Introduction to Ozone
Ozone is an elemental molecule with the formula O3, consisting of three oxygen atoms. It's an explosive, pale blue gas with a pleasant odor. Atmospheric ozone is found in two main layers of Earth's atmosphere. In the Earth's upper atmosphere, specifically in the stratosphere, ozone forms the protective ozone layer. This stratospheric ozone is produced by the action of solar ultraviolet radiation on atmospheric oxygen or molecular oxygen. At ground level, ozone is considered a pollutant and is often referred to as ground-level ozone.
Ground-level ozone is created through complex chemical reactions involving nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the presence of sunlight. These precursors can come from various sources, including power plants and vehicle emissions. Ozone formation is most likely to reach unhealthy levels on hot sunny days in urban environments, leading to peak concentrations in the afternoon and early evening.
O3 is an antimicrobial agent used in the production of bottled water, treatment of meat, and handling perishable foods. Ozone is created for commercial and industrial uses by exposing normal oxygen to a high voltage electrical discharge; or exposing oxygen to ultraviolet (UV) light.
Welders and others exposed to high ambient ozone concentrations can experience a number of health-related risks. Short-term symptoms range from irritated throat and chest, metal fume fever, and reduced lung function. Common long-term health effects are asthma, pneumonia, and even cancer. Ozone pollution can significantly affect human health, particularly impacting the respiratory tract. Both atmospheric ozone and ground-level ozone affect human health in different ways. While the ozone layer in the stratosphere protects us from harmful UV radiation, exposure to ground-level ozone can cause various health issues. The impact of ozone on human health is a growing concern, especially in urban areas with high NOx emissions and VOC levels, which contribute to ozone formation near the Earth's surface.
Gas Characteristics
- Colorless to bluish gas that condenses to a dark blue liquid, or blue-black crystals
- Has a pungent odor
- An oxidizing agent
- Very high redox potential
- Nonflammable gas
- O3 will quickly corrode most metals and will damage most plastics.
- Rubber exposed to ozone will quickly harden and crack.
- Manufactured for immediate use because of its instability and tendency to decompose quickly
- Pure ozone gas is slightly heavier than air
- OTHER NAMES: Triatomic oxygen, trioxygen
- CAS Registry 10028-15-6
FIRST AID
- The lungs will usually recover within a few days after exposure to elevated concentrations of ozone. However, if ozone exposure is experienced over a longer period of time or on a number of repeated occasions within a year, chronic damage to lung tissue may occur.
- O3 is highly toxic if inhaled or by contact of liquid to skin, eyes, or mucous membranes. It can cause acute to chronic lung damage, burns, permanent injury, or death.
- Ozone can be toxic at a concentration of 100 ppm for 1 minute. It's capable of causing death from pulmonary edema.
- Evaluation of ozone toxicity is similar to the evaluation of any pulmonary irritant. Oxygen saturation monitoring should be implemented and also bedside spirometry.
- No specific treatment is available for individuals exposed to ozone, though some have suggested that oral intake of Vitamin E is beneficial to the chronic ambient exposure most experience.
IF ACCIDENTALLY RELEASED
- Take action only if you've been trained. Evacuate the surrounding area. Turn off all possible sources of ignition. Don't inhale gas and ensure the area is well ventilated. Wear a respirator if ventilation isn't adequate. Workers should be wearing personal protective equipment.
- In case of a spill: Immediately contact emergency personnel. Stop leak if there isn't a risk to yourself. Use spark-proof tools and explosion-proof equipment.