Ch. 12 Filter Installation Leak Testing. HEPA test Manufacturer's factory and packed OK Unpacked...
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Transcript of Ch. 12 Filter Installation Leak Testing. HEPA test Manufacturer's factory and packed OK Unpacked...
HEPA test HEPA test
Manufacturer's factory and packed Manufacturer's factory and packed OKOK
Unpacked and fitted into the filter housingsUnpacked and fitted into the filter housings maybe damage maybe damage
Leakage problems Leakage problems – casingcasing– housinghousing
Testing : artificial test aerosol Testing : artificial test aerosol
Leakage areas in a HEPA filter
A - filter paper-to-case cement area C- gasketD - frame joints. B - filter paper (often at the paper fold)
Gasket leaks from filters inserted down from ceiling
Gasket and casing leaks from filter inserted up from cleanroom
Artificial Smoke and Particle Test Artificial Smoke and Particle Test
Cold-generated oilsCold-generated oils– Di-octyl phthalate (DOP)Di-octyl phthalate (DOP) 鄰苯二甲酸二辛酯鄰苯二甲酸二辛酯
oily liquid, potentially toxic effects, no longer used oily liquid, potentially toxic effects, no longer used
– Di-octylsebacate (DOS)Di-octylsebacate (DOS) 葵二酸二辛酯葵二酸二辛酯常用常用
– poly alpha olefin (PAO)poly alpha olefin (PAO) 聚烯茎油 聚烯茎油 常用常用
Cold-generated oil Test Cold-generated oil Test
Laskin nozzleair (high pressure)
oil
Air+oil particle
0.5 m
Air pump
Hot generated smokesHot generated smokes
Evaporation chamber
inert gas: CO2
oil
oil smoke
aerosol
condense
vaporize
0.3 m
Semiconductor manufacturing Semiconductor manufacturing
'outgassing' 'outgassing'
chemical products harmful to filter chemical products harmful to filter
使用使用 Polystyrene Latex Spheres (PLSs)Polystyrene Latex Spheres (PLSs)
聚苯乙烯乳膠球聚苯乙烯乳膠球 (0.1 ~ 1(0.1 ~ 1m)m)
Apparatus for Measuring Smoke Apparatus for Measuring Smoke PenetrationPenetration
PhotometerPhotometer 光度計光度計– 28 1/min (1 ft3/min) of airbor28 1/min (1 ft3/min) of airbor
ne particles ne particles – particles refract the light particles refract the light – electrical signalelectrical signal– concentration: between 0.00concentration: between 0.00
01 μg/1 and 100 μg/1. 01 μg/1 and 100 μg/1.
Single particle countSingle particle countersers– sample a volume of aisample a volume of ai
r and this is collected r and this is collected in a set timein a set time
Methods of Testing Filters and Methods of Testing Filters and Filter HousingsFilter Housings
Scanning methodsScanning methods– a probe with a photometer, or single particle a probe with a photometer, or single particle
counter, counter, – Scan speed : not more than 5cm/sScan speed : not more than 5cm/s– leaks : media, filter case, its housing leaks : media, filter case, its housing – The most common leaks: The most common leaks:
around the periphery of the filteraround the periphery of the filter
the casing-to-housing seal, the casing-to-housing seal,
the casing jointsthe casing joints