Instructions for Making a Screening-Type
Measurement with a Radon Detector
PLEASE READ
Before you begin
To
obtain a valid screening measurement, the following conditions should exist for
12 hours prior to and during the sampling period.
* All windows and external doors should
be closed, except for normal entering and exiting.
* Fans
and ventilation systems that use outside air, such as attic fans and bathroom
fans, should not
be operated during the sampling period. Air conditioners can be used.
Instructions for Sampling Location and
Conditions
* Do not open the canister to begin the
measurement if you cannot close it within the specified time period or if you
are installing a new
heating
or air conditioning system.
* Do not start test if weather
predictions indicate a severe storm with wind speeds of 30 mph or greater is
expected within the testing period.
* If a time error is made or you decide
not to use the canister, please return using the prepaid mailer. PLEASE DO NOT DISCARD.
* Measurements should be made in the
lowest lived in area in the house i.e.,basement,
bedroom or a playroom. Non-suitable areas are
bathrooms,
kitchens, laundry rooms, root cellars, garages, crawl spaces or sumps.
* The canister should not be placed in a
location exposed to noticeable drafts or areas where the canister can get hot.
The canister should
be
exposed to the air people breathe. It should be placed at least 20 inches above
the floor and 3 feet from an outside wall, not in a closet,
drawer,
or cupboard.
Purpose of a Screening-type Measurement
The
purpose of a screening-type measurement is to quickly determine if a house
contains high concentrations of radon gas; to provide information
for
deciding the need for additional measurements.
The following sampling instructions reflect the EPA recommended
measurement procedures
for this
method. The procedures are based on the
assumption that the greatest source of radon is the soil underlying the
house. If other sources
are
suspected, additional measurements in different locations in the home may be
considered.
SAMPLING INSTRUCTIONS
Your radondetek test kit should contain one tape-sealed canister
and a box or padded envelope. If anything is missing, or if the canister has
been damaged in shipping, call us at
1. REMOVE the canister
from the box or envelope. SAVE THE
2. RECORD INFORMATION ON LABEL ON BOTTOM OF CANISTER. Fill in name, address, exact starting date and time, and location placed.
3. OPEN THE CANISTER. Remove the tape from around the canister. Wrap the tape around the lower half of the canister. Remove the lid and place
it under the canister.
4. PLACE THE CANISTER. Put the canister, open side up, on a table or shelf according to the sampling location instructions. (See above)
5. WAIT. Do not move the canister after the test has started. If the canister has black tape, the canister should remain open for 2 days (48 hours).
If the canister has red or blue tape, it should remain open for 3-5 days (72-96 hours) The closing time can vary from 2 hours earlier to 2 hours later
than the time opened. ie;
if opened
6. REPLACE TOP
cover the label.
7. RECORD THE EXACT STOP DATE
8. PLACE CANISTER IN THE
9. MAIL within one day of resealing. Send first class mail.
YOUR SAMPLE WILL BE
ANALYZED THE DAY IT ARRIVES AT OUR
REPORT WILL BE E-MAILED OR FAXED THAT DAY OR MAILED THE NEXT BUSINESS DAY.
IF YOU DO NOT RECEIVE YOUR REPORT WITHIN 10 DAYS, PLEASE CONTACT US.
Activated Charcoal Adsorption Detector Operation
The device consists of a covered metal canister filled
with activated charcoal that is held in place by a metal wire mesh, and a metal
ring or
glue. This is a passive device that, when uncovered, allows the radon to move
through the charcoal by diffusion; therefore,
no external source of power is needed. The radon gas will
attach to the charcoal surfaces. The canister is sealed at the end of the
exposure
period, trapping the accumulated radon gas. A minimum delay of four hours is
required before the canister can be
counted.
For counting, the sealed canister is placed in a sodium iodide crystal counting
system for at least ten minutes. During
this time,
the gamma rays emitted are counted. After analysis, the counts are converted
into radon gas units of picocuries per
liter
(pCi/L) of air using a calibration factor determined by the exposure
conditions.