NFPA 85-2019 Boiler and Combustion Systems Hazards Code.
3.2.6 Shall. Indicates a mandatory requirement. 3.2.7 Should. Indicates a recommendation or that which is advised but not required. 3.2.8 Standard. An NFPA Standard, the main text of which contains only mandatory provisions using the word “shall” to indicate requirements and that is in a form generally suitable for mandatory reference by another standard or code or for adoption into law. Nonmandatory provisions are not to be considered a part of the requirements of a standard and shall be located in an appendix, annex, footnote, informational note, or other means as permitted in the NFPA Manuals of Style. When used in a generic sense, such as in the phrase “standards development process” or “standards development activities,” the term “standards” includes all NFPA Standards, including Codes, Standards, Recommended Practices, and Guides. 3.3 General Definitions. 3.3.1 Agglomerating. A characteristic of coal that causes coking on the fuel bed during volatilization.
3.3.3 Air Change. A quantity of air, provided through a fuel bumer, equal to the volume of furmace and boiler gas passes. 3.3.4 Air Register A set of dampers for a burmer, or air supply system to a particular burmer, used to distribute the combustion air admitted to the combustion chamber. Frequently controls the direction and velocity of the airstream for efficient mixing with the incoming fuel. 3.3.5 Air-Rich. Indicating a ratio of air to fuel supplied to a combustion chamber that provides more than the minimum excess air needed for optimum combustion of the fuel. 3.3.6 Alarm. An audible or visible signal indicating an off- standard or abnormal condition. 3.3.7 Alteration. A change or modification that results in a deviation from the original design specifications or criteria. 3.3.8 Annunciator. A device indicating an off-standard or abnormal condition by both visual and audible signals. 3.3.9 Atmospheric Fluidized Bed Combustion. A fuel-firing technique using a fluidized bed operating at near-atmospheric pressure on the fire side. 3.3.10 Atomizer. The device in a burner that breaks down liquid fuel into a finely divided state. Mechanical Atomizer. The device in a bumer that breaks down liquid fuel into a finely divided state without using an atomizing medium.NFPA 85 pdf download.