Nitrogen gas and oxygen safety: A guide to risks and precautions

Nitrogen and oxygen play a vital role in many industrial and commercial applications, but their safe handling is critical. Although nitrogen is non-toxic and non-flammable, it can displace oxygen in confined spaces, creating a risk of asphyxiation. Oxygen, while essential for life, can increase the risk of fire and explosions when present in high concentrations.

To maintain a safe working environment, it is essential to understand how these gases behave and apply proper safety measures. This includes ensuring adequate ventilation, using gas monitoring systems, storing gases correctly, and providing staff training.

In particular, enriched oxygen environments can intensify flammability hazards, making it important to follow recognised standards such as ISO 14520 for gaseous fire-extinguishing systems. By addressing these safety considerations proactively, businesses can minimise risks, protect workers, and ensure safe and continuous operations.

In environments where flammable materials are present, understanding the properties of nitrogen and oxygen is essential for maintaining safety.

Nitrogen is an inert, non-flammable gas commonly used to reduce oxygen levels and create safer conditions. Although it doesn’t burn or support combustion, excessive nitrogen in enclosed spaces can lead to potential suffocation risks. 

• Explore nitrogen in fire suppression and prevention

Conversely, oxygen supports combustion and, when enriched, can dramatically increase the flammability of materials, making even typically non-combustible substances ignite more easily. Effective gas safety protocols must consider these properties to prevent ignition risks and ensure a controlled atmosphere in sensitive applications.

While nitrogen is a non-flammable gas, improper handling can pose serious safety risks, especially in confined or enclosed environments like archives, laboratories, or industrial facilities.

Key hazards include:

• Oxygen displacement and asphyxiation: When nitrogen gas is released into the air, it can displace oxygen, leading to dangerously low oxygen levels. This may result in asphyxiation, which can be fatal if not addressed promptly.
• Explosion risk in confined spaces: In areas with poor ventilation or improper gas level management, imbalanced concentrations of nitrogen and oxygen can create hazardous conditions, including an increased risk of explosions.
• Oxygen-enriched environments: Elevated oxygen levels can significantly increase the flammability of materials such as clothing, creating a heightened risk of fire accidents.

To reduce these risks, it’s important to follow strict safety protocols, ensure proper ventilation, and regularly monitor gas levels in the working environment.

Bottled gases are commonly used by small consumers for various applications, ranging from industrial processes to medical uses. These gases are stored in high-pressure bottles, typically at 150 Bar or 300 Bar, and are supplied by trucks, requiring extensive handling to transport them to the location of use.  

Handling during transportation

The process of carefully loading, transporting and unloading the large, heavy bottles safely is time-consuming and labor-intensive, leading to increased operational costs and potential delays.  

Risk of accidents  

High-pressure gas bottles pose significant safety risks that necessitate rigorous handling protocols and safety measures to prevent accidents. A significant leakage or sudden release of high-pressure gas can turn the bottle into a projectile, posing a danger to personnel and property.

Alternatives such as integrated gas supply systems or low-pressure storage options can minimize these risks, ensuring a safer environment for workers and reducing the likelihood of accidents. Besides enhanced safety, alternatives also offer benefits such as improved efficiency, cost savings, and environmental advantages.

Liquid gases are used for large consumers. The nitrogen and oxygen are liquified to make large volumes of nitrogen very compact for transport. Liquid nitrogen is supplied by trucks to a liquid tank at the customer site, where it is evaporated to gaseous form again. Liquid gases poses several risks due to their extremely low temperature of -183°C (-297°F) for nitrogen or -218.79°C (-361.82°F) for oxygen

• Cryogenic burns: Direct contact with liquid nitrogen can cause severe frostbite or cryogenic burns.
• Asphyxiation: Liquid nitrogen can displace oxygen in the air, leading to a risk of asphyxiation in confined spaces.
• Pressure hazards: When going from liquid to gaseqous form, the gas expands 700-800 times.Rapid expansion of this liquid to gas can cause pressure build-up, potentially leading to explosions if not properly vented.
• Material embrittlement: Prolonged exposure to liquid nitrogen can make materials brittle and prone to cracking.

Of the three options, onsite generation has the least risk since only the volume of nitrogen or oxygen required is produced on the spot at the pressure required by the applications. This drastically reduces the risks caused by high-pressure bottles or the low temperature of liquefied gases.

To prevent accidents and ensure a safe working environment, it is essential to follow proper safety precautions for nitrogen and oxygen handling to prevent nitrogen suffocation and oxidizing hazards.

The following safety precautions must be taken:

• Ventilation: Use ventilation when handling liquid nitrogen or working with nitrogen gas in environments such as museums or libraries that contain flammable materials. This will help to prevent the buildup of nitrogen in the air and reduce the risk of asphyxiation.
• Personal protective equipment (PPE): Wear appropriate PPE, including insulated gloves, safety glasses, and face shields. This will help to protect against rapid freezing of skin and eye tissue.
• Proper storage and handling: Store liquid nitrogen only in approved containers designed for cryogenic liquids. Never seal liquid nitrogen in a tightly closed container due to pressure buildup.
• Equipment Safety: Use equipment rated for the appropriate cylinder pressure when handling compressed nitrogen. Protect cylinders from physical damage and secure them properly.

Environmental monitoring and warning systems are crucial not only for detecting changes in oxygen levels but also for identifying potential explosion risks in vulnerable spaces like galleries.

Here are some tips for environmental monitoring and warning systems:

• Use oxygen monitors and alarms in areas where nitrogen is used or stored.
• Implement warning systems and continuous atmospheric monitoring in enclosed spaces.

Training and personnel preparation are crucial for ensuring a safe working environment. To foster proper nitrogen and oxygen gas safety, particularly in cultural spaces.

It is recommended to:

• Train personnel on the hazards of nitrogen asphyxiation and proper handling procedures.
• Provide ongoing education and awareness on the risks associated with nitrogen gas handling, including concerns about nitrogen gas leaks, nitrogen toxicity, and nitrogen explosions. and the importance of safety protocols.

Ensuring nitrogen and oxygen safety is crucial for preventing accidents, especially those associated with nitrogen gas and oxygen, and ensuring a safe working environment. By understanding the properties and risks associated with these gases, following proper safety protocols, and implementing environmental monitoring and warning systems, we can reduce the risk of accidents and ensure a safe working environment. Remember, nitrogen and oxygen safety is everyone's responsibility, and by working together, we can create a safer workplace.