Waste Management in Space
The Space Program has changed quite a bit in the past few decades and the waste
management system is no different, evolving from what now is considered a primitive
disposal systems meant for short-term missions to more and more advanced and high-
tech systems that have long-term space flight, such as a mission to Mars, in mind. Just as
with any space-related topic, the issue of microgravity comes up with waste management
It‟s amazing how much our bodies and everyday lives depend on gravity. For
example, in a microgravity environment defecation becomes a much more difficult and
complicated task than it is here on earth. Our paper will get into more detail regarding
this topic later; however, just for a gist of things and something to think about(too much
jargon, we are writing here, not talking): it requires somewhere around 45 minutes for an
astronaut to go through the process of defecation and cleanup in space, a significant
change in time compared to that here on earth. Another annoying consequence of
microgravity is that wipes(what are wipes) occupy up to 3 times as much space as they do
here on earth, which leads to a buildup of waste if not dealt with properly as one can
imagine. Also in space urination volumes tends to increase; therefore, an appropriate
containment and disposal system must be put in place to take into account this increase in
volume. The need for this system has risen significantly in years since it is no longer
economical to bring back all of the waste from a space mission back to earth, especially
since long-distance space missions are looking more and more like a reality. In our
paper, we hope to address all these issues as well as giving a general history and
evolution of the waste management system during EVAs and in the shuttle as well.
INTROuction: The function of the waste management system (WMS) is to organize the
disposal and recycling of solid and liquid wastes. The basic requirements of the system
include the collection and stowage of feces, the collection and recycling of urine, and the
removal of urine from the pressure garment assembly. The waste management system
consists of a urine subsystem and a fecal subsystem. Starting first with the urine
subsystem, the principal elements are the urine receptacle assembly (URA), the urine
transfer system (UTS), the urine collection and transfer assembly, (UCTA), and special
urine collection devices that are used to collect samples for postflight analysis. The most
important component of this subsystem is the recycling of the water in urine. If it is not
obvious, one just has to think about it for a few moments and realize(jargon) that since
resources are scarce during space missions, everything needs to be conserved and reused
if possible. This is no different with water, and considering that water is one of the most
used and necessary resource for the sustenance of human life it is very important that if
transportation of needed water is not economical, then a reliable recycling system must
be put in place. Therefore, every drop of water, even the water in waste materials, must
be reused in the spacecraft as well as during EVAs, which we will go into further detail
Based on the waste-management system of the Apollo missions, the primary
means of urine purification is by a method that is termed, Multi-filtration. Just as a side
note(stop it!) the Russians also use this „multi-filtration‟ method for their urine
processing. This process is termed multi-filtration (MF) because there are several steps
involved. The first step is termed „pretreatment‟ and is required to stabilize urine for
microbial control. The next step is the distillation/ evaporation process used to lower the
urine‟s salt content. Afterwards OxoneO (a potassium monopersulfate compound) and
sulfuric acid are added to the urine stream in appropriate quantities so that the urine‟s
ammoniated species may be stabilized. This is very important since during urea
hydrolysis, ammonia gas is produced which is poisonous and therefore, must be kept
away from the cabin air.
Here is a picture of the urine collection device used in Apollo missions:
After the „pretreatment‟ process is complete, the urine enters the primary
purification system. In most systems used today, the first step involves the removal of
particulate material by some mode of filtration. In the next step, dissolved salts and
organics are removed by absorption onto a combination of ion exchange resins, activated
carbons, and other various media. Alcohol and urea are not effectively destroyed by
adsorption, thus they require additional treatment via catalytic oxidation. Many chemicals
can perform this oxidation step such as PCC (Pyridinium Chlorochromate) or some
Magnesium oxide compound (KMNO4 or MNO2-). The Russians and the Americans
employ slightly different techniques in this final oxidation step. The Russian system uses
ambient temperature catalysts, whereas the Americans use a low-temperature aqueous
phase catalytic oxidation reactor, termed the Volatile Removal Apparatus (VRA).(Good
comparison) (So, can you drink the water now? Is this the entire process?) Another
system that is currently being tested in parallel to Multi-filtration is the vapor
compression distillation system (VCD). The VCD processes pretreated urine and flush
water by a phase change process. The original stream of pretreated urine is evaporated at
low pressure to form water vapor and then the vapor is compressed in order to increase its
pressure and condensation temperature. The vapor is then redirected to the condenser
where the vapor condenses and produces latent heat, which is transferred to provide heat
for evaporation. In order to measure the water‟s purity, the VCD contains a conductivity
sensor that measures the conductivity of the product water. If its conductivity exceeds
120 mmho/cm, the water goes through another cycle of purification in the VCD.
Concentrate and other pollutants are collected in a tank within the VCD. See Appendix D
Urination Time and Flow Rate Chart: (What is this? Why don’t you talk about it?)
Equipment used prior to the Apollo missions functioned very similarly to the ones
used during the Apollo missions with a few minor design changes. Before the start of
Apollo 12, the astronauts utilized the urine transfer system (UTS). The urine transfer
system consists of a roll-on cuff, a receiver, a valve with a manifold, a collection bag, and
a quick-disconnect fitting. The roll-on cuff was a rubber tube that functioned as an
external catheter between the penis and the receiver/valve. The cuff was designed to be
used for one day (five or six urinations) and was then replaced.
Beginning with Apollo 12 and missions thereafter, a different system was used
called the urine receptacle assembly (URA). The urine receptacle assembly is an open-
ended, cylindrical container that can be conveniently held. The receptacle is connected by
a quick-disconnect fitting attached to a flexible urine dump line, which in turn is
connected by a quick-disconnect fitting attached to the waste management panel. The
receptacle can accommodate a maximum urine flow of 40 ml per second. The URA
contains a honeycomb cell insert that supports a hydrophilic screen. The honeycomb
insert provides a large contact area that acts as a bundle of capillary tubes. The capillary
action produced by each cell of the honeycomb tends to hold the fluid in place in the
microgravity environment until it can pass into the urine dump line.
During the Apollo launches, EVAs, and emergencies, the shuttle crew(but Apollo
is not a shuttle) would wear a device known as the urine collection and transfer assembly
(UCTA) (FIG2). The urine collection device accommodated a maximum urine output of
4000mL per person per day with a maximum discharge rate of 800mL per urination and
at a delivery rate of 50mL/sec. The device was worn over the LCG, not the LCVG, since
it did not exist yet.(good insight) The urine collection and transfer assembly is designed
to facilitate urination when crewmen are wearing pressure suits such as during EVAs.
The urine collection and transfer assembly consists of a roll-on cuff and a collection
bladder worn around the waist. The UCTA is worn over the fecal containment garment.
Urine in the device can be drained either while the crewmen are in the suit, or after the
suit is removed by connecting the urine transfer hose to the spacecraft waste management
The urine transfer hose is made of flexible, convoluted fluorocarbon, which
allows it to withstand the pressure difference between the spacesuit and the spacecraft,
and at same time be supple enough for the astronauts to easily manage during EVAs. The
hose also can be used to join the space suit‟s urine quick-disconnect fitting to the waste
management panel in order to expedite the removal of urine from the collection
assembly. Installed between the waste management panel quick-disconnect fitting and
the hose is a 215-micrometer filter, used as prevention against the clogging of the hose
with use over time. The dump nozzle orifice has a diameter of 0.1397 cm, which restricts
liquid flow to 453.6 gm/minute.
The Urinary and Transfer Assembly (Yes, I know it is a picture)
Because no system existed to extract feces from the body, the men had to rely
upon the most basic concept for “inflight fecal collection.” The method involved using
tape to adhere a plastic bag to the buttocks to catch the fecal excretion(when was this?).
The other primary component of the waste management system is the fecal subsystem(Is
this the new system). As stated before, this system usually consists of a fecal collection
assembly, tissue dispensers, a waste stowage compartment, and a waste storage bag. The
fecal collection assembly consists of a fecal bag and an outer fecal/emesis (FE) bag
bound together with a plastic wrapper. The fecal bag is a plastic sack with a flange at the
opening and a finger cot in the center of one side. A stretch of tape is used to attach the
flange to the buttocks. Tissue wipes and a germicide pouch are stored in a pocket on the
outside lower end of the bag. The outer transparent FE bag is used for storing of the used
fecal bag. Internal and external seals at the mouth of the bag make it capable of
containing a 3.4 x 104-N/m2 (5 psi) gas differential pressure. The fecal collection system
generally functions in the following way: The finger cot(what is a finger cot anyway?) is
used to position the fecal bag over the anus. After the astronaut discharges their bodily
waste, the bag is removed from the buttocks, and the anus is cleaned with tissue wipes.
The wipes are also disposed of into the fecal bag. The user secures the germicidal liquid
pouch and cuts the corner off the outer pouch. The user then deposits the germicide into
the outer pouch and seals the bag. The germicidal liquid is often a mixture of sodium
orthophenylphenol and sodium chlorophenylphenol of amaplast blue LXT. The inner
pouch is then ruptured in order to mix the germicide with the wastes. The inner bag is
then placed into the outer bag. The whole thing is then rolled into the smallest possible
volume and then placed in the waste stowage compartment. This compartment features a
split membrane inside the door to prevent fecal bags from floating back out into the cabin
once they had been placed within the compartment.
During extravehicular activity, a fecal containment system (FCS) is also
employed. This FCD consists of a pair of underpants of absorbent material worn under
the LCVG. If an uncontrolled bowel movement occurs, the underpants will contain the
Table 2 (SEE APPENDIX B) shows the averages of sample weight of fecal matter
obtained for analysis on the Apollo missions. Carmine red and brilliant blue dyes were
given orally to the subjects for separation of stool periods. Preflight and postflight
collections were carried out using toilet facilities established in the crew quarters and at
various sites where the crew was undergoing training and preparation. Orbital stool
collections were made with specially designed inflight plastic defecation bags. The entire
sample was stored in the cabin without refrigeration but with a mixture of
phenylphenolate derivatives in propylene glycol as a preservative. This data could be
used to analyze the overall diet of the individual, how much water the person is losing per
day, tell if the person has any sickness, etcetera.
Table 3 (SEE APPENDIX C) contains data that summarizes which devices were
worn during each Apollo mission. The first known spaceflight which involved the usage
of an actual toilet was in 1973 during the age of Skylab. The area was probably as small
as the size of a bathroom stall now and did not include a sink or shower.
Experimental Fecal/Emesis System Flown Aboard Apollo 16
Three modified fecal collection bags were flown to evaluate their performance on the
Apollo 16 mission. The bags were of the same basic design as the Gemini-type(where did
you talk about this?) fecal bag with the following exceptions: (1) a modified seat flange,
for better fit of seat flange to buttocks (this helped with the comfort issue that most
crewmen had with the device); (2) a wider finger cot; and (3) and improved seal for
keeping the device closed during performance of personal hygiene (with the improved
seal, there was less chance of contact with the waste by accidental escape).
Lunar Module Waste Management System
The Lunar Module waste management system incorporated systems used in the
Command Module. These systems were used in similar fashion in both the Lunar Module
and Command Module. The principal difference was that there was no overboard
dumping of wastes on the lunar surface. The urine subsystem in the Lunar Module
consisted of in-suit urine containers (identical to the Command Module system), a urine
transfer hose, a manually operated waste control valve, and a large (8900 cm3) waste
fluid container. To drain the in-suit device, the waste fluid container was attached to the
in-suit urine container by a urine transfer hose, and the suit was then slightly
overpressurized. Because of a 6.9 x 103-N/m2 (1.0 psi) pressure differential, when the
control valve opened urine flowed from the in-suit container to the waste fluid container
at a rate of approximately 200 cm3/minute. As a backup device, two 900-cm3 waste
containers were provided for direct attachment to the in-suit container. On Apollo 15 and
subsequent missions, a low pressure container was installed in the descent stage of the
Lunar Module. A line interconnected this tank with a urine receiver in the ascent stage.
This receiver was a simple funnel-like receptacle that permitted urine collection without
In general, the Apollo waste management system worked satisfactorily from an
engineering standpoint. From the point of view of crew acceptance though, the system
was seen as unsatisfactory. The greatest concern with both the urine and fecal collection
systems was the fact that these required more manipulation than crewmen were used to in
the Earth environment and were, as a consequence, found to be objectionable. The urine
receptacle assembly represented an attempt to preclude crew handling of urine specimens
but, because urine spills were frequent, the objective of "sanitizing" the process was
thwarted. The fecal collection system caused the most distasteful set of problems. The
collection of the feces required much skill to prevent the waste from eluding the
collection bag and consequently soiling the crew, their clothing, or cabin surfaces. The
difficulty of the fecal collection process caused a large consumption of time. An Apollo
7 astronaut required an estimated time of 45 minutes[*] to correctly accomplish the
process. Good placement of fecal bags was difficult to attain; this was further
complicated by the fact that the flap at the back of the constant wear garment created an
opening that was too small for easy placement of the bags.[**] As stated earlier, kneading
of the bags was required to release the germicide within the bag for inactivation of the
Attempts to improve the fecal collection system, as exemplified by the modified
fecal/emesis collection bags flown on Apollo 16, failed in the crew‟s estimation. During
Postflight debriefings, crew comments indicated that the experimental bag was not
significantly better or easier to use than the baseline Gemini-type bag. Further
development of the bag was, therefore, not pursued.
The Apollo waste management system‟s design and operations pointed to the need for
several improvements in future missions. These were the following:
1. Future systems should not require intimate contact.
2. The time required for system use should be significantly reduced.
3. The waste management system should provide some technique of automatically
removing feces from the buttocks area.
These considerations were taken into account in the design of the improved Skylab waste
Considerations for waste control on EVA and on the ship were the following
during the Skylab period: comfort, user-acceptable (often less intimate contact with the
materials; example to follow in discussing fecal matter containment), be able to last the
duration of EVA (6-8hours), safely be able to use without attendants (no other person
would have to be present as when people originally donned and doffed), ease of use, post
defecation cleansing, volume and mass of body waste products. Defecation is unlikely to
occur so the system should provide urine and menses protection for women, urine support
for men, and containment of defecation in case of diarrheal episodes.
Table 1 (See Appendix A) shows the mass and volumes of everyday human waste
By analyzing this data, it is very possible to develop the devices necessary to
contain the waste. We must look at the mass and volume of the waste produced to utilize
the proper materials to contain the waste. They must be able to contain the specific
volume particularly. Mass is not such a large concern since microgravity can deal with
the weight in space. Normal fecal bolus of a healthy adult ranges from 4-8 inches long by
.5-1.5 inches in diameter and weighs anywhere from 3.5-7oz.
Figure 4 Urination Time and Flow Rates
*Microgravity tends to increase the volume of urine excreted per day. This means we
should account for the increased volume such that we are not venting urine out of the
shuttle. One of the problems that occurred during the lunar optical experiments was that
the dumped waste tended to form a cloud of vapor around the shuttle that would interfere
with the observations and damage the optical equipment. So to properly develop devices,
we must also consider the physiological changes in flow rate of urine, menses (for
women), size of fecal boluses, the number of times that each person urinates or defecates
to minimize bags required to dump the waste.
Waste Management Facility Design
The STS urination and defecation facility contains the following features, which have
a. Restraints - The following restraints are provided in the facility:
1. Spring loaded thigh bars that press the user against the opening used for defecation.
2. Footstraps to stabilize the body for clean up after defecation.
b. Urine collectors - Funnels at the end of a suction tube are used to collect urine only
(without defecation). For males, a straight conical funnel approximately 7.6 cm (3 in)
long and 5.4 cm (2-1/8 in) in diameter (at the large end) was selected as optimum. For
females, an oval funnel was developed which had angled air inlet openings to give a
vortex action to the airflow. Each crewmember has a personal collector.
c. Supplies - The compartment is arranged so that cleanup supplies can be readily
accessed. These supplies should include gloves, dry and wet wipes, tissues, germicidal
agents, etc. The overall layout is shown below.
Layout of the STS Waste Management Station
In the past, during EVAs, urine was collected in male astronauts via a disposable
urethane-coated nylon bag. This UCD (urine collection device) was connected to their
bodies by velcro fasteners and a harness. For female astronauts a super-absorbent diaper,
MAG (Maximum Absorbent Garment) was worn. The MAG consists of five different
layers; the plastic outer liner, the coform absorbent material, the water absorbent layer,
the nonwoven layer, and the tricot liner. The plastic layer, as the outer most layer,
prevents excess liquid from leaving the garment. Immediately under this is the coform
absorbent layer. The coform absorbent layer is the layer that allows the MAG to conform
to the body for a secure fit and to allow some absorption.
However, most of the absorption occurs in the gel layer. This layer consists of
tightly packed sodium polyacrylate crystals. These crystals have a distinct shape, due to
hydrogen bonding, that keeps them in a condensed shape. As water ( a protic substance
that contains hydrogen bonds) enters the crystals, the shape immediately changes. The
hydrogen bonds are broken, and the sodium atom leaves the acrylate group causing the
anionic oxygen to carry a negative charge. This causes the molecule to flatten out and
allows water groups to lie in between layers of crystals. Due to their high molecular
weight, the crystals do not completely dissolve in the water and instead form a gel layer
that will not be uncomfortable to the astronaut.
Below this layer is a one way woven layer that allows the gel layer to slide over
the final tricot layer. Tricot is a soft layer of material that gently hugs the body giving a
stretch tight security, yet doesn‟t restrict movement while sleeping or any other activity.
This thermal wrap effectively traps warmth allowing the person to also stay warm.
Additionally, vaseline was once used to create a layer between the person and the MAG
to prevent diaper rash. Now, the UCD and the MAG are worn over the LCVG, reducing
the need for a vasoline layer. The UCD and MAG is shown below respectively.
-Find a method such that we can disinfect the waste and recycle it for usage as fertilizer.
This would work extremely well on a Mars colony or long term mission. This would aid
in self-sustaining habitats by fertilizing plants to be eaten. Another possibility is to send
the waste generated from urine through a disinfecting area (although urine should already
be sterile), cool it, use it for LCVG, pass it through PLSS to filter out the excess minerals
and then send it through for drinking water.
-The MAG, which is the present device, works quite well in terms of absorbency, but it is
limited by the ability to only take on liquids. Also, if anyone drinks a lot of fluids, the
person‟s MAG cannot support more than 32 fluid ounces so the urine would overflow.
This is a bigger problem for women in case of the need to urinate and possibly
menstruate in the same EVA. (A simple solution for the menstruating issue is to use
female hormones that prevent the woman from menstruating for several months. I think
they already do this)) The volume, which can be seen in FIG 3 contains enough fluid to
possibly cause overflow of the MAG, which could lead to some real discomfort. For
long duration space travel, this is not as practical as it may seem.
- One of the main issues concerning the fecal management system is the significant
amount of space that is required to store the used fecal bags. On many of the Apollo
missions, the volume provided by the waste stowage compartment was inadequate. Our
group feels that this problem can be resolved if the fecal matter is dehydrated and burned
instead of stored. Storage space is a valuable commodity on the shuttle and we feel that
designing a unit to eliminate the wastes will be advantageous in the long run. One section
of the unit would consist of water reclamation system that would completely dry out the
fecal matter and transfer the recovered water back into the purification unit. The second
part of the unit would consist of a „burning chamber‟ that would exist in a closed
atmosphere separate from the rest of the shuttle. The chamber would be composed of air
with approximately 20% oxygen (to simulate conditions on Earth). The fecal matter will
then enter this chamber and undergo a combustion reaction producing CO2 and water as
byproducts. The carbon dioxide would be absorbed by lithium hydroxide canisters, which
would eventually be disposed of. Our group feels that this unit will be very profitable
addition to the space shuttle because it will eliminate the need for a waste stowage
Conclusion: Although no official deadline for achieving human travel to Mars has been
set, scientists say that this mission is imminent. “Let's burn it into our brains that in our
lifetimes, we will extend the reach of these human species onto other planets and onto
other bodies in our solar system," said Daniel Golden, director of the U.S. National
Aeronautics and Space Administration (NASA). 1
While many scientists say that a mission to Mars is technologically possible, there
are many questions as to whether it is practical, economic, or safe to undertake such a
mission. This interplanetary flight will take us 136 million to 150 million miles from
Earth, thus it will require astronauts to travel in space for at least a few years. This
extended length of space travel time that is required means that every element of the
shuttle and space suit should be functioning as efficiently as possible. The waste
management system is one of the most vital components of the space shuttle because the
astronauts must interact with it several times a day. Constructing a more efficient water
recovery and fecal disposal system is an extremely important consideration when
evaluating the space shuttle because a more resourceful, fine-tuned waste management
system will greatly extend the duration of time that astronauts can spend in space, which
will eventually enable us to travel to farther destinations.
WASTE PRODUCTS MASS (gm/person/day) VOLUME
Hair growth 0.03 (0.3 to 0.5 mm per
Mensus (see note 1) 113.4 113.4
Flatus as gas - 2000
WASTE PRODUCTS MASS (gm/person/day) VOLUME
Solids in feces 20 19
Water in feces 100 100
Solid in urine 70 66
Water in urine (note 2) 1630 1630
1. Approximately once every 26 to 34 days and lasts 4 to 6 days, approximately 80%
released during first 3 days.
2. Based on Skylab data
-Jeff & Arul: Responsible for background research of the paper and organization of the
-Ray: Responsible for organization of the presentation.
-Liz: Responsible for editing paper
4/2- checked VLSB for waste removal info
4/4- went to engineering library to search for other methods to find information on
campus, called NASA AMES to check library. Got no response.
4/11- worked on putting pictures into the paper
4/14- met to work on the paper
Group Member Tasks
-Jeff – research EVA urine and defecation devices, look up history, help compile the
paper data, find pictures for history, presentation
-Arul – research water purification systems on the space shuttle, find out details about the
fecal bag, organize and found pictures for presentation.
-Ray –researched renal stone formations and urinary monitoring system as well as
helping out in the compilation of the final paper and organization of the paper
-Liz -Completed research on the MAG and current systems
Aided in editing of paper
(had some problems completing some work due to motorcycle accident)
Plan to Acquire Information
- interview someone in the field
- explore the NASA archives
- internet research
- search NASA AMES library
-Could not reach NASA AMES Library
-Difficult to find materials in campus libraries
-Difficult to find faculty with any background
In this 3rd project on waste removal, I found myself swamped by how much there
was to do on the project. I attempted to manage the group such that I organized times to
get everyone to meet. I was not assigned this, but I tried my best to make sure that
everyone was on track. This involved calling and e-mailing the other members to check
what they had done by the allotted time and having to find a meeting place to congregate.
I made sure that everyone had each other‟s contact information.
Next, I researched information on the internet as well as worked with Arul in
trying to attain access to the Ames Research Center Library. I worked on finding
research on the LCVG, MAG, URA, UTS, at the Valley Life Sciences Building library
and at the Bechtel library, but they did not involve space relevant data. Compiling the
photos and data for the paper was completed by Arul and me. Part of the work was
proof-reading the paper, putting the pictures in the proper place, I worked on the power
point slides to approve what would be good points to exemplify, organized the logical
order of the presentation, found pictures and presented a portion of the presentation on
the EVA involved waste system.
For this project, I, Arul Krishnan, was responsible for researching the basic ideas
behind water reclamation and fecal management on the space shuttle. I did some general
research and decided what areas our group needed to focus its research on. With what I
found from my research, I also determined what aspects of waste management were the
most difficult to find.
For the report, I wrote about the processes through which urine was recycled and
how fecal matter was stored. I also researched the specific things that could be improved
upon with these processes.
During the presentation, I spoke several different parts of the urine receptacle
assembly and how the MAG functioned. I also explained some our group‟s ideas on how
the waste management system can function more efficiently. I also contributed some
graphs to our presentation, but we ended up using only one of them due to time
constraints. In addition to my part in the paper and the presentation, I was also present at
all of my groups‟ meetings and assisted in assigning everyone duties.
Liz Hulsey (one page summary)
-Completed research on the MAG and current systems
-Aided in editing of paper
-(had some problems completing some work due to motorcycle accident)
Since our topic covers a wide range of issues, we were all forced to do extensive
research and then meet up and decide which topics we would keep and delve into. I
researched issues ranging from renal stone formation and urinary monitoring systems, to
the effects of microgravity on the human body in terms of urination and defecation.
Although I did find significant information regarding renal stone formation and urinary
monitoring systems, we felt as a group that these topics did not relate to our overlying
theme of waste-management, and so we left them out of our paper. However, the said
topics are very relevant and if we had more time, I would love to do more research on
them. Nevertheless, our paper topic was finalized, which leads us to the presentation.
Once again my services were called to hand, and I gladly accepted.