Cleanliness suitability and cleanroom suitability tests at

Fraunhofer Institute for Manufacturing

Engineering and Automation IPA

Director

Prof. Dr.-Ing. Fritz Klocke

Prof. Dr.-Ing. Thomas Bauernhansl

Nobelstrasse 12

70569 Stuttgart

Phone +49 711 970-00

Fax +49 711 970-1399

Report No. ME 1811-1085

Stuttgart, Germany, January 28, 2019

Test report

Cleanliness suitability and cleanroom suitability tests at Fraunhofer IPA

Customer: Memmert GmbH + Co. KG

Äußere Rittersbacherstrasse 38

91126 Schwabach

Germany

Project Manager: Dr.-Ing. Frank Bürger

Project Assistants: Dipl.-Ing. Eileen Junghans

Cleanliness suitability and cleanroom suitability tests Fraunhofer IPA 2 Report No. ME 1811-1085

Index

1 Introduction and objectives 3

2 Overview of the measurements 4

3 Overview of results 6

4 Airborne particle emission tests 7

4.1 General information 7

4.2 Cleanroom environment 8

4.3 Test set-up and parameters 8

4.4 Measuring equipment 11

4.5 Localization tests 11

4.6 Qualification measurements 12

Procedure 12 4.6.1

Test piece TP01: description of the measuring points MP01 to 4.6.2MP09 13

Test piece TP02: description of the measuring points MP10 to 4.6.3MP19 16

Analysis of the results from the airborne particle emission tests 19 4.6.4

Course of particle emissions over time of TP01 19 4.6.5

Course of particle emissions over time of TP02 21 4.6.6

4.7 Classification 24

Statistical verification of the test results 24 4.7.1

Mean and maximum particle emission values and classification of 4.7.2TP01 25

Mean and maximum particle emission values and classification of 4.7.3TP02 28

4.8 Summary of the classification results 33

4.9 Annex: comparison of different classifications of airborne particulate contamination 35


1 Introduction and objectives

The Memmert GmbH + Co. KG is a manufacturer of warming cabinets, cooled incubators and tempering baths, which are used in research and development in laboratories. These are manufactured to high standards of quality and successfully implemented in a wide range of industries.

To secure its position in the market, the company wishes to extend the use of its products to the clean applications. For this, it is imperative to understand the contamination behavior of these products, as well as their suitability for use in cleanrooms and with regard to cleanliness.


2 Overview of the measurements

Tests were conducted on the constant climate chamber HPP1060 and the universal Oven UF1060 which are henceforth simply called test piece TP01 and TP02 in the report.

The following tables show the exact breakdown of the test pieces:

TP01

Description of test piece Constant climate chamber HPP1060

Description of test piece (short form)

HPP1060

Company name Memmert GmbH + Co. KG

Category Subcategory

Process Equipment Heating and Cooling

Serial number W918.0086

Color Stainless steel

Manufacturing date 9/2018

Test piece data TP01 Figure 1

TP02

Description of test piece Universal Oven UF1060

Description of test piece (short form)

UF1060

Company name Memmert GmbH + Co. KG

Category Subcategory

Process Equipment Heating and Cooling

Serial number B918.0087

Color Stainless steel

Manufacturing date 9/2018

Test piece data TP02 Figure 2


The following table shows the corresponding tests carried out on all test pieces:

P

art

icle

em

issi

on

ESD

beh

av

ior

Ou

tgass

ing

Ch

em

ical re

sist

an

ce

Cle

an

ab

ilit

y (

part

icle

s)

H2O

2

ab

sorp

tio

n/d

eso

rpti

on

Bio

log

ica

l re

sist

an

ce

Su

rfa

ce r

ou

gh

ne

ss

Exp

ert

ise

TP01 X

TP02 X

Table of test pieces and corresponding tests Figure 3


3 Overview of results

TP01: Particle emission (ISO 14644-1, -14)

Test parameter(s) Air Cleanliness Class

Outside: T = 50° C; humidity = 10 % 5

Inside: T = 50° C; humidity = 10 % 5

Overall result 5

TP02: Particle emission (ISO 14644-1, -14)

Test parameter(s) Air Cleanliness Class

Outside: T = 300° C; flap = open; fan = 100 % 6

Inside: T = 300° C; flap = open; fan = 100 % 6

Inside: T = 300° C; flap = open; fan = 0 % 6

Overall result 6

Overview of results Figure 4


4 Airborne particle emission tests

4.1 General information

A major criterion in clean and hygienic areas in industry and research is the concentration of airborne particles. Besides the quantity of particles per unit of volume of air, the size distribution of the particles is also critical when it comes to fulfilling cleanliness requirements.

Cleanliness requirements are set against the release of particles from the operating utilities used in clean or hygienic areas. The cause of particle emissions from operating utilities is generally tribological stress, which leads to wear and the generation and release of particles.

To determine the release of particles from operating utilities, particle emission measurements can be conducted in a test cleanroom with a low-turbulence displacement airflow following the procedure laid down in ISO 14644-14. The results enable the suitability of operating utilities to be determined for use in discrete air cleanliness classes according to ISO 14644-1. The VDI 2083 series uses the term cleanroom suitability to describe the suitability of operating utilities for discrete air cleanliness classes. Cleanroom suitability is one aspect of cleanliness suitability, which also includes all other cleanliness criteria relevant to a process. Apart from the release of particles, other cleanliness suitability criteria are, for example, chemical resistance, biological resistance, microbicidity and outgassing from materials, as well as the cleanability and hygienic design of components or equipment.

In the case of operating utilities such as manufacturing equipment, particle emission measurements serve not only to determine the influence of these systems on the environment (protection of the cleanroom) but also on the interior of the equipment itself (protection of the product).

By conducting localized particle emission measurements with optical particle counters in a test cleanroom with a low-turbulence displacement airflow, the cause of high particle emissions can be derived from the results obtained from the various measuring points.


4.2 Cleanroom environment

All tests are carried out in the Fraunhofer IPA competence center for ultraclean technology and micromanufacturing. Measurements are performed in a cleanroom fulfilling Class 1 specifications (in accordance with ISO 14644-1). A vertical low-turbulence displacement airflow prevails in the cleanroom. Air is introduced via the ceiling and extracted via a raised floor. The velocity of the flow of first air (filtered air introduced into the cleanroom) is 0.45 m/s. Environmental conditions in the cleanroom are kept constant with a room temperature of 22 °C ± 0.5 °C and a relative humidity of 45 % ± 5 %.

According to ISO 14644-1, Cleanroom Class 1 means that only ten particles the size of 0.1 µm may be found a reference volume of one cubic meter. In practical operation, even fewer particles are found in this cleanroom class.

4.3 Test set-up and parameters

Test set-up Memmert GmbH + Co. KG supplied Fraunhofer IPA with the test pieces. The test pieces were suitable for continuous, maintenance-free operation.

On delivery, the test pieces were introduced into the cleanroom at the Fraunhofer IPA in Stuttgart. They were then assembled and put into operation (complete with all the functional components required for its assembly and operation) by the customer.

Transfer of the test pieces into the cleanroom The test pieces were brought into the cleanroom. In doing so, all surfaces and other functional elements were first wiped clean with low particle emission cleanroom cloths soaked in a mixture of isopropanol and DI-water and then dried with a jet of ionizing purified compressed air.

Pre-conditioning the test pieces The test pieces were first operated in the reference cleanroom with a typical average load for a period of 24 hours while exposed to a flow of clean first air. In this way, the raised quantity of particles emitted during the running-in phase, which is not representative as far as later operation is concerned, is not included in the assessment.

Test parameters To determine particle emissions from the test pieces, they were operated using the parameters specified below.

The operating parameters selected for the test pieces were arranged with the customer before the start of the project:


TP01:

Temperature: .........................................................................................50° C

Humidity: .............................................................................................. 10 %

TP02:

Outside

Temperature: ....................................................................................... 300° C

Flap: .......................................................................................................open

Fan: ..................................................................................................... 100 %

Inside Parameter Set 1

Temperature: ....................................................................................... 300° C

Flap: .......................................................................................................open

Fan: ..................................................................................................... 100 %

Inside Parameter Set 2

Temperature: ....................................................................................... 300° C

Flap: .......................................................................................................open

Fan: ......................................................................................................... 0 %


Overview of the test set-up and test piece

Overview of the test set-up and test piece TP01 Figure 5

Overview of the test set-up and test piece TP02 Figure 6


4.4 Measuring equipment

In the tests to determine particle emissions, the following type of laser particle measuring device was used.

Type LasAir II 110 / LasAir III 110 from PMS with the measuring ranges of

0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm.

Optical particle counters function according to the principle of scattered light. Via a sampling probe, a defined volume of air of 1 cubic foot (1 cft = 28.3 liters) is sucked in every minute and guided into a measuring chamber via a tube connected to it. The air sucked in is illuminated by a light source - in modern devices either a laser or laser diode. As soon as a particle carried by the airflow is struck by the beam of light, light is scattered and recorded by photo-detectors.

The number of impulses recorded corresponds with the number of particles present in the volume of air. The amplitude of the impulses indicates the particle size.

4.5 Localization tests

To select the measuring points for the subsequent qualification tests, separate localization tests were performed for each set of parameters.

Critical contamination sites (these are generally areas subjected to tribological stress, such as bearings slits) were systematically investigated for particle emissions, taking into consideration the motion sequences planned. The surface of the test piece was also visually assessed. By comparing the values obtained, sites could be identified where especially high levels of particulate emission were generated during motion sequences. A particle measuring probe was carefully positioned at these sites to detect the maximum number of particles being emitted from the test object.


4.6 Qualification measurements

Procedure 4.6.1

The qualification tests were performed according to ISO 14644-14.

Measuring probes were placed at each of the critical sites identified (= measuring points). At each measuring point, particle emission measurements were recorded with measuring intervals of 1/min over a period of 100 minutes. To better compare results, up to 9 particle counters were used in parallel at up to 9 different measuring points for each test series to record particle emission values.

The measurement volume is sucked in at a rate of 1 cft/min. Particle measurements are shown cumulatively for each particle size channel, i.e. the figure shown for a particle size channel refers to all particles equal to or larger

than the particle size channel stated ( 0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm or 5.0 µm).

The selected time of 100 minutes ensures adequate statistical certainty of the test results and safeguards against faulty measurements. Each measurement value contains information about the particle size, the quantity of particles generated and the site where the particles were emitted.

The results were analyzed statistically conform to the procedure described in the guideline ISO 14644-14, thus enabling the suitability of the operating utility for use in cleanrooms classified according to ISO 14644-1 to be determined.


Test piece TP01: description of the measuring points MP01 to MP09 4.6.2

Outside

The following photographs show the exact points selected to measure airborne particles emitted from the test piece.

MP02

MP08

MP07

MP06

MP05

MP02 MP01 MP04

MP01

MP03


MP03

MP06 MP05

MP04


Measuring points MP01 to MP08 selected to measure airborne particle emissions from TP01 Figure 7

Inside

The following photographs show the exact point selected to measure airborne particles emitted from the test piece.

Measuring point MP09 selected to measure airborne particle emissions from TP01 Figure 8

MP09

MP08 MP07

MP09


Test piece TP02: description of the measuring points MP10 to MP19 4.6.3

Outside

The following photographs show the exact points selected to measure airborne particles emitted from the test piece.

MP11 MP10

MP18 MP17

MP16

MP15

MP14 MP13 MP12

MP11 MP10


Measuring points MP10 to MP18 selected to measure airborne particle emissions from TP02 Figure 9

MP18 MP15

MP14 MP13

MP12

MP17 MP16


Inside

The following photographs show the exact point selected to measure airborne particles emitted from the test piece.

Measuring point MP19 selected to measure airborne particle emissions from TP02 Figure 10

MP19

MP19


Analysis of the results from the airborne particle emission tests 4.6.4

The emission tests mentioned in Chapter 4.6.1 were analyzed according to ISO 14644-14. This included:

The course of particle emissions at each measuring point over time

Classification of the various measuring points according to ISO 14644-1 with

mean and maximum particle emission values

Course of particle emissions over time of TP01 4.6.5

The following diagrams show the course of particle emissions at each of the measuring points, as well as for the stated particle size channels, over the total testing time required by the qualification test. The measuring interval of 1 min was the same for all tests. This equates to a test volume of cubic foot (cft).

Outside 4.6.5.1

Occurrence of contamination over time:

Course of the emission of airborne particles 0.1 µm over time from the test piece at measuring points MP01 Figure 11to MP04 over the period of 100 minutes

0

20

40

60

80

100

120

140

160

0 10 20 30 40 50 60 70 80 90 100

Part

ike

l ≥

0,1

µm

pro

min

Messzeit [min]

Memmert GmbH + Co. KGConstant climate chamber HPP1060

OutsideMesspunkte MP01 bis MP04

Messpunkt MP01 Messpunkt MP02 Messpunkt MP03 Messpunkt MP04



Inside 4.6.5.2


Course of the emission of airborne particles 0.1 µm over time from the test piece at measuring point MP09 Figure 13over the period of 100 minutes

0

100

200

300

400

500

600

700

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in

Measuring time [min]


OutsideMeasuring Points MP05 to MP08

Measuring Point MP05 Measuring Point MP06 Measuring Point MP07 Measuring Point MP08

0

10

20

30

40

50

60

70

80

90

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in



InsideMeasuring Point MP09

Measuring Point MP09


Course of particle emissions over time of TP02 4.6.6

The following diagrams show the course of particle emissions at each of the measuring points, as well as for the stated particle size channels, over the total testing time required by the qualification test. The measuring interval of 1 min was the same for all tests. This equates to a test volume of cubic foot (cft).

Outside 4.6.6.1



0

200000

400000

600000

800000

1000000

1200000

1400000

1600000

1800000

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in


Memmert GmbH + Co. KGUniversal Oven UF1060


Measuring Point MP10 Measuring Point MP11 Measuring Point MP12



Course of the emission of airborne particles 0.1 µm over time from the test piece at measuring points MP17 Figure 16and MP18 over the period of 100 minutes

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

4500000

5000000

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in


Memmert GmbH + Co. KG Universal Oven UF1060


Measuring Point MP13 Measuring Point MP14 Measuring Point MP15 Measuring Point MP16

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in


Memmert GmbH + Co. KGUniversal Oven UF1060

OutsideMeasuring Points MP17 and MP18

Measuring Point MP17 Measuring Point MP18


Inside: Parameter Set 1 4.6.6.2






0

50000

100000

150000

200000

250000

300000

350000

400000

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in


Memmert GmbH + Co. KGUniversal Oven UF1060Inside - Parameter Set 1Measuring Point MP19


0

5000

10000

15000

20000

25000

0 10 20 30 40 50 60 70 80 90 100

Part

icle

s ≥

0.1

µm

pe

r m

in


Memmert GmbH + Co. KGUniversal Oven UF1060Inside - Parameter Set 2Measuring Point MP19



4.7 Classification

The aim of the tests was to ascertain to what extent the test piece may be operated in clean environments. For this, based on the procedure described in the guideline “Assessment of suitability for use of equipment by airborne particle concentration ISO 14644-14”, the empirically-calculated measurement values were analyzed statistically and assessed according to the class limits stated in ISO 14644-1.

Statistical verification of the test results 4.7.1

International standards defining air cleanliness, such as ISO 14644-1, state limit values for the air cleanliness classes that are defined in the respective norm. These limit values are set for a specific number of particle size channels (e.g.

0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm). When comparing empirically-derived values (e.g. from a qualification test) with such limit values, a certain degree of certainty is required by which the limit value may not be exceeded.

When classifying operating utilities, the standard deviation and mean values are calculated from the measurement values obtained. ISO 14644-14 describes a method which correlates these values with the limit values stated in ISO 14644-1. If a test piece is declared suitable for different classes, the assessment of the test piece is based on the highest class (worst-case assumption).


Mean and maximum particle emission values and classification of TP01 4.7.2

The following tables show the respective maximum values and arithmetical mean values of particle emissions recorded at the corresponding measuring points (MP) over the total testing time of 100 minutes. The applicable air cleanliness class according to ISO 14644-1 for each measuring point is highlighted.

Outside 4.7.2.1

Statistical characteristics of the measuring points MP01 to MP04 Figure 19

MP01 MP02 MP03 MP04

0.1 µm 0,1 0,8 45,2 0,0

0.2 µm 0,0 0,4 30,8 0,0

0.3 µm 0,0 0,3 26,3 0,0

0.5 µm 0,0 0,1 16,4 0,0

1.0 µm 0,0 0,0 4,5 0,0

5.0 µm 0,0 0,0 0,0 0,0

0.1 µm 0,4 1,0 17,9 0,1

0.2 µm 0,0 0,7 12,3 0,0

0.3 µm 0,0 0,7 11,8 0,0

0.5 µm 0,0 0,4 8,9 0,0

1.0 µm 0,0 0,1 3,2 0,0

5.0 µm 0,0 0,0 0,1 0,0

2 4 5 1

0.1 µm 3 5 137 1

0.2 µm 0 3 60 0

0.3 µm 0 3 56 0

0.5 µm 0 2 42 0

1.0 µm 0 1 14 0

5.0 µm 0 0 1 0

0.1 µm 0 0 21 0

0.2 µm 0 0 14 0

0.3 µm 0 0 9 0

0.5 µm 0 0 5 0

1.0 µm 0 0 0 0

5.0 µm 0 0 0 0

Maximum value

for the detection size

[particles / cft]

Minimum value


[particles / cft]

Memmert GmbH + Co. KG

Constant climate chamber HPP1060

Outside

Measuring Points MP01 to MP04

Statistical parametersMeasuring Point

Mean value


[particles / cft]

Standard deviation


[particles / cft]

Air Cleanliness Class [ISO 14644-1]



From the respective calculations for the detection sizes 0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm, it can be derived that the test piece is suitable for use in ISO Class 5 cleanrooms according to ISO 14644-1.

MP05 MP06 MP07 MP08

0.1 µm 36.7 5.5 288.8 41.8

0.2 µm 14.5 3.1 101.8 15.4

0.3 µm 5.0 2.3 27.5 8.0

0.5 µm 1.6 1.4 6.1 3.6

1.0 µm 0.5 0.4 1.8 1.0

5.0 µm 0.0 0.0 0.0 0.0

0.1 µm 35.7 3.4 237.9 30.0

0.2 µm 14.2 1.9 80.2 12.1

0.3 µm 5.3 1.5 17.4 7.7

0.5 µm 2.1 1.2 2.9 4.4

1.0 µm 0.9 0.6 1.5 2.2

5.0 µm 0.0 0.0 0.0 0.1

4 4 5 5

0.1 µm 99 19 631 148

0.2 µm 40 10 240 89

0.3 µm 18 7 66 73

0.5 µm 9 6 13 43

1.0 µm 5 3 7 21

5.0 µm 0 0 0 1

0.1 µm 0 0 7 4

0.2 µm 0 0 5 1

0.3 µm 0 0 4 0

0.5 µm 0 0 1 0

1.0 µm 0 0 0 0

5.0 µm 0 0 0 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Outside



Mean value


[particles / cft]

Standard deviation


[particles / cft]



Inside 4.7.2.2

Statistical characteristics of the measuring point MP09 Figure 21


Measuring PointMP09

0.1 µm 56,3

0.2 µm 34,6

0.3 µm 27,1

0.5 µm 12,5

1.0 µm 2,0

5.0 µm 0,0

0.1 µm 13,0

0.2 µm 7,4

0.3 µm 6,2

0.5 µm 4,1

1.0 µm 1,6

5.0 µm 0,0

5

0.1 µm 84

0.2 µm 55

0.3 µm 40

0.5 µm 21

1.0 µm 8

5.0 µm 0

0.1 µm 28

0.2 µm 15

0.3 µm 12

0.5 µm 4

1.0 µm 0

5.0 µm 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Inside


Statistical parameters

Mean value


[particles / cft]

Standard deviation


[particles / cft]



Mean and maximum particle emission values and classification of TP02 4.7.3

The following tables show the respective maximum values and arithmetical mean values of particle emissions recorded at the corresponding measuring points (MP) over the total testing time of 100 minutes. The applicable air cleanliness class according to ISO 14644-1 for each measuring point is highlighted.

Outside 4.7.3.1


MP10 MP11 MP12

0.1 µm 1140281,6 701000,4 729227,3

0.2 µm 24325,6 22389,4 23059,8

0.3 µm 615,3 478,1 522,9

0.5 µm 6,9 1,7 2,2

1.0 µm 2,4 0,6 0,7

5.0 µm 0,1 0,0 0,0

0.1 µm 176442,2 193234,3 206272,3

0.2 µm 7322,9 6929,3 7620,5

0.3 µm 283,5 238,1 273,4

0.5 µm 5,9 1,4 1,6

1.0 µm 2,5 1,0 0,8

5.0 µm 0,3 0,0 0,1

6 6 6

0.1 µm 1644537 1168431 1179773

0.2 µm 50339 47663 50962

0.3 µm 1706 1407 1521

0.5 µm 38 7 7

1.0 µm 17 6 3

5.0 µm 2 0 1

0.1 µm 762477 145659 168005

0.2 µm 6304 4132 4981

0.3 µm 213 94 120

0.5 µm 0 0 0

1.0 µm 0 0 0

5.0 µm 0 0 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]


Universal Oven UF1060

Outside



Mean value


[particles / cft]

Standard deviation


[particles / cft]




MP13 MP14 MP15 MP16

0.1 µm 3654759,7 2270022,9 2521813,3 2539319,5

0.2 µm 137578,9 84822,2 210076,2 146063,3

0.3 µm 5274,7 2736,8 5124,0 3672,9

0.5 µm 8,0 6,5 23,3 9,8

1.0 µm 1,7 1,5 6,3 1,6

5.0 µm 0,1 0,1 0,2 0,1

0.1 µm 291722,2 311028,3 387177,4 278084,1

0.2 µm 57014,0 35660,7 55735,2 57587,8

0.3 µm 3359,7 1785,0 2661,1 2433,5

0.5 µm 3,9 2,7 10,0 4,1

1.0 µm 1,6 1,4 3,8 1,8

5.0 µm 0,3 0,3 0,4 0,3

5 5 5 5

0.1 µm 4333045 3063254 3682757 3245531

0.2 µm 342433 220982 371127 372329

0.3 µm 15881 9206 14532 12250

0.5 µm 27 13 59 30

1.0 µm 8 6 23 11

5.0 µm 2 2 2 2

0.1 µm 2848188 1486632 1816745 1835586

0.2 µm 59065 35137 110059 63258

0.3 µm 1292 619 1692 768

0.5 µm 2 1 9 3

1.0 µm 0 0 0 0

5.0 µm 0 0 0 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Outside



Mean value


[particles / cft]

Standard deviation


[particles / cft]



Statistical characteristics of the measuring points MP17 and MP18 Figure 24

From the respective calculations for the detection sizes 0.1 µm, 0.2 µm,

0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm, it can be derived that the test piece is suitable for use in ISO Class 6 cleanrooms according to ISO 14644-1.

MP17 MP18

0.1 µm 2220777,6 2020629,7

0.2 µm 128841,2 95005,7

0.3 µm 1125,9 390,6

0.5 µm 139,5 31,0

1.0 µm 49,1 11,3

5.0 µm 1,8 0,2

0.1 µm 358518,1 676581,7

0.2 µm 32870,2 30094,7

0.3 µm 307,1 153,1

0.5 µm 43,0 11,7

1.0 µm 19,1 5,5

5.0 µm 1,5 0,5

6 6

0.1 µm 3097062 3389622

0.2 µm 211405 190805

0.3 µm 1969 1068

0.5 µm 356 71

1.0 µm 135 30

5.0 µm 7 2

0.1 µm 1582323 684823

0.2 µm 58834 40857

0.3 µm 610 164

0.5 µm 71 10

1.0 µm 23 3

5.0 µm 0 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Outside

Measuring Points MP17 and MP18


Mean value


[particles / cft]

Standard deviation


[particles / cft]






Measuring PointMP19

0.1 µm 160206,6

0.2 µm 1061,8

0.3 µm 15,5

0.5 µm 2,0

1.0 µm 0,4

5.0 µm 0,0

0.1 µm 89848,2

0.2 µm 581,7

0.3 µm 5,5

0.5 µm 1,7

1.0 µm 0,7

5.0 µm 0,1

6

0.1 µm 361057

0.2 µm 2901

0.3 µm 30

0.5 µm 10

1.0 µm 4

5.0 µm 1

0.1 µm 10034

0.2 µm 64

0.3 µm 5

0.5 µm 0

1.0 µm 0

5.0 µm 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Inside - Parameter Set 1



Mean value


[particles / cft]

Standard deviation


[particles / cft]






Measuring PointMP19

0.1 µm 17914,2

0.2 µm 1,3

0.3 µm 0,0

0.5 µm 0,0

1.0 µm 0,0

5.0 µm 0,0

0.1 µm 1641,1

0.2 µm 1,2

0.3 µm 0,0

0.5 µm 0,0

1.0 µm 0,0

5.0 µm 0,0

6

0.1 µm 22323

0.2 µm 5

0.3 µm 0

0.5 µm 0

1.0 µm 0

5.0 µm 0

0.1 µm 14705

0.2 µm 0

0.3 µm 0

0.5 µm 0

1.0 µm 0

5.0 µm 0

Maximum value


[particles / cft]

Minimum value


[particles / cft]



Inside - Parameter Set 2



Mean value


[particles / cft]

Standard deviation


[particles / cft]



4.8 Summary of the classification results

TP01

The following table gives an overview of the classification of the various measuring points MP01 to MP09:

Constant climate chamber HPP1060 manufactured by Memmert GmbH + Co. KG

Outside

Measuring Point MP01 MP02 MP03 MP04

Air Cleanliness Class (according to ISO 14644-1)

2 4 5 1

Measuring Point MP05 MP06 MP07 MP08


4 4 5 5

Inside

Measuring Point MP09 -- -- --


5 -- -- --

Overall classification of the constant climate chamber HPP1060 Figure 27

From the calculations of the probability of exceeding limiting values for the

detection sizes 0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm, it can be derived that the constant climate chamber HPP1060 manufactured by Memmert GmbH + Co. KG is suitable for use in cleanrooms fulfilling the specifications of ISO Class 5 in accordance with ISO 14644-1 when operated with the specified parameters.


TP02

The following table gives an overview of the classification of the various measuring points MP10 to MP19:

Universal Oven UF1060 manufactured by Memmert GmbH + Co. KG

Outside

Measuring Point MP10 MP11 MP12 MP13 MP14


6 6 6 5 5

Measuring Point MP15 MP16 MP17 MP18 --


5 5 6 6 --

Inside: Parameter Set 1

Measuring Point MP19 -- -- -- --


6 -- -- -- --

Inside: Parameter Set 2

Measuring Point MP19 -- -- -- --


6 -- -- -- --

Overall classification of the Universal Oven UF1060 Figure 28

From the calculations of the probability of exceeding limiting values for the

detection sizes 0.1 µm, 0.2 µm, 0.3 µm, 0.5 µm, 1.0 µm and 5.0 µm, it can be derived that the Universal Oven UF1060 manufactured by Memmert GmbH + Co. KG is suitable for use in cleanrooms fulfilling the specifications of ISO Class 6 in accordance with ISO 14644-1 when operated with the specified parameters.


4.9 Annex: comparison of different classifications of airborne particulate

contamination

In the following table, the limit values defining air cleanliness classes according to the international standard ISO 14644-1 are compared with the limit values stated in EG GMP Guideline Volume 4 Annex 1 and in the American norm US Federal Standard 209E (retracted). The comparison concerns the particle size channels stated explicitly in ISO 14644-1; limit values are stated for the reference volumes of 1 m3 and 1 cft (1 cubic foot = 0.0283 m3).

Overview of limit values for airborne particles per m³ or cft for the standards ISO 14644-1, Figure 29

EU GMP Guideline Volume 4, Annex 1 and US Federal Standard 209E (retracted)

Although limit values are stated for tests on biotic airborne particles in EU GMP Guideline Volume 4, Annex 1, this does not form part of the qualification tests conducted at Fraunhofer IPA. Since all manufacturing environments have their own individual germ spectrum, these tests cannot be conducted in a reference laboratory and therefore need to be performed in the respective manufacturing environment. The individual germ spectrum and magnitude of microbial loads are decisively influenced by the production processes, the environment and operating staff in the relevant production areas.

1 10 0,3

2 100 3 24 1 10 0,3

3 1,000 30 237 7 102 3 35 1

1 1,240 35 265 8 106 3 35 1

4 10,000 300 2,370 67 1,020 29 352 9,9 83 2

10 12,000 340 2,650 75 1,060 29 353 10

5 100,000 2,833 23,700 671 10,200 289 3,520 100 832 24

A 3,520 100 20 0,6

A 3,520 100 20 0,6

B 3,520 100 29 0,8

100 26,500 750 10,600 300 3,530 100

6 1,000,000 28,329 237,000 6,710 102,000 2,890 35,200 997 8,320 235 293 8

1,000 35,300 1,000 247 7

7 352,000 9,972 83,200 2,357 2,930 83

B 352,000 9,972 2,900 82

C 352,000 9,972 2,900 82

10,000 353,000 10,000 2,470 70

8 3,520,000 99,716 832,000 23,569 29,300 830

C 3,520,000 99,716 29,000 821

D 3,520,000 99,716 29,000 821

100,000 3,530,000 100,000 24,700 700

9 35,200,000 997,167 8,320,000 235,694 293,000 8,300

per

[m³]

per

[cbf]

per

[m³]

per

[cbf]

per

[m³]

per

[cbf]

per

[m³]

per

[cbf]

US Fed.

Standard

209E*

DIN EN

ISO

14644-1 per

[m³]

per

[cbf]

per

[m³]

per

[cbf]

Regulatory

0.2 μm 0.5 μm 1.0 μm 5.0 μm

Limiting values of each Air Cleanliness Class for differing particle sizes and reference volumes

(acc. to ISO 14644-1)

0.1 μm 0.3 μmEG-GMP

"in

operation"

EG-GMP

"at

rest"

Documents

Cleanliness suitability and cleanroom suitability tests at