Is this an asbestos floor?
The only way to be sure is to send a sample to a testing lab. Send a sample of the adhesive too, since asbestos was sometimes mixed into that. I'm assuming this is tiles; if so you can lift one buy using a heat gun to soften the adhesive and gently lifting with a putty knife.

In most cases, encapsulating the suspect tile under a floating floor is acceptable if the stuff isn't already shedding fibers.