shine car show with more than 200 classic vehicles in attendance from 8 a.m. to 3 p.m.
Solomon said the parade attracted more than 10,000 people last year.
“You never saw so many people packed into downtown Blaine,” she said, adding that people should be prepared to park at the school and take the short walk into downtown.
There is still time to be in the parade, and no need to pre-register for the event. Parade staging will be on a first-come, first-served basis and will begin at 9 a.m. Judging will begin at 11 a.m.
A street fair will keep folks busy throughout the day, and downtown restaurants will have their doors open and seats out so customers can enjoy the festivities.
The fireworks will be launched from Marine Park.
Blaine residents will have premium views for the show. “Anywhere in downtown that faces the water, you can see the fireworks perfectly,” Solomon said. “Even Semiahmoo spit has a great view.”
For a full schedule of Blaine’s Old Fashioned Fourth of July events, visit blainechamber.com.