How not to do the rainbow flame demo, Woodson High School edition

Both DC area station WJLA and the Washington Post have the reports from the Woodson High School fire from last year. The details from Post reporter Moriah Balingit aren't pretty (emphasis mine): 

...The school system, which said little about the accident in the fall, confirmed this week that the teacher violated safety protocols because neither she nor her students were wearing safety goggles during the demonstration, which involved her pouring the flammable liquid onto a table. The demonstration created what one student described as a “splash of fire” that burned students nearby. 

While a ventilation hood would not have been required, an expert said it should have been used and could have prevented or mitigated the fireball that burned five students and the teacher. Two students had to be flown to hospitals with serious burns.... 

The Virginia Occupational Safety and Health found no workplace safety violations at Woodson as a result of an investigation that concluded in December. WJLA first reported on that agency’s findings last week. 

According to the investigative report obtained by The Washington Post via the Freedom of Information Act, the teacher told investigators that she poured ethyl alcohol from a beaker out onto a demonstration table and ignited it. She then introduced different kinds of salts to the flame. 

When the flames began to die down, according to the report, she lifted a large jug of the flammable liquid by its mid-section and dumped it onto the table. The bottle compressed, creating what officials called a “bellows effect” that shot a plume of flammable vapor out of the bottle. A burst of air from an HVAC vent might also have propelled the vapors. 

The vapor ignited, generating a large fireball that burned nearby students. The blaze melted plastic chairs and charred a backpack, according to investigative photos. 

The report notes that the classroom had a bevy of safety equipment, including lab gloves, aprons, safety goggles and a ventilation hood. Though the safety equipment was not in use, investigators concluded that no citations were warranted because of a lack of classroom guidelines. 

“The school curriculum for this demonstration does not provide any detailed instructions on how a teacher should perform the demonstration,” investigators wrote.

Once again, we have the bulk container of the flammable solvent playing the key role in the injury of chemistry students during the rainbow flame demonstration.

Now is a good time to note a previous set of rainbow flame demo injuries has resulted in a $1.5 million dollar settlement from a Georgia school district.