Before going blind Kai was used to help sniff out flammable liquids at fire scenes once blazes were extinguished to see if accelerants had been used and arson committed in a role that meant he relied on his nose just as much as his eyes.

Source: https://www.expressandstar.com/news/local-hubs/wolverhampton/penn/2023/01/14/fire-investigations-dog-goes-blind-overnight---but-theres-hope-he-could-regain-some-vision/