When remediating mold, it is always recommended to remove the mold with an antimicrobial solution and a physical wipe down of the entire affected area. By just spraying the mold with an antimicrobial, a contact kill can be achieved, however a majority of the bulk material growth, though dead, will remain giving the appearance of active mold growth. This residual material will eventually dry and flake becoming airborne. This can enter your living space as 50% of the air you breathe in your home comes from the crawl space. This airborne mold, though dead, can still be harmful to your health as a respiratory irritant. Please keep in mind that everyone reacts differently to this.