The automatic cab signal system shall be arranged so that cab signals will be continuously controlled in accordance with conditions described in Â§ 236.205 that obtain at least stopping distance in advance. Â§ 236.512 Cab signal indication when locomotive enters block where restrictive conditions obtain.
Dissolved oxygen (DO) is a measure of the quantity of free oxygen molecules in water. The concentration of DO is an important indicator of the health of an aquatic ecosystem because oxygen is essential for almost all forms of life. Oxygen is necessary for respiration and for some chemical reactions.
An SaO 2 (arterial oxygen saturation) value below 90% causes hypoxemia (which can also be caused by anemia). Hypoxemia due to low SaO is indicated by cyanosis. Oxygen saturation can be measured in different tissues: 1  Venous oxygen saturation (SvO 2) is measured to see how much oxygen the body consumes.2  Under clinical treatment, a SvO 2 below 60% indicates that the body is in lack of oxygen, and ischemic diseases occur.n medicine, oxygen saturation (SO 2), commonly referred to as sats, measures the percentage of hemoglobin binding sites in the bloodstream occupied by oxygen. At low partial pressures of oxygen, most hemoglobin is deoxygenated.