| Tankers carrying cryogenic cargoes, such as LNG, are fitted with gas detector systems alarmed at 30% of the lower explosive limit. What is indicated if the gas detector alarms sounds? |
| A) an explosion is about to take place |
| B) the detector is sampling a space in which 30 percent of the atmosphere is explosive |
| C) a flammable vapor concentration exists at the sample point, but it is too lean to burn |
| D) the detector sensor is sampling a space where the cargo vapor concentration is 30 percent by volume |