Building Occupant and Worker Exposures to Elevated Levels of Nitrogen Dioxide in Puerto Rico

Nitrogen dioxide, along with nitric oxide, are the two most prevalent oxides of nitrogen according to the U.S. Environmental Protection Agency (EPA). Both are toxic gases with nitrogen dioxide being a highly reactive oxidant and corrosive. Nitrogen dioxide is also one of the indoor pollutants frequently listed by health authorities as a possible exposure concern in the built environment.

Potential health effects associated with exposure to elevated levels of nitrogen dioxide listed by EPA include:

• NO₂ acts mainly as an irritant affecting the mucosa of the eyes, nose, throat and respiratory tract
• Extremely high-dose exposure (as in a building fire) may result in pulmonary edema and diffuse lung injury
• Continued exposure to high levels can contribute to the development of acute or chronic bronchitis
• Low level exposure may cause increased bronchial reactivity in some asthmatics, decreased lung function in patients with chronic obstructive pulmonary disease, and an increased risk of respiratory infections - especially in young children

Nitrogen dioxide primarily gets in the air from the burning of fuel. It forms from emissions from vehicles, power plants and off-road equipment. Indoors, the primary sources listed by EPA also come from combustion processes. They include:

• Unvented combustion appliances, such as gas stoves
• Vented appliances with defective installations
• Welding
• Tobacco smoke
• Kerosene heaters

“EPA warns that in homes with gas stoves or other combustion devices, indoor levels of nitrogen dioxide often exceed outdoor levels,” said Harry Pena, President of Zimmetry Environmental. “There are also a number of occupations where workers could be exposed to elevated concentrations of it. This is why the Occupational Safety and Health Administration (OSHA) has set a Permissible Exposure Limit-Ceiling (PEL-C) and the National Institute for Occupational Safety and Health (NIOSH) has a Recommended Exposure Limit-Short Term Exposure Limit (REL-STEL) for nitrogen dioxide.”

To protect building occupants and workers in Puerto Rico and across the region, and to help businesses comply with health and safety regulations, the IAQ and industrial hygiene professionals at Zimmetry offer testing, monitoring, training and consulting services. Their experts identify and mitigate exposure risks to nitrogen dioxide and many other health and safety hazards. They even recently sponsored an educational video about nitrogen dioxide and the indoor environment that can be seen at: https://youtu.be/4i6ng9kuLkM

To learn more about Zimmetry’s industrial hygiene, indoor air quality, environmental, compliance and consulting services, please visit www.zimmetry.com, call (787) 995.0005 or email info@zimmetry.com .

About Zimmetry Environmental
Since 2002, Zimmetry Environmental has been providing environmental consulting services to building owners and managers, architects, engineers, EHS professionals and Fortune 500 companies. The company is based in Puerto Rico and provides services across the Caribbean and Central America. The professionals at Zimmetry offer environmental compliance, indoor air quality, asbestos, lead-based paint, Phase I ESAs and general environmental consulting services.

Contact Information

Paul Cochrane

President

Cochrane & Associates, LLC

Contact via E-mail