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Fiberglass Exposure



The heating/air conditioning system in our house has some fiberglass insulation in the return. The return uses the stud wells in the house to get the air back to the heater/AC. The piece of insulation is about 12 inches by 12 inches and is covering a water pipe also in that part of the wall. I noticed this a couple of weeks ago, but it is in a spot where I cannot reach it to remove. I also can tell that the air is going through it as it moves when the system is on. I was just wondering if this was constantly putting fiberglass fibers into the air in my home, and my family is breathing it? I notice in spots were dust has collected in the house that there is a sparkly particle in it. I`ve been told this could be fiberglass fibers. I`m just really concerned for my family`s safety in breathing the air. I have been having a lot of anxiety about this for the last few weeks.


I can't be of too much help here because I don't know much about HVAC systems. However, it is possible that some fibers are being released into the return. Does the return air flow through a filter before it goes back into the system for heating/cooling? Keeping that filter clean through regular changing will improve the air quality in general and will help capture any fiberglass. The long term health risks associated with fiberglass are sketchy, but I have pasted a 2001 statement from the International Agency for Research on Cancer (IARC) that indicates that fiberglass insulation is not considered a human carcinogen.

IARC 2001: The IARC working group revised their previous classification of glass wool being a possible carcinogen. It is currently considered not classifiable as a human carcinogen. Studies done in the past 15 years since the previous report was released, do not provide enough evidence to link this material to any cancer risk.

If you are worried about the insulation and cannot remove it yourself, I would suggest hiring an HVAC contractor to come out and work on the system. Remember, the insulation may be there for a good reason so you want to make sure removing it is OK.

Related Resources:

Health and Safety Facts for Fiber Glass

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Response by:

J Mac Crawford, PhD, RN J Mac Crawford, PhD, RN
Clinical Associate Professor of Environmental Health Sciences
College of Public Health
The Ohio State University