Starting on May 7, billions of people around the world will be watching a single chimney. During the conclave at the Vatican’s Sistine Chapel, black smoke indicates no candidate has received the required two-thirds majority, while white smoke signifies the election of a new pope.
The color of smoke is also crucial in firefighting, providing insights into the fire’s nature and behavior to save lives.
“When reading smoke, the color matters,” says Glenn Corbett, a fire protection engineer.
[ Related: Pope Francis’ Climate Change Epiphany. ]
What makes smoke black?
Black smoke indicates the burning of heavy fuels or synthetic materials, signifying toxic fumes.
“When you see a lot of black smoke, you can guarantee that there’s a lot of carbon involved,” explains Corbett.
During the 2013 conclave, a mixture of potassium perchlorate, anthracene, and sulfur was used to produce black smoke.
This smoke signaling tradition dates back to 1903, with changes in the materials used over time.
What makes smoke white?
White smoke indicates the election of a new pope, generated by fires producing gas or water vapor.
“The key ingredients are oxidizers, which accelerate the combustion process,” explains Corbett.
In previous conclaves, distinguishing smoke colors was challenging. The 2013 conclave used potassium chlorate, lactose, and chloroform resin to create visible white smoke.
What can smoke tell firefighters?
Smoke, a deadly byproduct of incomplete combustion, contains aerosols, gases, and particulates, posing a significant risk during fires.
Firefighters analyze smoke color, velocity, and behavior to make informed decisions and ensure the safety of their crew.
Monitoring smoke anger can help predict flashovers and prevent dangerous situations.
“We use colors to establish if we’re controlling a fire,” adds Corbett, emphasizing the importance of reading smoke signals.
What times should viewers look for smoke during the conclave?
Viewers can expect smoke signals just after 7 p.m. local time on May 7 at the Vatican, with additional chances throughout the following days.
Predicting the timing of smoke signals is not precise due to variations in the conclave proceedings.
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