The illustration shows a generic example of a box plot with the maximum, third quartile, median, first quartile, and minimum values labeled. The relative vertical spacing between the labels reflects the values of the variable in proportion.
Respirator Types Two basic types of respirators are: â¢ air-purifying; andâ¢ supplied-air respirators. Air-purifying respirators remove airborne contaminants such as particles, toxic vapors, and/or gases.
When should a respirator be used? Workers should use respirators for protection from contaminants in the air only if other hazard control methods are not practical or possible under the circumstances. Respirators should not be the first choice for respiratory protection in workplaces. They should only be used: when following the hierarchy of control is not possible (elimination, substitution, engineering or administrative controls)