ASHRAE Journal - November 2019 - 39

ASHRAE - CELEBRATING 125 YEARS

Contamination and Contamination Control
Contamination is an impurity, or some other undesirable
element, that soils, infects, makes unfit, or makes inferior
a material, a physical body, a natural environment, a
workplace, a product, etc. The contamination may be
viable, such as bacteria, microbes or viruses, or it may be
in the form of nonviable particles such as metals, organic
or inorganic compounds, pollution or dust. Airborne
contamination may also be gaseous or molecular contamination. Contamination may be brought into a space
by people, materials and equipment and/or airborne
contaminants located outside the space. Controlling contamination in a space is accomplished in two major ways:
prevention of contamination from entering the space
and prevention of contamination generated within the
space from contaminating a person, product or material.
People, equipment and materials can be cleaned prior
to their introduction into the space. Proper filtration
and the use of positive pressure can mitigate airborne
contamination.

Hospitals
Hospitals were the first spaces to attempt to control the
air where patients were located. Controlling the ventilation of hospital spaces was seen in first-century Roman
military hospitals. Over the centuries, hospitals were
large, open halls that were well heated and ventilated.
Florence Nightingale made dramatic improvements in
the mortality rates of wounded soldiers by insisting on
scrupulously clean, well-ventilated hospital rooms.2
Louis Pasteur is remembered for his breakthrough in
the causes and prevention of diseases. His medical discoveries provided direct support for the germ theory of
disease and its application in clinical medicine. Pasteur
performed experiments that showed that without contamination, microorganisms could not develop. He
demonstrated that in sterilized and sealed flasks, nothing ever developed, and in sterilized but open flasks,
microorganisms could grow.3
The control of infection during surgery was a significant driver to controlling contamination. Early pioneers
included British surgeon and advocate of antiseptic
surgery Joseph Lister, who pioneered the use of disinfectants; American surgeon William Keen and his efforts at
cleaning the surgical suite; and German Gustav Neuber,
who in 1883 designed a "cleanable" surgical suite containing nonporous surfaces, glass and metal furnishings

and in-room sterilization equipment. Neuber-style
surgery suites were adopted in many locations.4 These
early innovations provided guidance to manufacturers
also concerned with controlling contamination in their
precision manufacturing operations.

Precision Manufacturing and Contamination Control
Many manufacturers understood the need to keep particles out of the products they were building. Increased
cleaning was an obvious solution, but preventing the
particles from entering the space proved more challenging. Contamination in the manufacturing process
results in defects and unfit products. Precision manufacturing operations, such as watch making and ball
bearing manufacturing, were early adopters of contamination control techniques and the need to clean materials and have clean workstations.
In the latter part of the 1800s, Aaron Dennison and
Edward Howard relocated their watch factory from
downtown Roxbury/Boston, where traffic on unpaved
roads was disastrous to the precise watch parts, to the
suburbs of Waltham to avoid the heavy dust. During
World War II the need for more precise military parts
increased the demand for clean manufacturing environments. Precision bearings were used in gyroscopes and
bomb sites before and during World War II.4
After the war the U.S. military continued to develop
advanced aircraft with advanced guidance systems
and miniature parts. 1947 saw the invention of the first
transistor, and by the mid 1950s The New York Times spoke
about 'the business of making things smaller' as central
to new aircraft performance. Two years later Time magazine hailed miniaturization as a key to business growth;
acknowledging that military needs drove the trend, it
forecast that 'miniaturization will in time spread through
civilian U.S. life.' Already, pocket radios, tiny hearing aids
and other electronic devices had grown smaller; in the
future, so too would 'giant electronic brains.' 4

Early Cleanrooms
Similar to surgery suites, manufacturers needed a
special room where they could control contamination. Constant cleaning, while effective, was not very
productive. Manufacturers of precision military products started to request designs for "ultra-clean" rooms
and "white rooms" (or cleanrooms). Some claim that
Western Electric's "dust-free" room built in 1955 was the
N O V E M B E R 2 0 19

ashrae.org

ASHRAE JOURNAL

39


http://www.ashrae.org

ASHRAE Journal - November 2019

Table of Contents for the Digital Edition of ASHRAE Journal - November 2019

Contents
ASHRAE Journal - November 2019 - Intro
ASHRAE Journal - November 2019 - Cover1
ASHRAE Journal - November 2019 - Cover2
ASHRAE Journal - November 2019 - 1
ASHRAE Journal - November 2019 - Contents
ASHRAE Journal - November 2019 - 3
ASHRAE Journal - November 2019 - 4
ASHRAE Journal - November 2019 - 5
ASHRAE Journal - November 2019 - 6
ASHRAE Journal - November 2019 - 7
ASHRAE Journal - November 2019 - 8
ASHRAE Journal - November 2019 - 9
ASHRAE Journal - November 2019 - 10
ASHRAE Journal - November 2019 - 11
ASHRAE Journal - November 2019 - 12
ASHRAE Journal - November 2019 - 13
ASHRAE Journal - November 2019 - 14
ASHRAE Journal - November 2019 - 15
ASHRAE Journal - November 2019 - 16
ASHRAE Journal - November 2019 - 17
ASHRAE Journal - November 2019 - 18
ASHRAE Journal - November 2019 - 19
ASHRAE Journal - November 2019 - 20
ASHRAE Journal - November 2019 - 21
ASHRAE Journal - November 2019 - 22
ASHRAE Journal - November 2019 - 23
ASHRAE Journal - November 2019 - 24
ASHRAE Journal - November 2019 - 25
ASHRAE Journal - November 2019 - 26
ASHRAE Journal - November 2019 - 27
ASHRAE Journal - November 2019 - 28
ASHRAE Journal - November 2019 - 29
ASHRAE Journal - November 2019 - 30
ASHRAE Journal - November 2019 - 31
ASHRAE Journal - November 2019 - 32
ASHRAE Journal - November 2019 - 33
ASHRAE Journal - November 2019 - 34
ASHRAE Journal - November 2019 - 35
ASHRAE Journal - November 2019 - 36
ASHRAE Journal - November 2019 - 37
ASHRAE Journal - November 2019 - 38
ASHRAE Journal - November 2019 - 39
ASHRAE Journal - November 2019 - 40
ASHRAE Journal - November 2019 - 41
ASHRAE Journal - November 2019 - 42
ASHRAE Journal - November 2019 - 43
ASHRAE Journal - November 2019 - 44
ASHRAE Journal - November 2019 - 45
ASHRAE Journal - November 2019 - 46
ASHRAE Journal - November 2019 - 47
ASHRAE Journal - November 2019 - 48
ASHRAE Journal - November 2019 - 49
ASHRAE Journal - November 2019 - 50
ASHRAE Journal - November 2019 - 51
ASHRAE Journal - November 2019 - 52
ASHRAE Journal - November 2019 - 53
ASHRAE Journal - November 2019 - 54
ASHRAE Journal - November 2019 - 55
ASHRAE Journal - November 2019 - 56
ASHRAE Journal - November 2019 - 57
ASHRAE Journal - November 2019 - 58
ASHRAE Journal - November 2019 - 59
ASHRAE Journal - November 2019 - 60
ASHRAE Journal - November 2019 - 61
ASHRAE Journal - November 2019 - 62
ASHRAE Journal - November 2019 - 63
ASHRAE Journal - November 2019 - 64
ASHRAE Journal - November 2019 - 65
ASHRAE Journal - November 2019 - 66
ASHRAE Journal - November 2019 - 67
ASHRAE Journal - November 2019 - 68
ASHRAE Journal - November 2019 - 69
ASHRAE Journal - November 2019 - 70
ASHRAE Journal - November 2019 - 71
ASHRAE Journal - November 2019 - 72
ASHRAE Journal - November 2019 - 73
ASHRAE Journal - November 2019 - 74
ASHRAE Journal - November 2019 - 75
ASHRAE Journal - November 2019 - 76
ASHRAE Journal - November 2019 - 77
ASHRAE Journal - November 2019 - 78
ASHRAE Journal - November 2019 - 79
ASHRAE Journal - November 2019 - 80
ASHRAE Journal - November 2019 - 81
ASHRAE Journal - November 2019 - 82
ASHRAE Journal - November 2019 - 83
ASHRAE Journal - November 2019 - 84
ASHRAE Journal - November 2019 - 85
ASHRAE Journal - November 2019 - 86
ASHRAE Journal - November 2019 - 87
ASHRAE Journal - November 2019 - 88
ASHRAE Journal - November 2019 - Cover3
ASHRAE Journal - November 2019 - Cover4
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VJKSRY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDHUTC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JPPKRR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDLTTH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CKLLES
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SLDOX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_HJETUK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OLUHGE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ZERDGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QVMNEO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTPOKE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_BBATRE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_STUBMW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TPEMPE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JNMKDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FBTTPA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WQMMNE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TVBRYN
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2020
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_KTUZMA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ABEDGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201910
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201909
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019septmeber_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019september
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201908
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201907
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201906
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201905
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201904
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019april
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201903
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019march
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201902
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201901
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2019
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018december
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018october
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2018
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201810
https://www.nxtbook.com/nxtbooks/ashrae/ashraeinsights_201806
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201805
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201804
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201803
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201712
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201711
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201710
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201709
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201705
https://www.nxtbook.com/nxtbooks/ashrae/ashrae_meetinginsert_201610
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acrexindia
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer
https://www.nxtbook.com/nxtbooks/amca/2014summer2
https://www.nxtbook.com/nxtbooks/amca/2014summer
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acma_2014summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201311
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201309
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acmasupp_2013fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201305
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201303
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2013winter
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201211
https://www.nxtbook.com/nxtbooks/ashrae/achr_expo_mexico2012
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201209
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v3
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201205
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201203
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012winter
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201111_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201109_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2011summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201105
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201103
https://www.nxtbookmedia.com