Reaction-kinetic key figure. It specifies how much quicker a chemical reaction or the killing off of micro-organisms takes place with a temperature increase of 10 °C.

​Qualified Hygienic Design (test system for cleanability of components)
Stage 1 includes the theoretical proof of hygienic construction. The compliance with these standards relevant for the respective component can be documented by an own certificate and a QHD mark stuck to the component. The manufacturer hereby declares that he has complied with the state-of-the-art with regard to the requirements for a hygienic construction specified in the regulations.
Stage 2 is verified by a standard test developed by the Faculty for Machine and Apparatus Study of the University of Munich, Freising – Weihenstephan. (practical proof of cleanability)

​Execution and documentation of tests and trial runs. This serves to prove that a certain equipment brings the promised performance under real operating conditions.
See also Validation

​Is rapid cooling with the help of a cold gas or liquid. the cold coolant is directly mixed with the hot substance so that it can be cooled down more quickly.

​Value which is not specified by law
Recommended values may serve for quality assessment.

​Is a process in which the given value of a variable is established and maintained continuously by automatic intervention based on measurements.

​This pressure is formed from a prevailing pressure minus atmospheric pressure. In comparison with absolute pressure, which is related to a vacuum, relative pressure is related to ambient pressure.

​A relief valve is a valve set to a certain pressure. The valve opens when this pressure is exceeded.

​Resistance can be
a) Resistance of micro-organisms to certain substances (antibiotics, disinfectants, preserving agents) or methods (e.g. ionising radiations, heat etc.) or
b) Resistance of certain materials (e.g. stainless steels) to certain chemicals (e.g. HCL, H2SO4 and others)

​See also osmosisIn the case of reverse osmosis the effect of osmosis is reversed with the help of pressure. The side of the diaphragm with the higher share of liquid is pressurized. This diffuses the liquid through the diaphragm again, which increases the concentration on this side again.

​This code is used in flowmeters and describes the turbulence of flows. If the Reynolds figure reaches a critical value, a laminar flow becomes a turbulent flow.

​Elimination of product and cleaning agent residue with water.
Elimination of a medium (product, cleaning or disinfection agent) and removal of easily adhesive coatings on surfaces, e.g. with drinking water or sterilised water.

​Reverse Osmosis
Pressure-operated membrane separation method; approx. separation range of materials with mol wt. = 1000

​Water treated by reverse osmosis.

​Restriction of certain Hazardous Substances. This EU law stipulated that dangerous substances such as lead, cadmium, chrome 6, mercury are prohibited in electronic devieces. They must have a maximum weight percentage share of 0.01.

​Value no longer used today. Difference between maximum profile peak and profile valley.See Roughness parameters

​Comparable measured values determined from the roughness profile of technical surfaces by stylus instruments
The following are distinguished according to DIN 4768 Section 2.3:
Mean roughness value Ra = arithmetic mean of the distances between the roughness profile and the middle line within the measuring distance.
Single roughness depth Zi = distance between two parallel lines which touch the roughness profile at the highest and lowest point in a single measuring distance and the middle line.
Averaged roughness depth Rz = arithmetic mean of the single roughness depths of five consecutive measuring distances.
Maximum roughness depth Rmax = greatest single roughness depth occurring on the total measuring line.

​Cleaning with subsequent disinfection
Common English term for cleaning and disinfection (in the widest sense).

The sealing of an opening to prevent the penetration or through flow of unwanted substances in the long term.​

​A frequently misused term for the design and construction of a media-carrying component or plant section which enables the complete draining of a pipe system without outside intervention.
 The term suggests fully automatic draining. Complete self-draining is not possible in reality, especially because the increased adhesion of a working medium leads to the medium sticking partly to the surfaces of the pipe sections, valves or vessels to be emptied. Actually the optimisation of a plant can merely ensure that a so-called unhindered outlet can take place. Ideally no media residue in the form of puddles or clogged material remains in the pipe. To counteract an increased media adhesion it may be useful to fit transverse pipes and components with an appropriate drop/gradient. This is also recommendable to overcome gravity and define an orderly outlet in direction and time. See also Free outlet and Optimum draining.

​See instrument sensor

Mechacnical splitting of two-phase substances, e.g. emulsions​
 

​The actuation, e.g. a valve actuator, does not control the sealing mechanism of a valve directly but with the aid of the operating pressure applied in the valve. The necessary forces are generated by defined areas and their exposure to the operating pressure. Small control bores and channels serve for this so that relatively high operating pressures can be handled by relatively small actuators (usually electromagnetic). Terms such as forced lift and auxiliary controlled are also used manufacturer-dependently. Servo controls are also familiar for example as steering and brake assistance in vehicles.

The set value is the given/target variable w in a control (e.g. positioning distance/valve position in position controls or temperature, pressure, pH value, turbidity, volumetric flow in process controls).
 
See Command variable 'w'.

​Term used in linear operating valves, cylinders and combustion engines. The opening stroke/piston stroke is shorter than the nominal diameter of the valve seat/piston.

​Are electrical variables or pulses (e.g. voltage in Volt / V, current in milliampère / mA or frequencies in pulses per litre) which serve for transmission between different devices (e.g. sensors, instrument sensors, process controllers, position controllers, displays, recorders etc.).

Safety Integrity Level describes the safety of control systems. These are stipulated in standard IEC 61508. For receiving a SIL level there must be no serious failure within 10 years.

​See Roughness parameter

​See Disposables

​Sterilisation in place
SIP is the inside sterilisation of plants without disassembling these or making any significant changes to them in relation to their operating state. Is also sometimes known as Steam in Place as steam is often used as the sterilising medium.

​State of a surface which may correspond to operational and hygienic requirements.

​Every undesirable material including food remains, micro-organisms, cleaning agent and disinfectant residue.

​These valves are controlled vian an electromagnetic actuator. Solenoid valves have a fast operating time.

​Germ cells of micro-organisms which are also permanent forms in bacteria.
Permanent form of micro-organisms formed under unfavourable conditions which germinate in a favourable environment, reproduce and survive heating to 75 °C for 20 minutes. Bacteria spores have storage substances and solid, resistant cell walls.

​Spore exterminating. Sporicides are materials which exterminate spores.

​Term used in linear operating valves, cylinders and combustion engines. The opening stroke/piston stroke is equal to the nominal diameter of the valve seat/piston.

​Steam sterilisation is sterilisation with saturated water vapour of at least 120 °C.

​Free from reproductive micro-organisms and active viruses.

​Contamination-free sample taken for sterility test.
See also Sterile test.

​Test for proving the sterility.

Absolute sterility cannot be guaranteed in practice. Therefore sterility is only achieved with high probability by careful application of sterilisation methods and is already assumed at a maximum permissible colony number. This colony number must be proven by tests (validation).
 

​Application of method for achieving sterile conditions.
Sterilising is the extermination of micro-organisms and deactivation of viruses by physical, mechanical, thermal and chemical processes.

Absolute sterility cannot be guaranteed in practice. Sterility can only, therefore, be achieved with high probability by adopting careful sterilization processes with a maximum permissible number of colonies. This number of colonies must be verified by means of tests.

​A usually uncontrollable area at the bottom of a process plant component in which a substance may settle.
See Deadleg.

​There are three different types of surfaces:
Surface, geometric: An ideal surface the nominal shape of which is defined by the drawing and / or other technical documents. According to DIN 4760, sub-section 2.3.
Surface, actual: The approximate projection of the real surface of an element determined by measurement. According to DIN 4760, sub-section 2.2.
Surface, real: The surface which separates the object from the space surrounding it. According to DIN 4760, sub-section 2.1.
 

​Old term for surface colony numberShould not be used if possible.

​See Roughness parameters

​Changing a surface Changes are made for example by mechanical or electrochemical deburring in the micro and macro range.

​Is a mixture of substances consisting of a liquid and the solids distributed within it. These solids are scattered throughout the liquid in small particles.