February 28, 1987 |
|Height||5 ft 11.5 in (182 cm)|
|Weight||176 lb (80 kg; 12 st 8 lb)|
|AL-Bank Ligaen team||Rødovre Mighty Bulls|
In 2003 Dahm moved to Malmö Redhawks and played on Malmö's junior teams.
In 2005 Dahm was drafted by the Belleville Bulls of the OHL. He played the 2005-06 season with the Bulls before being traded to the Sarnia Sting in the off-season. Dahm was named to OHL Rookie second team for the 2005–06 season. During the 2006–07 season, Dahm was traded again, this time to the Sudbury Wolves. Dahm enjoyed a strong playoff at the end of the 2006–07 season with the Wolves backstopping the team to the OHL finals where they would eventually succumb to the Plymouth Whalers. He decided to stay with the Wolves for the 2007–08 season as an overager. During the 2007–08 OHL season, Dahm was traded again moving to his fourth team in the OHL, the Niagara IceDogs. He is the first Danish goaltender to play in the Canadian Hockey League.
In December 2006, Dahm played a key role as he backstopped the Danish team, playing on home ice in Odense, as it gained promotion from the World Junior Ice Hockey Championships Pool I to the top flight for the first time ever. Dahm posted a .918 save percentage and a 2.20 GAA in 5 games.
Dahm was named the CHL Goaltender of the Week for the week ending January 13, 2008  and the week ending January 27, 2008. He was also named OHL player of the week for the week ending January 27, 2008.
Following the first week of the 2008 OHL playoffs, Dahm was once again named as the OHL player of the week for the week ending March 24. During the week he recorded 3 wins and 0 losses with 2 shutouts in the opening 3 games of their first round series versus Mississauga St. Michael's Majors. For the week he had a 0.33 goals against average and a .989 save percentage. He was the first star in two games and the third star in the third.
Following his junior career, Dahm signed with the Columbus Blue Jackets organisation and spent the 2008-09 season split between the Syracuse Crunch of the AHL and the Johnstown Chiefs of the ECHL. The following season, Dahm spent with the Alaska Aces of the ECHL, part of the season on loan with Bloomington PrairieThunder of the IHL.
Dahm did not secure a contract before the start of the 2010-11 season and waited until the start of December to sign a short-term contract with his childhood team Rødovre Mighty Bulls. Rødovre needed instant cover as one of their goalies was injured and another was away with the Denmark men's national junior ice hockey team for the 2011 World Junior Ice Hockey Championships Division I in Slovenia. While his stay with Rødovre was successful, the two sides could not agree on an extension of the contract and after only two games with Rødovre, Dahm was snapped up by EfB Ishockey, another Danish League team.
In a somewhat surprising move, Dahm returned to play for Rødovre Mighty Bulls for the 2011-12 season.
The Danish national team coach Per Bäckman has stated that provided Dahm gets sufficient playing time, he would be considered for the 2011 IIHF World Championship team Denmark roster. Eventually, Dahm was not selected for the final roster.