Theatre Design & Technology - Summer 2017 - 41

raise concerns about exposure. For other resins used in
casting, local exhaust is required for the vapors and gases
emitted. So, it is reasonable to assume that users should
work with an exhaust system when handling resin and uncured prints from an SLA machine.
Manufacturers of plastic can also be vague with their
SDS sheets, because they don't know how consumers will
ultimately use the products. For example, the ARGOS
PLA Filament SDS only recommends: "Ventilation: Necessary to exclude dust, fumes and gases." In all cases, it is
imperative that the users of the plastic educate themselves
on the hazards and assume responsibility for their own
safety.
Safer Machines: In 2012, a leading manufacturer of
3D printers, StrataSys, hired an independent laboratory
to conduct air quality measurements of its various models
of FFF Printers. It is important to note that the StrataSys printers use an enclosed printing space that is heated;
thus, the operator is not exposed to all the emissions during printing. Also, these 3D printers have specifically designed a venting and filtering system that reduces airborne
chemicals outside the printer (Figure 2). The lab found
that the level of airborne particles were below the specified
PELS and TLVs with this particular unit design. While
the measurable amounts of particles are within safe limits, there is still a recognizable odor when these machines
are in use. This odor is based on a limitation in the filters
used. High-Efficiency particulate air (HEPA) filters are
designed to stop 99% of particles that are 0.3 μm or larger.
This can deal with dusts created from sanding, grinding or
other physical abrasion. But, for the smaller particles inside
fumes, there is no guarantee of capture.
For artists and companies that cannot afford the more
expensive machines, there are a few options, including
commercial solutions that are made for extracting fumes.
BOFA Americas Inc. is the American arm of BOFA Ltd
UK, which has been manufacturing fume extraction and
filtration solutions since 1987. For example, one of their
products involves a cabinet with an air intake that pulls
air through the cabinet into the filtering mechanism. This
creates negative pressure in the cabinet, so there is only
one direction the fumes can go (Figure 3). At Washington and Lee University, the design lab repurposed an existing exhaust system from an unused darkroom to create
a similar arrangement. The 3D printers are housed in a
purpose-built cabinet with negative pressure that vents
directly to the outside (Figure 4). It uses ductwork that
is separate from the room's HVAC. The negative pressure
in the cabinet and separate ductwork prevents the fumescontaminated air from being circulated into the room. This
was built by university facilities to the specifications of a
HVAC specialist who was familiar with fume extraction
and cost significantly less than purchasing a BOFA sys-

tem, primarily because of the existing ductwork that already fit the necessary local exhaust requirements.
When we are on the forefront of a new technology, our regulations can lag behind. 3D printing provides
a good example of why users need to put more thought
into the chemicals and toxins that are produced by new
technologies. A careful reading of the Safety Data Sheets
provided by the manufacturers of filament and resins will
provide only some of the necessary information on the
safe practice and usage of 3D printers, but as discussed,
these sheets are also impacted by delays and incomplete
information. OSHA and ACGIH can provide additional
information, but remember that when looking into safety
concerns, the only person that is looking out for the user
is you. Manufacturers are not required to disclose, and indeed they may not know, all of the hazards to which the
user may be exposed. And just because you feel fine now,
that doesn't mean that recurring exposure to fumes and
chemicals from 3D printing will not adversely impact your
health in the future. The time to act is now. Establish safety
protocols and systems to guarantee that your health and
creativity will not be affected later.
Owen Collins MFA is a professor of theatre
at Washington and Lee University, where he
has taught since 2002 and was department
head for 8 years. Collins was the artistic
director of the Ensemble Theatre Community
School, where he was also a faculty member for 12 years.
His design work has been seen at The Ailey Citigroup
Theatre, the Corcoran Gallery of Art, and Lucille Lortel
Theatre, as well as other venues in the Unites States. Reach
him by email at owenmcollins@gmail.com or on Twitter @
owenscenic.

WORKS CITED

Dennekamp, M. et al. 2001. "Ultrafine particles and nitrogen oxides generated by
gas and electric cooking." Occupational and Environmental Medicine 58.8: 511-16.
Rossol, Monona. 2011. The Health and Safety Guide for Film, TV, and Theater. 2nd
Ed. New York: Allworth Press.
Rossol, Monona. 2016. "SDS Info & Comments: Section By Section." Arts Crafts
Theater Safety Data Sheet Revised 07/02/2016.
Rossol, Monona. 2016. "Threshold Limit Values Data Sheet" Arts Crafts Theater
Safety Data Sheet Revised 07/02/2016.
United States Department of Labor. Occupational Safety and Health Administration.
"Permissible Exposure Limits - Annotated Tables." Accessed 21 February 2017.
https://www.osha.gov/dsg/annotated-pels/tablez-1.html
United States Department of Labor. Occupational Safety and Health Administration.
"Ventilation." OSHA Technical Manual. Section III, Chapter 3. Accessed 23 May
2017. https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_3.html

S u m m e r   2 0 1 7

theatre design

& technology

41


https://www.osha.gov/dsg/annotated-pels/tablez-1.html https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_3.html

Table of Contents for the Digital Edition of Theatre Design & Technology - Summer 2017

Contents
Theatre Design & Technology - Summer 2017 - Cover1
Theatre Design & Technology - Summer 2017 - Cover2
Theatre Design & Technology - Summer 2017 - 1
Theatre Design & Technology - Summer 2017 - 2
Theatre Design & Technology - Summer 2017 - Contents
Theatre Design & Technology - Summer 2017 - 4
Theatre Design & Technology - Summer 2017 - 5
Theatre Design & Technology - Summer 2017 - 6
Theatre Design & Technology - Summer 2017 - 7
Theatre Design & Technology - Summer 2017 - 8
Theatre Design & Technology - Summer 2017 - 9
Theatre Design & Technology - Summer 2017 - 10
Theatre Design & Technology - Summer 2017 - 11
Theatre Design & Technology - Summer 2017 - 12
Theatre Design & Technology - Summer 2017 - 13
Theatre Design & Technology - Summer 2017 - 14
Theatre Design & Technology - Summer 2017 - 15
Theatre Design & Technology - Summer 2017 - 16
Theatre Design & Technology - Summer 2017 - 17
Theatre Design & Technology - Summer 2017 - 18
Theatre Design & Technology - Summer 2017 - 19
Theatre Design & Technology - Summer 2017 - 20
Theatre Design & Technology - Summer 2017 - 21
Theatre Design & Technology - Summer 2017 - 22
Theatre Design & Technology - Summer 2017 - 23
Theatre Design & Technology - Summer 2017 - 24
Theatre Design & Technology - Summer 2017 - 25
Theatre Design & Technology - Summer 2017 - 26
Theatre Design & Technology - Summer 2017 - 27
Theatre Design & Technology - Summer 2017 - 28
Theatre Design & Technology - Summer 2017 - 29
Theatre Design & Technology - Summer 2017 - 30
Theatre Design & Technology - Summer 2017 - 31
Theatre Design & Technology - Summer 2017 - 32
Theatre Design & Technology - Summer 2017 - 33
Theatre Design & Technology - Summer 2017 - 34
Theatre Design & Technology - Summer 2017 - 35
Theatre Design & Technology - Summer 2017 - 36
Theatre Design & Technology - Summer 2017 - 37
Theatre Design & Technology - Summer 2017 - 38
Theatre Design & Technology - Summer 2017 - 39
Theatre Design & Technology - Summer 2017 - 40
Theatre Design & Technology - Summer 2017 - 41
Theatre Design & Technology - Summer 2017 - 42
Theatre Design & Technology - Summer 2017 - 43
Theatre Design & Technology - Summer 2017 - 44
Theatre Design & Technology - Summer 2017 - 45
Theatre Design & Technology - Summer 2017 - 46
Theatre Design & Technology - Summer 2017 - 47
Theatre Design & Technology - Summer 2017 - 48
Theatre Design & Technology - Summer 2017 - 49
Theatre Design & Technology - Summer 2017 - 50
Theatre Design & Technology - Summer 2017 - 51
Theatre Design & Technology - Summer 2017 - 52
Theatre Design & Technology - Summer 2017 - 53
Theatre Design & Technology - Summer 2017 - 54
Theatre Design & Technology - Summer 2017 - 55
Theatre Design & Technology - Summer 2017 - 56
Theatre Design & Technology - Summer 2017 - 57
Theatre Design & Technology - Summer 2017 - 58
Theatre Design & Technology - Summer 2017 - 59
Theatre Design & Technology - Summer 2017 - 60
Theatre Design & Technology - Summer 2017 - 61
Theatre Design & Technology - Summer 2017 - 62
Theatre Design & Technology - Summer 2017 - 63
Theatre Design & Technology - Summer 2017 - 64
Theatre Design & Technology - Summer 2017 - 65
Theatre Design & Technology - Summer 2017 - 66
Theatre Design & Technology - Summer 2017 - 67
Theatre Design & Technology - Summer 2017 - 68
Theatre Design & Technology - Summer 2017 - Cover3
Theatre Design & Technology - Summer 2017 - Cover4
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019fall_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019summer_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019spring_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/usitt_techexpoguide_2019_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/usitt_techexpoguide_2019
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019winter_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2019winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018fall_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018summer_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018spring_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2018winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017fall_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017summer_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017spring_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/usitt_techexpoguide_2017_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/usitt_techexpoguide_2017
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017winter_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2017winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2016fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2016summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2016spring_public
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2016spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2016winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2015fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2015summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2015spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2015winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2014fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2014summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2013winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2013summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2013fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2013spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2012winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2012fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2012summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2012spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2011winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2011fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2011summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2011spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2010winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2010fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2010summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2010spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2009winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2009fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2009summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2009spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2008winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2008fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2008summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2008spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2007winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2007fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2007summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2007spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2006winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2006fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2006summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2006spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2005winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2005fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2005summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2005spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2004winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2004fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2004summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2004spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2003winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2003fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2003summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2003spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2002winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2002fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2002summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2002spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2001winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2001fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2001summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2001spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2000winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2000fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2000summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_2000spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1999winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1999fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1999summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1999spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1998winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1998fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1998summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1998spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1997winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1997fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1997summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1997spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1996winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1996fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1996summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1996spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1995winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1995fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1995summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1995spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1994winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1994fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1994summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1994spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1993winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1993fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1993summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1993spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1992winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1992fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1992summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1992spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1991winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1991fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1991summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1991spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1990fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1990summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1990spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1989winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1989fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1989summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1989spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1988winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1988winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1988fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1988summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1988spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1987winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1987fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1987summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1987spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1986winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1986fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1986summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1986spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1985winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1985fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1985summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1985spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1984fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1984summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1984spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1983winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1983fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1983summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1983spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1982winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1982fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1982summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1982spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1981winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1981fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1981summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1981spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1980winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1980fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1980summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1980spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1979winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1979fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1979summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1979spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1978winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1978fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1978summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1978spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1977winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1977fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1977summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1977spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1976winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1976fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1976summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1976spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1975winter
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1975fall
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1975summer
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1975spring
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1974Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1974Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1974May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1974Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1973Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1973Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1973May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1973Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1972Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1972Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1972May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1972Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1971Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1971Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1971May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1971Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1970Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1970Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1970May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1970Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1969Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1969Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1969May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1969Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1968Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1968Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1968May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1968Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1967Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1967Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1967May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1967Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966May
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966Feb
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965Dec
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965Oct
http://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965May
http://www.nxtbookMEDIA.com