penetrant

A penetrant is the cause for a service penetration firestop. Building codes can refer to mechanical and electrical penetrants as "services".Penetrants are the mechanical, electrical or structural items that pass through an opening in a wall or floor, such as:pipeConduit (electrical)ductingcablescable traysstructural steel beams and columnsWhen these items are traversing a wall or floor assembly required to have a fire-resistance rating, they create the need for an opening, consisting of the space(s) between penetrant and surrounding structure, which must be firestopped in order to restore the fire-resistance rating of the parent assembly.
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adv. penetratingly, while permeating; persistently, assertively

adj. piercing, perspicacious; penetrating, searching; sharp, acute, keen

v. penetrate, enter; percolate, perforate, permeate; get across, get through

(a.)
Having power to enter or pierce; penetrating; sharp; subtile; as, penetrant cold.
  

(pătrunzător) = penetrating