Q & A

What is radon?

Radon is a naturally occurring radioactive gas that comes from the natural breakdown of uranium in soil, rocks, and water.  Levels of radon are common in the air we breathe every day, and radon sometimes penetrates buildings through their foundations. 

Why is the College testing for radon?

Though radon is common in the everyday living environment, the US Environmental Protection Agency has set guidelines that recommend limiting residential levels to 4 picoCuries/liter (pCi/L) because of health risks associated with long-term exposure to high radon levels.  Gettysburg sits on a geologic formation known as the Reading Prong that has an elevated uranium content.  The College will maintain a schedule of radon assessment to ensure the College buildings remain within EPA guidelines.

What factors influence radon levels in a building?

A large number of factors influence indoor radon concentrations:

• The amount of uranium in the geological structures underlying the soil and how close the underlying structures are to the soil surface;
• The concentration of radon in the soil and the permeability of the soil;
• Time of day (radon concentrations often reach a peak in the middle of the night because of temperature differences between inside and outside spaces) and the season;
• Weather conditions, such as temperature, wind speed and direction, and humidity;
• Building structure (slab construction, presence of crawl spaces);
• Ventilation conditions (areas where doors and windows may not be opened regularly);
• Type, operation, and maintenance of the heating, ventilation, and air conditioning (HVAC) system

How does the College test for radon?

The EPA guidelines for Radon Measurement in Schools are used as the basis for testing at Gettysburg College.   There are a variety of tests available to measure the level of radon present, and there are advantages and disadvantages to each type of test.   One of the most widely available is a short-term test that utilizes charcoal canisters.   Charcoal canisters are typically placed for 3-5 days and then collected and analyzed.  Charcoal testing is good for quick assessments of the radon present during the time the canisters were present, but it only presents a "snapshot" of the conditions during those 3-5 days.  If radon levels were higher than usual because of weather conditions or because the building was more tightly closed than usual (closed windows and doors providing less ventilation, for example), then a false positive might be indicated.  It is also possible for charcoal testing to indicate measured radon levels that are lower than average.  The most reliable testing is long-term testing which involves the use of detectors for 90 days or longer.   Long term testing allows the effects of weather conditions and building ventilation to achieve more balance, and a better picture of the occupants' long term exposure to radon.   The Environmental Protection Agency's  guidelines for Radon Measurements in Schools includes a combination of short- and long-term testing designed to achieve a balance between obtaining the most accurate test results and mitigating as quickly as possible. 

What does the sampling canister look like?

The sampling canisters are small metal canisters, with a metal screen covering activated charcoal.  The canister is about 2-3" in diameter and has a strip of tape around its edge used to seal the canister lid before and after testing to keep it airtight.

Do the air sampling canisters pose any health risk?

No.  The charcoal which the canisters contain is not hazardous, and the charcoal does not re-emit the radon after the radon is adsorbed.

Where can I expect to see the sampling canisters?

A sampling canister will be placed in rooms, occupied for more than 2 hours per week that are in contact with the ground or are above closed crawl spaces.

Why is testing only being performed at the lower levels of a building?

EPA studies indicate that radon levels on upper floors are not likely to exceed the levels found in ground contact rooms.  Testing rooms in contact with the ground is sufficient to determine if radon is a problem in a building.

Why isn't the College testing every space that could potentially be occupied?

The risk of adverse long-term effects is proportional to the amount of time spent in an area.  This means that, if only a short time is spent in an area which has a significantly elevated radon level, the total exposure is not likely to exceed the risk of spending a long time in an area with an only slightly elevated level.  In designing its protocol for sampling in schools, the EPA recognized that measurement and mitigation resources should be concentrated on areas in which occupancy is at least 2 hour per week or more.

If there are elevated radon levels in the room next to mine, does that mean there will be elevated levels in my room?

Not necessarily.  Indoor radon levels vary from room to room, depending on:  the pattern of airflow in the building; the location of features such as crawlspaces and foundation cracks; and the depth of soil and rock under different parts of the building.  Therefore, it is not possible to make a reliable prediction.  The only way to determine radon levels throughout a building is to test in all frequently occupied areas.

If there are elevated radon levels in the building next to mine, does that mean there will be elevated levels in my building?

Not necessarily.  Indoor radon levels vary from building to building, so it is not possible to make a reliable prediction.  Do not rely on radon test results taken in other buildings nearby to estimate the radon level in your building.  The only way to determine radon levels in a given building is to test.

Does the age of my building affect radon levels in the building?

The age of a building does not necessarily affect radon levels in a building.  Although an older building is more likely to have crawl spaces exposed to the soil or cracks in the foundation that could allow the infiltration of radon into the building, some old buildings are less air-tight, which could prevent the build-up of radon.  Additionally, if the geological make-up of the rock under the building doesn't contain much uranium, there is no reason to expect elevated radon levels in the building regardless of age.

What is a picocurie?

The quantity of radioactivity present is expressed in a unit called the Curie.  One Curie is equivalent to 37 billion radioactive atoms disintegrating per second.  However, the amount of radioactive atoms disintegrating per second as a result of the presence of radon in air is only a very small fraction of a Curie.  In fact, the most convenient unit to express the amount of radioactivity present in air is the picoCurie, which is 1 trillionth of a Curie.  For example, if a building has a radon level of 1 pCi/L of air this is equivalent to 0.037 radioactive atoms disintegrating per second in that liter of air.

Does radon cause headaches, eye irritation, or sick-building syndrome?

No.

Is radon in water a problem?

The primary entry route of radon in schools is through the soil.  However, radon can also enter through the water supply.  It can then be released into the air while using water.   Radon in water is not a problem for public water supplies which must be tested per EPA requirements.  Gettysburg College water comes only from public water supply.

Are building materials likely to contain or emit radon?

Radon emission from soil gas and its subsequent entry through the building foundation is the major source of radon contamination in schools.  Some building products such as phosphogypsum wall board, cinder block, and concrete may emit radon, but EPA studies indicate these concentrations are likely to be insignificant.

What resources are available for additional information?

                A Citizen's Guide to Radon (EPA)

If my question is not answered here, who can I contact at the College?

Questions should be directed to Regina Campo, Co-director of Human Resources and Risk Management at 717-337-6202.