Scratches across b&w film negatives

Recently i got 3 rolls of color film developed and 3 rolls of black and white done. The black and white were shot between the 3 rolls of color film. All the black and white negatives had scratches across the negatives but none of the color ones did, (b&w shot from 2 separate cameras). Can anyone help me understand why this would happen or perhaps look at the negatives too help me prevent this in the future.

The fact that they appear on your B&W and not your color points to a processing error.

Did you process the B&W yourself or did you have it done at a lab?

Also, what format is this? If it's 645 or a cropped 6x6, the direction of the scratches makes sense for a processing error. If it's 6x7, it doesn't.

In any case, for lab processed film a dirty transport roller can cause this-basically it's a lack of "hygiene" in the processing machine. At home, I refuse to use squeegees because they can cause issues like this.