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Experiments / Smoke diagnostics

DAFTSupports fire safety

Dust and Aerosol Measurement Feasibility Test

Checked that a commercial particle counter still works without gravity, so that the SAME smoke measurements could be trusted.

NASA's own record
An astronaut works with the DAFT instrument beside a foil bag on the space station.
Astronaut Jeffrey Williams works with DAFT, August 2006. NASA photograph iss013e69250.

What burned

Nothing was burned

It tested an instrument, not a flame

Where

On the space station

In orbit, where everything is weightless

How much data

2 test days

NASA's table lists days, each with several flames

What they changed between tests

  • instrument
  • sampling location

What it found

  1. The counter normally relies on gravity to recycle its working fluid, so it had to be modified and proven before SAME could use it.

    NASA's words

    “there were concerns that th P-Trak would not be reliable in microgravity as it relies on gravity to recycle isopropyl alcohol used in the measurement process” PSI record

Summarized by the SI. Each summary is tied to a quotation that the build checks against NASA's text. A matching quote is not a scientific review.

What it helps with

  • Stopping a fire from starting

    Which materials burn, and in what air

    Not an aim

  • Noticing a fire early

    What smoke looks like to a detector

    A clear part

  • Putting a fire out

    What makes a flame go out

    Not an aim

For researchers: NASA's full recordThe conditions tested, every row of the table, NASA's description, publications and hardware
ISSMicrogravity InvestigationSmoke diagnosticsCompare with othersdoi:10.60555/ztgj-d202

Shared hardware: Particle counters and smoke detectors; one of the instruments was first proven in a dust test. Experiments that shared hardware share its limits, so their results can be compared directly.

Why it counts as fire-safety research

“One of the instruments used for smoke detection in the SAME and SAME-R studies was instead used to detect dust in the Dust and Aerosol Measurement Feasibility Test (DAFT and DAFT-2) studies.” NASA challenge statement

NASA's words behind each rating

  • Prevention0 of 3

    Not an aim of this investigation.

  • Detection2 of 3

    “This research will impact the development of novel fire and smoke detection systems for the International Space Station and future spacecrafts.”

  • Suppression0 of 3

    Not an aim of this investigation.

Conditions covered

Oxygen in the atmosphere
not reported
not in the PSI table
Pressure
not reported
not in the PSI table
Flow speed
not reported
not in the PSI table
Itemized rows
6
4 tests, 2 test days

Fuels and materials

ISS cabin air (3), Arizona Road Dust (Fine) (3)

Measurements named in the PSI record

  • Aerosol counters

How the tests differ, and how they are the same

Worked out from the 6 rows of the PSI table. A variable that is not listed was not reported, which is different from being held fixed.

Changed from test to test

Fuel or material
2 different values
Particle number concentration (P-Trak)
1.43 particles/cm³ to 26,578 particles/cm³reported in 4 of 6 rows
Particle mass concentration (DustTrak)
33.8 mg/m³ to 62.7 mg/m³reported in 3 of 6 rows
Mass per particle (DustTrak mass over P-Trak count)
2.04e-12 g to 2.65e-12 greported in 3 of 6 rows
Particle diameter from the mass per particle (assumed density)
1.57 µm to 1.72 µmreported in 3 of 6 rows

The same in every test

No variable has the same value in every row.

Reported for only some rows, with one value: geometry.

Rows from the PSI table

Click a row for the source of every value. Filter and export

RecordTypeFuel or materialShapeOxygenPressureFlow, cm/sOutcomeDate
DAFT-3 Sample Bag #1 (GMT 233, 2006)TestArizona Road Dust (Fine)not reportednot reported2006-08-21
DAFT-3 Sample Bag #2 (GMT 233, 2006)TestArizona Road Dust (Fine)not reportednot reported2006-08-21
DAFT-3 Sample Bag #3 (GMT 233, 2006)TestArizona Road Dust (Fine)not reportednot reported2006-08-21
DAFT-3 Session D3, cabin air (GMT 229, 2006)TestISS cabin airnot reportednot reported
Session D1Test dayISS cabin airdust aerosol (no flame)not reportednot reported2005-02-22
Session D2Test dayISS cabin airdust aerosol (no flame)not reportednot reported2005-03-04
How the table was read, and what was repaired

Tests added from other NASA files (PSI-47)

PSI-47_Evidence pack_PSI-47

4 rows in the file, 4 kept as records. These tests are not in PSI's experimental table. They were read from other NASA files, which are named on each value.

sha256 · fetched 2026-11-13

DAFT - instrument sessions

PSI-47_Experimental table_DAFT.csv

2 rows in the file, 2 kept as records. Instrument checkout with a dust aerosol standard. No combustion took place.

sha256 d9d1a436c6e7bbc410b433e04575fe7dedaff763b5237d688089929b7393b5c0 · fetched 2026-11-11

Repairs and warnings

  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 17236.3 particles/cm³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 17314.3 particles/cm³ (Voice Down Data Summary!B21). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 17236.3 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 17314.3 particles/cm³ (Data!C23). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 17236.3 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 17314.3 particles/cm³ (Data!B21). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 16589.4 particles/cm³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 17256.2 particles/cm³ (Voice Down Data Summary!E21). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 16589.4 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 17256.2 particles/cm³ (Data!G23). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 16589.4 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 17256.2 particles/cm³ (Data!E21). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 26578 particles/cm³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 24350 particles/cm³ (Voice Down Data Summary!H21). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 26578 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 24350 particles/cm³ (Data!K23). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 26578 particles/cm³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 24522.2 particles/cm³ (Data!H21). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 45.6343 mg/m³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 43.15 mg/m³ (Voice Down Data Summary!C21). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 45.6343 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 43.15 mg/m³ (Data!D23). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 45.6343 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 43.15 mg/m³ (Data!C21). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 33.8377 mg/m³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 34.0875 mg/m³ (Voice Down Data Summary!F21). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 33.8377 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 34.0875 mg/m³ (Data!H23). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 33.8377 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 34.0875 mg/m³ (Data!F21). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 62.6509 mg/m³; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 63.1833 mg/m³ (Voice Down Data Summary!I21). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 62.6509 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 63.1833 mg/m³ (Data!L23). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle mass concentration (DustTrak): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 62.6509 mg/m³; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 63.2889 mg/m³ (Data!I21). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.71639 µm; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.68213 µm (Voice Down Data Summary!B25). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.71639 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 1.68213 µm (Data!C27). The first is the one used.
  • DAFT-3 Sample Bag #1 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.71639 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 1.68213 µm (Data!B25). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.57347 µm; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.55674 µm (Voice Down Data Summary!E25). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.57347 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 1.55674 µm (Data!G27). The first is the one used.
  • DAFT-3 Sample Bag #2 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.57347 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 1.55674 µm (Data!E25). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.65121 µm; NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.70491 µm (Voice Down Data Summary!H25). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.65121 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_0611zgy time hist.xls gives 1.70491 µm (Data!K27). The first is the one used.
  • DAFT-3 Sample Bag #3 (GMT 233, 2006), Particle diameter from the mass per particle (assumed density): NASA's file PSI-47_Analyzed Data_DAFT Retrieved Data Summary.xls gives 1.65121 µm; NASA's file PSI-47_Analyzed Data_ISS_Daft_Aug21_06 urban.xls gives 1.70186 µm (Data!H25). The first is the one used.
  • Session D1, Particle number concentration (P-Trak): NASA's file PSI-47_Analyzed Data_DAFT Flight Data GMT053.xls gives 1.43189 particles/cm³; NASA's file PSI-47_Reports_DAFT_FinalReport.doc gives 2 to 5 particles/cm³ (section II.D.1 (DAFT-1 & DAFT -2, Session 1, GMT 54, 2005)). The first is the one used.

NASA's description

Objectives

The focus of DAFT / DAFT-2 was to mitigate the risk for the Smoke Aerosol Measurement Experiment (SAME). SAME relied on a commercially available condensate nuclei counter, the TSI P-Trak, to quantify smoke aerosols in a microgravity environment, however there were concerns that th P-Trak would not be reliable in microgravity as it relies on gravity to recycle isopropyl alcohol used in the measurement process. DAFT / DAFT-2 tests that a modified P-Trak particulate counter would be accurate in microgravity. Summarized objectives include: 1) Demonstrate the Functionality of the Modified TSI P-Trak in Microgravity 2) Compare the TSI P-Trak Performance against the DustTrak control 3) Create and Analyze Aerosol Standards in Microgravity 4) Ensure the reliability of future aerosol experiments

Approach

The experimental approach consists of the following components: 1) Modification of Instrumentation: TSI P-Trak was modified for use in microgravity by redesigning the condenser tube to use capillary forces for recycling isopropyl alcohol and removing the mercury switch responsible for detecting instrument orientation. 2) Aerosol Generation: Arizona Red Dust (ARD) was chosen as an aerosol standard due to its ease of dispersion. The ARD was aerosolized with GN2 to create particle samples. The aerosol was contained within 15-liter Mylar bags. 3) On-Orbit Testing: The modified P-Trak gathered data from counting aerosol particles and these data were compared to the DustTrak CNC specifically designed to work in microgravity.

Hypothesis

The TSI P-Trak operates by condensing isopropanol around aerosol particulates that are subsequently laser counted. It was hypothesized that the P-Trak would not work in microgravity due to two potential failure modes that exist. 1) the system would clog or become obscured by isopropanol, and 2) the internal air-flow dynamics of the optics chamber of the device will cause an over counting of particulates. The TSI P-Trak was modified for microgravity use via using capillary action to recycle the isopropanol. Therefore, there are two basic hypotheses: 1) that the P-Trak, as modified for use in SAME, would function normally in microgravity. 2) that the aerosol created and filtered per the experiment design would be within the measurement capabilities of the test devices.

Research impacts and Earth benefits

Extended duration space flight missions with larger vessels will require fire detection systems with increased reliability and sensitivity. This research will impact the development of novel fire and smoke detection systems for the International Space Station and future spacecrafts. Additionally, the successful adaptation of the TSI P-Trak for microgravity can inform the design of instruments for use in other challenging Earth environments, such as submarines or underwater laboratories where accurate detection of smoke can save lives.

Publications

2 listed in PSI, 2 with a DOI.

  1. A Research Plan for Fire Prevention, Detection and Suppression in Crewed Exploration SystemsRuff Gary, Urban David, King Merrill
  2. Detection of Smoke from Microgravity FiresUrban David, Griffin DeVon, Ruff Gary, Cleary Thomas, Yang Jiann, Mulholland George, Yuan Zeng-guang

Hardware and raw data

41.8 MB of raw data on PSI: reports 3, raw data 6, metadata 1, analyzed data 12, presentations 3, engineering documents 6, representative image(s) 1. FlameLens reads the experimental table, not the raw video or sensor files.

Linked investigations

On Earth

Smoke detection: The modified instrument design carries over to other sealed environments.

“such as submarines or underwater laboratories where accurate detection of smoke can save lives”