state of cleanliness of a component or a fluid that fulfills the required cleanliness level


industrial process for the reduction of the quantity of contaminations present in a fluid or in respectively on a component

cleaning curve:

progress curve of the cleanliness level of a fluid or component subject to cleaning


condition of a product, surface, device, gas, fluid, etc. characterised by the absence of particulate contamination

component cleanliness code (CCC):

(alpha-numeric) expression of the cleanliness level (CL) of a component measured or specified by the particle size distribution of the contaminants

cleanliness inspection:

a range of operations aiming at bringing as much contaminants as possible from a component to a measuring apparatus for their analysis or quantification

Sequence of steps: 1. Aquistion of the component | 2. Extraction | 3. Analysis of the contaminants

cleanliness inspection equipment:

equipment necessary to determine the cleanliness level

cleanliness level (CL):

amount and/or nature of contaminant present on the controlled surfaces and/or in controlled volumes of a component

cleanliness specification:

document that specifies the cleanliness level required (CLs) for a given component along with the agreed inspection method

clean room:

room whose ambient particulate contamination level has no negative effect on the cleanliness measurements

room in which the concentration of airborne particles is controlled and which is constructive and used in a manner to minimize the introduction, generation and retention of particles inside the room, and in which other relevant parameters e.g. temperature, humidity and pressure, are controlled as necessary


presence of more than one particle in the sensing volume of an APC at the same time


general term used to cover a part, a component, a sub-assembly, a part assembly or a system fitted to a road vehicle

conditioning liquid:

liquid compatible with the extraction sample used for conditioning of the analysis equipment and/or monitoring of the blank value of the analysis set-up


undesirable substance which is in suspension in a fluid or in or on a component

controlled surface:

surface of a component subjected to a cleanliness requirement and/or subject of a cleanliness inspection

controlled volume:

volume of a component subjected to a cleanliness requirement and/or subject of a cleanliness inspection or measurement