• Group 2 Radon Measurement Mitigation (part 1) Discuss the following issues: 1. What is Radon? (best to include discussion on types of radiation) 2. Where does Radon come from? (source of Radon) 3. Why are we interested in Radon? 4. Radon testing and Radon gas measurement method

1. Group 2
Radon Measurement Mitigation (Part 1)
Group members:
• Muhammad Ramdhan Hidayat (SEM130702)
• Ibnu Syafiq Imaduddin (SEM150702)
• Amirah binti Basir (SIF170004)
• Amirul Auzan bin Kasilawati (SIF170005)
• Anis Zulaikha binti Ridzuwan (SIF170007)
• Atifah Damia binti Talha (SIF170008)
• Nur Risha binti Md Rashid (SIF170036)
• Nur Syamimi binti Kamaruddin (SIF170037)

2. Overview
1. What is
Radon?
2. Where is
Radon come
from?
3. Why are
we
interested in
Radon?
4. Radon testing
and Radon gas
measurement
method

3. Decay of Uranium

4. What is Radon?
Radioactive Tasteless
Colourless Odourless
> Noble gas with characteristics of:

5. How can Radon gas
lead to lung cancer?
Decay of Uranium will produce Radon
Decaying Radon emits alpha particle, beta
particle and gamma ray
The emitted radiation lead to lung cancer

6. Emission from decaying Radon
Type of radiation
Size of particle
emitted
Energy Penetration
Alpha particle Large Lot Poor
Beta particle Small Little Medium
Gamma ray Very small Little High

7. Effect Of Emission
Alpha particle
• Damage is concentrated on
the epithelial cells in the
immediate area
• Damage the chromosomes
(DNA) and other type of
cellular damage
Beta particle and gamma ray
• They are spread over a
larger volume causing less
concentrated and less
harmful

8. WHERE DOES RADON COME FROM?
Soil and air
Water
Natural gas
Homes and Buildings

9. Soil and Air
Radon generated within the upper few metres of
the Earth’s crust by the radioactive decay of
Radium. So, it is a common element found in
rock and soil.
Radon in soil can be partitioned into 3 states – in
the pore air, dissolved in the pore air and
absorbed to the soil grains.
Breathing Radon in indoor air can cause lung
cancer.

10. Water
Concentration of Radon in water from wells higher than from
surface sources
Groundwater tends to have more direct and longer contact with
rocks and soil
Most of the radon volatizes to air or decays before the water reaches
homes results in a small amount of residual radon
Drinking water containing Radon will risk in developing internal organ
cancer, primarily stomach cancer.

11. Natural Gas
 Natural gas had previously been in contact with underground
uranium and thorium-bearing rock and soil that continually
release radon.
 Radon and its progeny are released to breathing air when the
gas is burned in
 Fireplaces
 Furnaces
 Heaters
 Stoves
 Water heaters

12. Homes and Buildings
RADONCANENTERTHEHOME
THROUGH
Diffusion from the ground
Pressure-driven flow of air in the home ( such as
fireplace, kitchen, bathroom )
Water supply, especially from private wells
Gas appliances

13. WHY ARE WE INTERESTED IN
RADON?
1. Radon is everywhere
around us:

14. Example: Radon in houses
Radon can enter the home through
1. Cracks in solid floors
2. Construction joints
3. Cracks in walls
4. Gaps in suspended floors
5. Gaps around service pipes
6. Cavities inside walls
7. Water supply

15. 2) Radon is a cancer-
causing radioactive gas
 Radon is carcinogenic to humans due to alpha
particle emission.
 Evidence:

16. RADON TEST AND
RADON GAS
MEASUREMENT
METHODS
RADON TEST
• METHOD: GAS
MEASUREMENT

17. RADON TEST
• What is Radon test?
• The test conducted to determine the Radon level in
a building; home
• Detect Radon or daughter of Radon radioactive
decay
• Who can do the test?
• A qualified professional radon testing service
(recommended by U.S. Environmental Protection
Agency (EPA))
• By ourselves – buy test kit
• When the test should be done?
• Home with passive Radon system, test immediately
after moving in
• Recommended average annual indoor level of
Radon by EPA: ≤ 4.0 pCi/L
• Where to test it?
• Lowest occupied level; greatest level of radon
may occur
• Frequently occupied area – living room,
bedroom
• Device placed out-of-the-way
• Below 3rd floor – radon from the soil
• Why is it important?
• Radon gas is radioactive – α-particles
• Invisible and odourless
• Radon levels vary from place to place even for
two rooms that was separated only by a wall

18. HOW TO DETECT
RADON?
Radon Gas Measurement Methods
• By detecting the amount of the Radon gas
built-up
Radon Decay Measurement
• By looking at the source material and
measuring how much radioactive decay had
taken place.
The most accurate and reliable
Radon measurements are those
that continuously monitor Radon.
The test made sure to meet the EPA
requirements. The U.S. EPA and the
Centers for Disease Control and
Prevention recommend that
buildings with radon levels 4 pCi/L, or
greater, be fixed.

19. RADON GAS
MEASUREMENT METHODS
SHORT AND LONG-TERM TESTS, ACTIVE AND PASSIVE DEVICES, METHODS RESPECT TO DEVICES.

20. TIME/PERIOD
OF THE TEST
• Faster way to test
• Getting the initial Radon level: lowest level occupied, frequently
occupied space
• Test kits to remain in the building depends on the device (2 days – 90
days)
• Not a very accurate estimation of average radon level for the whole year
Short-term test
• Can be used to determine the initial short terms results (4 – 10)pCi/L
• More than 90 days
• The average radon level more likely to be accurate
• If the results is ≥4 pCi/L, EPA recommends the problem to be corrected.
Long-term test

21. TYPE OF DEVICES
Passive devices
• Do not need power to function
• Trap Radon or daughter products
• Analysed in the laboratory
• Examples:
• Alpha track detectors, charcoal
canisters, charcoal liquid
scintillation detectors
Active devices
• Requires power
• Include continuous monitoring
devices (Radon, working level)
• Detect and record Radon or its
daughter products continuously
• Generally, more costly
• Require professionally trained
testers for operating the devices

22. PASSIVE:
CHARCOAL
LIQUID
SCINTILLATION
• Typically used for short-term tests
1. Absorb radon or its products on to the
charcoal.
2. After an exposure period of 2 to 7 days, the
container with the charcoal returned to the
laboratory for analysis
3. Analysis is accomplished by treating the
charcoal with a scintillation fluid, then
analysing the fluid using a scintillation
counter.
4. The radon concentration of the sample site
is determined by converting from counts
per minute.

23. PASSIVE: FILTERED ALPHA
TRACK DETECTORS
1. The detector is a small piece of special plastic or film
inside a small container.
2. Air being tested diffuses through a filter covering a
hole in the container.
3. When alpha particles from radon and its decay
products strike the detector, they cause damage
tracks.
4. The container is sealed and returned to a laboratory
for reading. The plastic is chemically treated to make
the tracks visible, then the tracks are counted.
• Usually exposed from 3 to 12 months, but because they
are true integrating devices, alpha track detectors may be
exposed for shorter lengths of time when they are
measuring higher radon concentrations.

24. PASSIVE: ELECTRET ION
DETECTORS
• Usually only available through laboratories, long
(1 – 12 months), short (2 – 7 days)
1. Have a Teflon disc, which is an
electrostatically charged disk detector
(electret) is situated in ion chamber.
2. When an ion generated from radon decay
strikes the Teflon disc, the electrical charge is
reduced.
3. In the laboratory, the charge reduction is
measured and the radon level is calculated.

25. ACTIVE: GRAB RADON/ACTIVATED CHARCOAL
• Requires a skilled technician
1. Sampling radon by using a pump or a fan to
draw air through a cartridge filled with
activated charcoal and takes from 15
minutes to 1 hour.
2. After sampling, the cartridge is placed in a
sealed container and taken to a laboratory
where analysis is approximately the same as
for the activated charcoal or charcoal liquid
scintillation methods.

26. ACTIVE: GRAB
RADON/
SCINTILLATION
CELL
1. A skilled operator draws air through a filter
to remove radon decay products into a
scintillation cell.
2. To analyse the air sample, the window end
of the cell is placed on a photomultiplier
tube to count the scintillations (light pulses)
produced when alpha particles from radon
decay strike the zinc sulphide coating on
the inside of the cell.
3. A calculation is made to convert the counts
to radon concentrations. This test takes less
than an hour to complete.

27. ACTIVE: GRAB
RADON/PUMP-
COLLAPSIBLE
BAG
• Uses a sample bag made of material
impervious to radon.
1. Skilled technician using a portable
pump fills the bag with air at the sample
site.
2. Then, transports it to the laboratory for
analysis.
3. Usually, the analysis method is to
transfer air from the bag to a
scintillation cell and perform analysis in
the manner described for the grab
radon/scintillation cell.

28. OTHER METHODS
Three-Day
Integrating Evacuated
Scintillation Cell
Pump-Collapsible
Bag (1-day)
Charcoal canisters
Unfiltered alpha track
detector
Try to find out about these
methods.
Short-term? Long-term?
Active? Passive?

29. Thank You for attention!