Lifeproof case keeps water out but lets dust in?

[Colev1]

I have a lifeproof fre on my iphone 5 I've water tested it and it's all good, not a drop. However I'm in a work environment every day that is very dusty and dirty and though this case keeps water out there is dust under my screen constantly! Of course the charge port is open at night but that shouldn't let this much dust in and there is always a build up of dirt and dust on the yellow seel inside the charging port. Isn't this supposed to be an air tight case?

 

[maliu]

Was the phone used without a case? If so it can shed dust for awhile and make it seem like the case is not dust proof. The other way dust gets in is when you open the charge port and static sucks outside dust into the case.

 

[AndyinAtl]

Corley i always thought i alone had this problem. I know in my case its not static drawing dust in. When im in a work environment that involves sheetrock dust then that is what infiltrates. Georgia red clay dust? All up in it. Whats bizarre is that the case has never failed the water test.