Long left West Brom to move to the KC Stadium in January and has made an instant impact, scoring twice in his first seven Premier League appearances for Hull.
The former Reading striker faces his former club for the first time this weekend when West Brom travel to Hull and Dawson, who is set to replace the suspended Jonas Olsson, knows the danger posed by the Republic of Ireland international.
The 27-year-old spent two-and-a-half seasons at West Brom, scoring 22 goals in all competitions, and Dawson hopes his familiarity with Long will help them nullify his threat.
"We've just got to be focused and alert all game because he's (Long) always alive," the defender told West Brom's official website.
"He's a great player and a great lad as well, it'll be a tough task for us to keep control of him but I'm sure we'll know all of his runs and his movements as well so it'll be a good test.
"We both know each other. We go into every game knowing about the strikers but especially Shane, we'll have to be alert all game."
Dawson made his fourth start of the Premier League campaign in the 2-1 win over Swansea City last Saturday and, with Olsson banned for two matches, is hoping to impress head coach Pepe Mel.
"It's a massive opportunity," he added.
"Obviously we need someone to step in and help the defence and hopefully I can do that."
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