RMS Radon Science & Health Effects 5

Question 1

What is the approximate indoor radon concentration at which the EPA estimates a lifetime lung cancer risk of about 1 in 100 for non-smokers?

Accepted Answer

4 pCi/L

Answer

At 4 pCi/L, EPA estimates approximately 7 lung cancer deaths per 1,000 non-smokers and about 62 per 1,000 smokers over a lifetime.

Question 2

Why is radon considered a 'noble gas' with respect to its chemical behavior in the body?

Accepted Answer

It is chemically inert and does not react with lung tissue itself — only its progeny do

Answer

Radon itself is a noble gas and chemically unreactive; the health hazard comes from its radioactive progeny that deposit and emit alpha particles in lung tissue.

Question 3

Lung cancers attributed to radon exposure most commonly originate in which histological cell type?

Accepted Answer

Small cell and squamous cell carcinoma

Answer

Miner studies show radon preferentially causes small cell and squamous cell carcinomas arising from central bronchial epithelium where progeny deposit.

Question 4

The 'unattached fraction' of radon progeny refers to progeny that:

Accepted Answer

Are not attached to aerosol particles and deposit more efficiently in the airways

Answer

Unattached progeny are submicron clusters that deposit highly efficiently in the upper airways, delivering a greater dose per unit concentration than attached progeny.

Question 5

Which statement about radon in well water is accurate?

Accepted Answer

Radon can be released from water during use (showering, dishwashing) and contribute to indoor air radon

Answer

When radon-bearing water is agitated during household use, radon off-gasses into indoor air, typically contributing about 1/10,000 of the water concentration to indoor air levels.

(RMS) Radon Mitigation Specialist Practice Test

(RMS) Radon Mitigation Specialist Practice Test

RMS Radon Science & Health Effects 5