While taping moving boxes i was stuck by tape dispenser's serrated blade (very slight bleeding, minimal). person using it before me did same to themselves 30 min. prior. any blood on blade wasn't obvious to the naked eye. does hcv transmit this way?

HCV has not been known to be acquired by contact with contaminated environments, including sharp instruments like this. No risk and nothing to worry about -- only from direct contact with much larger blood exposure than is possible in this situation. Don't worry about it.

HCV transmission is highly unlikely in above mentioned scenario. Superficial skin infections remain possible and the wound should be watched closely until healed.