Chemical categorization respiratory

Respiratory protection is of primary importance since inhalation is one of the major routes of exposure to chemical toxicants. Respiratory protective devices (respirators) consist of a facepiece connected to either an air source or an air-purifying device (cartridge or filter). Respiratory protective equipment can be categorized into three types ... 

Toxicologists who study the responses of the respiratory system to foreign chemicals generally categorize those responses according to their biological and pathological characteristics. 

The factors and processes affecting the deposition of airborne substances in all regions of the respiratory tract can be broadly categorized as those related to the (1) structure of the respiratory system, (2) chemical and physical properties of the airborne substance, and (3) ventilatory functions including route of breathing (nasal, oral, and oronasal). 

Chemicals and chemical mixtures that attack the respiratory system are categorized as corrosives, irritants, and sensitizers. Though the term irritant is often applied in the literature to chemicals that are either corrosives or irritants, the definitions used here are those that follow. These definitions are identical to those used by toxicologists and regulatory agencies to classify the hazards due to chemical inhalation. 

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