James Edgar had planned to turn up the heat and pop the question to Helena Bancroft after the event.
But when fellow firefighters discovered his plans they encouraged him to do it during the 200th West Yorkshire Fire and Rescue Service (WYFRS) trainee course graduation ceremony - in front of family and friends.
In the video, the firefighters can be seen taking part in a dazzling water display, before James emerges from the group with a bunch of flowers.
His girlfriend of five years, Helena, is called to the front, shielding herself from the pouring rain with an umbrella, before James kneels in front of her holding up a shiny engagement ring.
To his, and his colleagues, delight, Helena said a resounding "yes" and embraced him a big kiss.
His fellow firefighters then come forward and join in the group hug.
James was one of 22 firefighters who graduated from his training course, ready to keep the public safe across West Yorkshire, at the event at the HQ at Birkenshaw, Bradford, on Thursday.
James, from Huddersfield, said: “I’ve thought about proposing for a long time, and thought it would be a special way to do it after the ceremony.
"But when my fellow trainees found out about it they insisted I should do it as part of the graduation display - in front of everyone.
“We got it all planned out, everyone was really supportive even to the point where they planned they could turn the hoses on her if she did say no.
“But obviously I’m so happy she said yes – we’ve no plans for the wedding at the moment, we’re just going to enjoy being engaged for a bit.”
Alongside James and Helena’s happy news, awards were handed out for best watch, top trainee, and trainee’s trainee.
The new recruits also demonstrated putting out a building fire, rescuing a casualty from a mock-up road traffic collision and extinguishing a car fire.
Looking for on-call firefighters
WYFRS is not currently recruiting full time firefighters – however is looking for on-call firefighters.
On-call firefighters are skilled people from all walks of life who offer daytime, evening and/or weekend cover at on-call fire stations in addition to their normal, day-to-day commitments.
Just like their full-time counterparts, they work on the front line protecting their community.
On-call firefighters are not based at station, but when on-call, individuals must be able to reach their station within five minutes of their pager going off.
If you feel inspired by our newest recruits and live or work in Featherstone, Mirfield, Ilkley, Mytholmroyd, Otley, Silsden, or Slaithwaite then visit the website.