User Manual

e1851a
32
Siemens Building Technologies
Cerberus Division
01.2002
8 Terms, Definitions
Airborne contamination
Contamination of the air due to particles.
Airlock
Room with mutually bolted doors between two or more rooms of different cleanliness clas-
ses or different pressure levels. It may be designed for the movement of personnel or ma-
terial.
Changing rooms
Rooms to change clothes before entering or leaving clean rooms and/or aseptic areas.
Clean room
A clean room in a manufacturing plant is an area which makes particularly strict demands
on the cleanliness of the room air, the workplace, the process media as well as the person-
nel.
Clean workplace
A controlled area with a cleanliness level corresponding to a defined air cleanliness class.
The personnel can stay either within the clean workplace (cleanroom) or outside
(e.g. clean work bench or clean cubicle)
Different types of clean work places can be distinguished by size and structural demarca-
tion, e.g.:
– clean room (personnel work in the room);
– clean cubicle (personnel only open the all-enclosed cubicle if required);
– clean room tent (clean area enclosed by foil);
– clean work bench (personnel take action but are situated outside);
– isolator (action only by means of gloves or half-suits).
Cleanliness
Air cleanliness at the work place is particulate cleanliness i.e. the absence of airborne con-
tamination (particles) which appear as dust, mist, or micro-organisms. This cleanliness is
defined by the particulate concentration per volume unit.
First air
Air entering the clean area through high-performance air filters or downstream distribution
equipment.
Isolator
Pharmaceutical minienvironments are called isolators, and they permit, for the aseptic ma-
nufacture of medical products to obtain sterility assurance levels
Leak
A point in a filter element at which the local efficiency of the filter is lower than a given limit
value.
Minienvironment
A compact localised enclosure with the purpose of isolating the process from its environ-
ment and from people.
Non-unidirectional airflow
An air handling method where first air entering the room mixes with the more contaminated
indoor air by means of induc tion. This type of air handling results in a dilution of the particu-
late concentration (dilution air handling).
Particle size
The apparent maximum linear dimension of a particle.
Particle/particulate contamination
Minute objects of solid or liquid composition with defined physical limits.
Fibers are particles with a length/diameter ratio greater than 5.