Brett Gardner’s son died of carbon monoxide poisoning. Carbon monoxide is known as the “invisible killer” because it is a colorless, odorless, tasteless gas or liquid. Here’s how to protect yourself and your family from carbon monoxide poisoning while traveling.

Miller Gardner -- the 14-year-old son of former New York Yankees outfielder Brett Gardner -- died from carbon monoxide poisoning, Costa Rican authorities have said.

A toxicology report after his death found high levels of carboxyhemoglobin, an indicator of carbon monoxide in the blood, according to a statement from Randall Zúñiga, the director of the Costa Rica Judicial Investigation Agency. Miller Gardner’s test showed a saturation of 64 percent, he said, adding that anything over 50 percent was lethal.