Col. Tyler, in describing an older generation infrared sensor says that "the noise to signal ratio is too low". The correct term is "signal to noise ratio."
The bubonic form of plague is nowhere near 90% fatal, especially in the age of antibiotics. The pneumonic form is much more deadly, if untreated, and could easily meet or exceed that threshold.
At the end, when the suspect is between Williams and McGarrett, Danny fires a shot at the suspect. No policeman would ever fire at someone with an innocent person directly behind, especially when that person is his boss.
The foil suits worn by Five-O while they search Fong's house are US military fire suits, not HAZMAT suits. The fire suits do not afford the same degree of protection against biological agents.
The motorcycle is clearly a two-stroke Yamaha but the sound is from a twin four-stroke bike.
Every time McGarrett speaks the name of the ship, the dialogue doesn't follow his lip movements. The name of the ship may have had to be changed after the initial filming for some reason.
When Dr. Kemp injects Chin while Danny and Kono watch, Chin still has a thermometer in his mouth. Doctors and nurses know not to inject someone like this, since a person may instinctively clench his jaw and cause a serious injury.
When the doctor was getting ready to give the little boy a shot she pulled back on the plunger of the syringe but the needle wasn't in a bottle so she would just have been drawing in air.
The motorcycle rider makes a phone call wearing his helmet. He would not have able to hear due to the helmet covering his ears. He is later shown riding at night wearing the dark visor. He would not be able to see where he was going given the dim headlight of the older motorcycle.