2026 SOLVED QUESTIONS GRADED A+
◉ The four Soil Suction Mitigation techniques. Answer: Subslab
suction,
drain-tile suction,
sump-hole suction,
or block-wall suction
◉ What is an Alpha Particle. Answer: Two neutrons and two protons
bound as a single particle emitted from the nucleus of certain radioactive
isotopes in the process of decay.
◉ Closed House Procedures. Answer: During any short-term test,
closed-house conditions should be maintained as much as possible while
the test is in progress. In tests lasting fewer than four days, closed-house
conditions should be maintained for at least twelve hours before starting
the test, as well as for the duration of the test. While closed-house
conditions are not required before starting tests lasting between four and
ninety days, they should be maintained as much as possible.
, ◉ Curie. Answer: a standard measurement for radioactivity, specifically,
the rate of decay for a gram of radium at 37 billion decays per second; a
unit of radioactivity equal to 3.7 x 1010 disintegrations per second.
◉ Equilibrium Ration. Answer: At complete equilibrium (i.e., at an
equilibrium ratio of 1), 1 WL of RDPs would be present at the radon
concentration of 100 pCi/L. The ratio is never 1 in a house; due to
ventilation and plate-out, the RDPs never reach equilibrium in a
residential environment. A commonly assumed equilibrium ratio is 0.5
(i.e., the decay products are halfway toward equilibrium), in which case
1 WL would correspond to 200 pCi/L. However, equilibrium ratios vary
with time and location, and ratios of 0.3 to 0.7 are commonly observed.
◉ Picocurie (pCi):. Answer: one pCi is one-trillionth of a curie, 0.037
disintegrations per second, or 2.22 disintegrations per minute.
◉ Picocurie per liter (pCi/L):. Answer: a unit of radioactivity
corresponding to an average of one decay every 27 seconds in a volume
of 1 liter, or 0.037 decays per second per liter of air or water. 1 pCi/L =
37 becquerels per cubic meter (Bq/m3).
◉ Quality Assurance (QA). Answer: a complete program designed to
produce results that are valid, scientifically defensible, and of known
precision, bias, and accuracy; includes planning, documentation, and
quality-control activities.