See also: Dealing with Breathing Problems written for patients. The term hyperventilation describes excessive ventilation of the lungs, beyond what is required to achieve normal arterial blood gases.
A light frost occurs when the temperature drops to below 32 degrees Fahrenheit, and refers to the conditions that allow a layer of ice crystals to form when water vapor condenses and freezes without first becoming dew. Harvest basil and other tender herbs before a light frost (when the temperature drops to 32 degrees Fahrenheit). 2  Even if they survive the frost, they don't do well in cold temperatures. 3  The same is true for most annuals.
Frost or freezing occurs when the temperature of air falls below the freezing point of water (0 Â°C, 32 Â°F, 273.15 K). This is usually measured at the height of 1.2 m above the ground surface. There is a rather subjective scale to show several degrees of frost severity: 1  slight frost: 0 to â3.5 Â°C (32.0 to 25.7 Â°F) 2  moderate frost: â3.6 to â6.5 Â°C (25.6 to 20.3 Â°F) 3  severe frost: â6.6 to â11.5 Â°C (20.2 to 11.3 Â°F) 4  very severe frost: below â11.5 Â°C (11.3 Â°F)