HomeNursing questions Normal plasma Prothrombin time (PT).. 11 - 16 Sec Normal plasma Prothrombin time (PT): a. 36 - 50 Sec. b. 11 - 16 Sec.*** c. 12 - 15 Sec. d. 1 - 4 min. Facebook Twitter Share:Normal plasma Prothrombin time (PT).. 11 - 16 Sec Facebook Twitter WhatsApp Pinterest LinkedIn Reddit Tumblr Telegram Email