Any asbestos exposure is too much! Any employer who knowingly allows workers to be exposed is neglegient and probably criminally liable. If there is good reason to suspect asbestos, and the employer will not address it, time to call OSHA. Please be aware that the dust present may not contain asbestos depending on what asbestos containing material is present. Better to error on the side of caution and get him out of there now.
KB
