Nitrogen is widely used in the food industry for extending shelf life for extending shelf life, improving product quality, and creating inert environments. Although nitrogen itself is not toxic, its use brings specific safety risks. The main hazards are oxygen displacement (risk of suffocation), risks associated with using liquid nitrogen such as freezing, and pressure-related dangers during storage and transport. For safe use, adequate ventilation systems, oxygen monitoring, personal protective equipment, and thorough staff training are essential.
Why is nitrogen used in the food industry?
Nitrogen is used in the food industry due to its unique properties that help maintain the quality and freshness of food products. As an inert gas, nitrogen is non-reactive with food, making it ideal for applications where oxidation must be prevented.
The most common application is in Modified Atmosphere Packaging (MAP), also known as gas packaging. This technique replaces the air in packaging with a controlled gas mixture containing nitrogen. This inhibits bacterial growth, prevents oxidation, and significantly extends the shelf life of products such as meat, fish, cheese, vegetables, and fruit.
Additionally, nitrogen is used to remove oxygen from production areas, for cooling and freezing foods (in liquid form), and for creating inert environments in storage tanks. In the beverage industry, nitrogen is employed to transfer liquids and pressurize tanks without risk of oxidation.
Despite these advantages, safety remains a crucial consideration. The properties that make nitrogen useful – such as its ability to displace oxygen – simultaneously represent the greatest risk factors when used carelessly.
What are the main safety risks of nitrogen use?
The primary safety risks associated with using nitrogen in the food industry relate to the physical properties of this gas. The greatest danger is oxygen displacement, which can lead to suffocation hazards in confined spaces.
Nitrogen is odorless, colorless, and tasteless, meaning workers may not be aware of exposure until symptoms of oxygen deficiency occur. At high nitrogen concentrations, the oxygen content in the air decreases, which can lead to unconsciousness and even death without prior warning signals. Areas with nitrogen installations, such as storage facilities or production areas, are high-risk locations.
When using liquid nitrogen (temperature approximately -196°C), there is a risk of frostbite and tissue damage from direct skin contact. Even brief contact can cause severe freezing injuries comparable to burns.
Pressure-related risks occur during the storage and transport of nitrogen under pressure. Faulty equipment, overpressure, or damaged pressure vessels can lead to explosion hazards or the uncontrolled release of large quantities of gas.
Beyond these physical risks, there is also the danger of insufficient knowledge and training among employees. Improper handling, lack of awareness of the hazards, and failure to follow safety protocols significantly increase the likelihood of incidents.
How can you recognize and prevent oxygen displacement by nitrogen?
Oxygen displacement is the greatest safety risk when working with nitrogen and requires special attention. Normal air contains approximately 21% oxygen, but when this percentage drops below 19.5% due to nitrogen accumulation, an oxygen-deficient environment can develop that may be life-threatening.
The symptoms of exposure to an oxygen-deficient environment often develop rapidly and can begin with mild headaches, dizziness, and fatigue. With continued exposure, coordination problems, impaired judgment, confusion, nausea, and vomiting may occur. Eventually, this can lead to unconsciousness and death without victims having the opportunity to call for help.
To prevent oxygen displacement, several measures are essential:
- Install permanent oxygen detection systems in areas where nitrogen is used or stored
- Ensure good ventilation, preferably with mechanical air exchange
- Use personal oxygen monitors for employees working in risk areas
- Implement strict access control for confined spaces where nitrogen may be present
- Ensure alarm systems are clearly audible and visible and activate automatically at low oxygen levels
For effective prevention, it is crucial that employees are trained to recognize the symptoms of oxygen deficiency in themselves and others, and that they know how to respond in emergency situations. A “buddy system” where employees never work alone in areas with nitrogen installations is an important safety measure.
What safety measures are mandatory when using nitrogen?
When using nitrogen in the food industry, various safety measures are legally required to manage the risks. These measures are established in occupational health and safety legislation and industry-specific standards and guidelines.
Companies must conduct a comprehensive risk assessment and evaluation for activities involving nitrogen. This document identifies specific hazards and defines preventive measures. Oxygen detection systems are mandatory for spaces with nitrogen installations and must be linked to automatic alarm systems that warn when oxygen levels fall below 19.5%.
Personal protective equipment (PPE) is essential, especially when working with liquid nitrogen. These include:
- Cryogenic gloves that provide protection against extreme cold
- Face protection or safety glasses with side protection
- Special protective clothing that covers the entire body
- Personal oxygen detectors for employees in risk areas
Safety protocols and work procedures must be documented in writing and regularly updated. These include emergency procedures, evacuation plans, and specific work instructions for handling nitrogen. All employees who work with nitrogen must undergo mandatory safety training and receive regular refresher courses.
For confined spaces where nitrogen may be present, additional strict access protocols apply, including work permits, atmosphere measurements before entry, and continuous monitoring during activities.
How do you ensure safe storage and transport of nitrogen?
Safe storage and transport of nitrogen require specific measures, depending on the form in which the nitrogen is held. Stricter regulations apply to liquid nitrogen and nitrogen under pressure than to nitrogen generators that produce the gas on-site.
Nitrogen cylinders and pressure vessels must be stored in well-ventilated areas, away from heat sources, direct sunlight, and flammable materials. Storage areas must be equipped with clear warning signs and access restrictions for unauthorized personnel. Cylinders should always be stored upright and secured to prevent falling.
When transporting nitrogen cylinders within the company, special transport carts must be used to secure the cylinders against falling or impact. During road transport, ADR regulations (European regulations for the transport of dangerous goods) apply, including specific labeling and documentation.
For installations with liquid nitrogen, additional safety measures are necessary:
- Cryogenic tanks must comply with the PED (Pressure Equipment Directive)
- Pressure relief devices must be present to regulate pressure increases
- Sufficient space must be available around tanks for safe operation and maintenance
- The insulation of pipes and equipment must be checked regularly
When installing nitrogen generators that produce nitrogen on-site, you must ensure adequate space, ventilation, and technical provisions according to the manufacturer’s specifications. Regular maintenance and inspection of all nitrogen equipment by qualified personnel is essential for safe operation.
What should you remember about working safely with nitrogen?
Working safely with nitrogen in the food industry requires a systematic approach that combines awareness, training, and technical measures. Understanding and respecting the inherent risks of nitrogen is the foundation for a safe working environment.
Always keep these core principles in mind:
- Nitrogen itself is not toxic, but it can displace oxygen, leading to suffocation hazards
- Technical provisions such as good ventilation and oxygen detection are essential
- Employees must be thoroughly trained and aware of the risks
- Personal protective equipment is necessary, especially with liquid nitrogen
- Emergency procedures must be known and regularly practiced
Investing in safety is not only a legal obligation but also contributes to more efficient business processes and continuity. By integrating safety measures into daily work routines, you create a culture where working safely with nitrogen becomes second nature.
For optimal safety with industrial nitrogen systems, at Presscon we work with our customers to develop solutions that not only meet all safety standards but also align with the specific needs of your food production processes. Our years of experience across various industries enable us to advise you on the safest and most efficient implementation of nitrogen technology in your business. Contact our nitrogen safety specialists today.