High concentration of hydrogen in closed arear can be harmful for people as it lowers the amount of oxygen in the air. However, the concentration of hydrogen needed to create an environment with insufficient oxygen is much higher than the point of flammability; hence the danger of explosion is greater. Liquid hydrogen and cool gas released from the liquid can cause burns when in contact with the skin. Skin can stick to insufficiently isolated hydrogen containers and be torn from flash afterwards. Inhalation of pure hydrogen causes loss of consciousness and nearly immediate death.