Understanding Portable Oxygen on Commercial Flights
The question of whether portable oxygen cans are allowed on flights is critical for passengers relying on supplemental oxygen. While personal oxygen concentrators (POCs) are often permitted, the term 'oxygen cans' typically refers to compressed oxygen cylinders, which are generally prohibited due to safety regulations. Airlines and aviation authorities classify these pressurized containers as hazardous materials, posing a fire risk if damaged or mishandled during flight. This strict stance aims to ensure the safety of all passengers and crew by preventing potential inflight emergencies.
- Compressed oxygen cylinders are usually prohibited on flights.
- Personal Oxygen Concentrators (POCs) may be permitted with airline approval.
- Always verify specific airline policies before travel.
- Notify the airline in advance of travel needs.
Many travelers confuse portable oxygen cans with Personal Oxygen Concentrators (POCs). POCs are electronic devices that extract oxygen from the ambient air, whereas 'oxygen cans' or cylinders contain a finite supply of pure, compressed oxygen. This fundamental difference is why regulations treat them so differently. Understanding this distinction is the first step in ensuring compliance and avoiding disruptions to your travel plans. The International Air Transport Association (IATA) and the U.S. Department of Transportation (DOT) provide frameworks that most airlines follow, but individual carrier policies can vary.
For passengers who require oxygen therapy, planning ahead is paramount. The primary challenge lies in the pressurized nature of the cylinders. Unlike a standard carry-on item, a pressurized container can be extremely hazardous under the fluctuating cabin pressures and potential for impact during transit. Therefore, the default answer is that you cannot bring standard oxygen cans onto a commercial aircraft. This policy is not arbitrary; it is rooted in decades of aviation safety research and protocols designed to mitigate risks associated with volatile substances.
The Critical Difference: Cylinders vs. Concentrators
The core of the confusion stems from the terminology and the physical form of oxygen delivery devices. Portable oxygen cylinders, often referred to as 'oxygen cans,' are metal containers holding oxygen under high pressure. When opened, this oxygen is released, providing a direct supplement. Because they are pressurized vessels, they fall under stringent regulations governing compressed gases, similar to aerosols or other pressurized items that are restricted or banned from aircraft cabins. Their potential for rupture or leakage in the event of an accident or pressure changes makes them a significant safety concern for airlines.
In contrast, Personal Oxygen Concentrators (POCs) are battery-operated or plug-in devices that function by filtering nitrogen from the air, delivering a higher concentration of oxygen to the user. They do not contain pressurized oxygen and are therefore viewed as medical devices rather than hazardous materials. While POCs are generally allowed, airlines typically require advance notification and may have specific rules regarding battery types, quantities, and charging capabilities. This distinction is vital for anyone planning to travel with an oxygen supply.
A common misconception is that any portable oxygen device is automatically allowed. However, the distinction between a pressurized cylinder and an air-separating concentrator is the deciding factor for airline approval. Passengers must be clear about the type of device they intend to bring and research the specific policies related to that device type. Relying on generic information can lead to unexpected issues at the airport, potentially preventing you from boarding.
Navigating Airline Policies for Oxygen Devices
When considering travel with oxygen, the most crucial action is to consult directly with your chosen airline. Each carrier operates under federal regulations but implements its own specific policies regarding the carriage of medical equipment, including oxygen devices. These policies can differ in terms of notification periods, documentation requirements, and the types of devices permitted. What might be acceptable on one airline could be grounds for refusal on another, making direct verification indispensable.
Airlines typically require passengers to inform them of their need for supplemental oxygen at least 48 hours in advance of their flight. This notification allows the airline to make necessary arrangements and review your specific situation. You may be asked to provide a doctor's note or a medical certificate confirming that you are fit to fly and specifying the type of oxygen device you will be using. This documentation helps the airline assess the situation and ensure that all safety protocols are met without compromising your health.
Required Documentation and Advance Notice
The documentation requirements are a critical part of the process. Airlines need assurance that your medical condition and the device you plan to use are safe for air travel. A physician's statement typically needs to confirm:
- Your ability to manage your oxygen device independently.
- That the device is in good working order.
- The prescribed oxygen flow rate.
- The maximum flight duration and the amount of oxygen required for the trip, including layovers.
This information helps the airline determine if they can accommodate your needs and what, if any, additional support might be necessary. For example, some airlines might need to confirm that your device's batteries will last for the entire duration of the flight, including potential delays. Not providing this documentation or failing to give sufficient advance notice can lead to your request being denied, even if the device itself would otherwise be permissible.
The advance notice period is not merely a formality; it’s a safety and logistical requirement. It gives airline staff time to properly assess your medical needs, confirm device compatibility, and ensure that no onboard equipment conflicts arise. For instance, some aircraft may have limitations on the number of POCs that can be operated simultaneously due to electrical load considerations. Early notification helps manage these potential issues proactively.
Carry-on vs. Checked Baggage Restrictions
Oxygen cans, being pressurized cylinders, are universally disallowed in both carry-on and checked baggage. This is due to the inherent risks associated with pressurized containers in the aircraft's cargo hold or cabin. The cargo hold, in particular, experiences significant temperature fluctuations and potential for impact, making it an unsafe environment for such items. Even if a flight attendant were to permit a small cylinder, this would be a violation of safety regulations.
For approved Personal Oxygen Concentrators (POCs), the rules generally allow them to be brought into the cabin. However, they must meet specific size and weight requirements to fit under the seat in front of you or in the overhead bin. If a POC is too large to be stowed safely, the airline may not permit it onboard, even if it's an approved device. Passengers should always check the airline's dimensions for carry-on baggage and ensure their POC complies. If it cannot be stowed, it may be checked as baggage, but only if it meets the airline's specific guidelines for transporting medical equipment, which often still prohibits pressurized components.
The classification of your device is paramount. If you are bringing a device that is not a pressurized cylinder, confirm whether it is considered a 'medical device' or a 'piece of carry-on baggage.' This classification dictates where it can be stored and what rules apply. Airlines are very clear on this: pressurized containers are a no-go, while approved electronic medical devices require specific procedures.
TSA Regulations and Medical Oxygen
The Transportation Security Administration (TSA) plays a vital role in screening passengers and their belongings at airport security checkpoints. For medical oxygen, the TSA's primary concern is identifying and managing potential hazards. While the TSA does not prohibit medical oxygen, their regulations focus on the type of device and how it is presented for screening. Their guidelines are designed to work in conjunction with airline policies, ensuring a layered approach to safety.
The TSA explicitly states that passengers are allowed to travel with *approved* battery-powered medical devices, including certain types of oxygen equipment. However, compressed gas cylinders, which include standard oxygen cans, are forbidden. This aligns with the general prohibition by airlines and international aviation bodies. The TSA's role is to facilitate the screening process for passengers with medical needs while upholding security standards.
Screening Procedures for Oxygen Devices
When you arrive at the TSA checkpoint with an oxygen device, it is essential to declare it to a TSA officer. Do not attempt to conceal it or pass it through the screening machine without informing an officer. Typically, oxygen-related equipment, especially Personal Oxygen Concentrators (POCs), will require special handling. The device and its batteries may need to be screened separately. Officers may ask you to power on the device to verify it is functioning as a medical aid and not a prohibited item.
For passengers using POCs, the batteries often need to be removed and screened separately. They may also be subjected to additional screening. It is advisable to carry your POC in a case that allows for easy removal of batteries and accessories. Passengers should also be aware of the TSA's rules regarding spare batteries, particularly lithium-ion batteries, which have specific quantity and packaging requirements. Lithium batteries must be carried in carry-on baggage, and if they are loose, they must have their terminals protected to prevent short circuits.
The TSA officers are trained to handle passengers with disabilities and medical needs. If you have specific questions or concerns about the screening process for your oxygen device, do not hesitate to ask the officer. They can explain the procedures and ensure that your device is screened appropriately, minimizing any potential delays or complications during your journey through security.
Carry all necessary documentation, including a doctor's note and airline approval confirmation, readily accessible when approaching the TSA checkpoint.
What the TSA Allows and Prohibits
The TSA's stance is clear: compressed oxygen cylinders ('oxygen cans') are not permitted. This prohibition extends to both carry-on and checked baggage. The reason is the inherent danger associated with carrying pressurized gas on an aircraft. The agency focuses on ensuring that any medical devices brought onboard are safe and do not pose a threat to flight operations or passenger well-being.
Personal Oxygen Concentrators (POCs) are generally allowed, provided they meet TSA and airline requirements. This includes being in good working order and having batteries that can be screened. The TSA permits passengers to use their POCs during the flight, but only if the airline has approved its use. This means that even if the TSA clears your device through security, you still need the airline's go-ahead to use it once onboard.
It is important to remember that the TSA screens for security threats. While they facilitate travel for medical needs, their primary mandate is safety. Therefore, any item that could be construed as a safety hazard, including pressurized oxygen containers, will be confiscated. Passengers must ensure they are fully aware of both TSA and airline regulations before arriving at the airport to avoid any last-minute issues.
Alternatives and Solutions for Oxygen Needs During Flight
Given the strict prohibitions on compressed oxygen cylinders, passengers requiring supplemental oxygen must explore alternative solutions that comply with aviation safety regulations. The most common and widely accepted alternative is the use of a Personal Oxygen Concentrator (POC). These devices are designed for portability and continuous use, making them suitable for air travel, provided they meet airline and TSA specifications.
For individuals who do not regularly use oxygen therapy but experience ear discomfort or pressure changes during flight, there are non-medical strategies to alleviate these symptoms. These methods are often discussed in the context of how to pop ears after flight or how to unpop ears after flight, and they involve managing air pressure within the middle ear. Simple techniques like swallowing, yawning, or using chewing gum can help equalize pressure, offering relief without needing any medical devices.
Utilizing Personal Oxygen Concentrators (POCs)
POCs are the primary solution for travelers who need a continuous supply of oxygen. They work by drawing in ambient air, filtering out nitrogen, and delivering a concentrated oxygen stream. Modern POCs are lightweight, battery-powered, and designed for mobility. However, their use on flights is subject to airline approval, which typically requires advance notification and submission of medical documentation. Passengers must also ensure their POC's batteries are fully charged and that they carry sufficient spare batteries to last the entire journey, including potential delays. Many airlines have specific rules about the number and type of spare batteries allowed.
When selecting a POC for travel, consider its battery life, weight, and operational noise level. It is also beneficial to choose a model that has been approved by the airline you intend to fly with. Some airlines maintain a list of approved POC models on their websites. Always confirm that your specific device is permitted and understand the airline’s policy on using it during taxi, takeoff, and landing, as restrictions may apply to electronic device usage during these critical phases of flight.
Confirm the specific type of battery your POC uses and check airline regulations for limits on lithium-ion batteries, as these are common and have strict carriage rules.
Managing Ear Pressure Without Medical Oxygen
For the general traveler, ear discomfort is a common complaint, often described as ears being blocked after flight. This occurs because changes in cabin pressure affect the air pressure in the middle ear. The Eustachian tube, which connects the middle ear to the back of the throat, normally equalizes this pressure. However, during ascent and descent, rapid pressure changes can overwhelm its ability to function effectively, leading to that 'popped' or blocked sensation.
To avoid ear pain during flight, or to help unpop ears after flight, several techniques are recommended. Yawning or swallowing frequently helps to open the Eustachian tubes. Chewing gum or sucking on hard candy can stimulate swallowing. For infants, feeding them during descent can encourage swallowing. The Valsalva maneuver (gently blowing air into the nose while pinching it shut) can also help, but should be done cautiously. These methods are effective for most people and do not involve any prohibited items or medical oxygen.
Understanding how to get over flight fear or how to overcome flight fear is also important for many passengers, as anxiety can sometimes exacerbate physical discomforts. While not directly related to oxygen, managing stress can contribute to a more comfortable overall flight experience, potentially making ear pressure issues less bothersome.
What If You Cannot Use a POC?
If a POC is not suitable for a passenger's needs, or if an airline does not approve its use, the options become severely limited. In such rare cases, passengers may need to consult with their healthcare provider to discuss alternative strategies for managing their oxygen needs during travel. This might involve adjusting medication, considering shorter travel distances, or postponing travel until a suitable solution can be found. The safety of air travel for individuals with significant medical conditions is paramount, and airlines will prioritize this over accommodating a request that cannot be met safely.
It is also worth noting that certain conditions might affect travel suitability. For example, questions like 'can you flight while pregnant' or 'when can you flight pregnant' and 'for flight passengers who are pregnant' are addressed by specific medical guidelines, which may also influence the feasibility of carrying certain medical equipment. Pregnant passengers, especially those with complications, should always consult their doctor before booking flights and inquire about any specific airline policies for pregnant travelers.
Preparing for Your Flight: A Proactive Approach
Successful air travel with any medical requirement hinges on meticulous planning and proactive communication. For those needing supplemental oxygen, this means not just understanding the rules but actively engaging with the airline and preparing all necessary documentation well in advance. The goal is to preempt any potential issues that could arise at the airport or during the flight, ensuring a smooth and safe journey.
The first and most critical step is to identify your oxygen needs and the device that best meets them. If you require oxygen, discuss options with your physician, focusing on devices approved for air travel. Once you have a device in mind, or if you already use one, research the policies of the airline you intend to fly with. Do not assume that regulations are uniform across all carriers.
Pre-Flight Checklist for Oxygen Users
To ensure a hassle-free travel experience, consider the following checklist:
- Consult Your Doctor: Obtain a current doctor's note detailing your medical condition, prescribed oxygen levels, and fitness to fly.
- Choose the Right Device: Confirm your device is a Personal Oxygen Concentrator (POC), not a compressed cylinder.
- Airline Notification: Contact the airline at least 48 hours (or as per their policy) before your flight to declare your need for oxygen and get device approval.
- Documentation Ready: Keep your doctor's note and airline approval confirmation easily accessible.
- Battery Power: Ensure your POC batteries are fully charged and you have sufficient spares for the entire journey, adhering to airline limits.
- Device Size: Verify your POC fits airline carry-on dimensions for under-seat or overhead bin storage.
- TSA Awareness: Understand TSA screening procedures for medical devices and batteries.
- Emergency Plan: Know what to do if your device malfunctions or you experience discomfort.
This checklist serves as a comprehensive guide to cover all bases. Each point is designed to mitigate risk and ensure you are fully compliant with safety regulations. By addressing these aspects systematically, you can significantly reduce the chances of encountering problems at the airport.
Practice using your POC and its batteries in various settings before your trip to become comfortable with its operation and charging cycle.
Communicating with Airline Staff
When you communicate with airline staff, be clear, concise, and polite. State your name, flight details, and your requirement for supplemental oxygen. Provide the specific type of device you will be using (e.g., 'a battery-powered Personal Oxygen Concentrator, model XYZ'). Be prepared to provide the contact information for your physician if requested. If you are unsure about any part of their policy, ask for clarification and, if possible, request that the confirmation and any specific instructions be sent to you in writing via email.
During the flight, inform the flight attendant that you have an approved oxygen device. They will guide you on its use and ensure it does not interfere with onboard operations. If you experience any issues or need assistance, do not hesitate to alert the cabin crew immediately. Their primary concern is passenger safety and well-being, and they are trained to respond to medical situations.
Remember, the objective is to have a safe and comfortable flight. By taking these preparatory steps, you empower yourself with knowledge and ensure that your travel experience is as stress-free as possible, allowing you to focus on your destination rather than potential travel impediments.
Common Pitfalls and How to Avoid Them
Navigating the complexities of air travel with medical oxygen can present several challenges. Many passengers encounter issues not due to outright prohibition, but rather due to oversight, misunderstanding of regulations, or inadequate preparation. Recognizing these common pitfalls is the first step in ensuring you avoid them and have a seamless travel experience.
One of the most frequent mistakes is assuming that all portable oxygen devices are treated equally. As established, the critical distinction lies between pressurized cylinders ('oxygen cans') and electronic Personal Oxygen Concentrators (POCs). Travelers who arrive at the airport with a compressed oxygen cylinder, believing it to be a standard carry-on, will inevitably face denial of boarding. This is a strict safety regulation that is rarely, if ever, waived.
Mistaking Cylinders for Approved Devices
The primary pitfall is the confusion between compressed oxygen cylinders and Personal Oxygen Concentrators (POCs). Airlines and security agencies like the TSA have very clear rules: compressed gases in cylinders are classified as hazardous materials and are not allowed in the cabin or cargo hold. This is because the cylinders are pressurized and could rupture or leak, posing a significant fire risk or injury hazard in the event of an accident or rapid pressure changes. Therefore, attempting to bring 'oxygen cans' onto a flight is a guaranteed way to be denied boarding.
Passengers must understand that their physician's prescription is for the *need* for oxygen, not necessarily for a specific *type* of device that is airline-approved. It is the passenger's responsibility to ensure that the device they plan to use for travel is compliant with both airline and TSA regulations. This means selecting a battery-powered POC that has been approved by the airline and carrying all necessary medical documentation and airline confirmations.
The most important distinction is between a container of pressurized gas and a device that generates oxygen from the air.
Failure to Notify and Obtain Approval
Another common error is failing to notify the airline in advance and obtain explicit approval for the use of a POC. Airlines require passengers to declare their need for supplemental oxygen and the type of device they will use, typically at least 48 hours before departure. This notification period allows the airline to review the request, confirm device compatibility, and ensure that all safety and logistical requirements are met. Some airlines may also require a medical certificate from a physician.
Arriving at the airport without prior notification can lead to significant delays or denial of boarding. The airline staff at the gate may not have the authority or the time to process your request, especially if it involves verifying medical documentation or checking device specifications. It is essential to treat the airline's approval process as a mandatory step, not an optional one.
This process also applies to battery requirements. Airlines often have specific rules regarding the type and number of spare batteries allowed, particularly for lithium-ion batteries. Failing to adhere to these battery regulations can also result in your device being disallowed or confiscated. Always check the airline's policy on batteries for portable electronic devices.
Inadequate Battery Power and Planning
For POC users, battery life is a critical consideration. Flights can be long, and delays are common. Passengers must ensure that their POC has enough battery power to operate for the entire duration of the flight, including potential extended periods on the tarmac or during unforeseen layovers. This often means carrying multiple fully charged spare batteries.
A common pitfall is underestimating the total required battery time or not having a reliable way to charge batteries during transit or at the destination. Airlines may not provide charging facilities at gates or on board, especially for older aircraft. Therefore, passengers should calculate their total oxygen needs for the entire travel day (including travel to and from airports, flight time, and any layovers) and ensure they have sufficient battery capacity to cover this period. Carrying a portable power bank or a car charger, if applicable, can also be a lifesaver.
Regulations for Specific Passenger Groups
While the general rules about oxygen cans and approved POCs apply to most travelers, certain passenger groups may have additional considerations or specific regulations to be aware of. These often relate to underlying medical conditions, age, or specific life stages, which can influence travel advisories and the type of equipment or assistance required.
For instance, pregnant passengers, especially those with high-risk pregnancies, often have unique concerns when flying. While pregnancy itself does not typically preclude air travel, medical conditions associated with pregnancy might. These can impact the need for supplemental oxygen or necessitate specific precautions, making it crucial for expectant mothers to consult their healthcare providers and the airline.
Travel for Pregnant Passengers
The question 'can you flight while pregnant' is common, and generally, the answer is yes, particularly in the earlier stages. However, airlines and medical professionals often advise caution for pregnant passengers, especially in their third trimester. Specific concerns for pregnant passengers flying include deep vein thrombosis (DVT), premature labor, and the need for medical support. If a pregnant passenger requires supplemental oxygen, the standard rules for POCs apply, but they must also adhere to any airline-specific policies for pregnant travelers.
Airlines may require a doctor's letter confirming fitness to fly for pregnant passengers, particularly after a certain gestational age. This letter should address any specific conditions that might affect travel safety. For passengers who are pregnant and require oxygen, the physician's note should explicitly state the need for supplemental oxygen and confirm that a portable oxygen concentrator is medically appropriate and safe for use during the flight. Airlines may have additional guidelines for pregnant travelers, such as preferred seating or recommendations on cabin movement.
When considering travel for flight passengers who are pregnant, it's wise to book flights with direct routes to minimize the time spent in potentially uncomfortable cabin environments. Staying hydrated and moving regularly are also key recommendations, which are standard advice for all passengers but especially important for pregnant individuals.
Traveling with Children and Infants
Traveling with infants and children who require oxygen therapy presents its own set of challenges. Airlines generally permit the use of POCs for children, but specific approvals and procedures are often required. Parents must provide detailed medical information from the child's pediatrician, outlining the need for oxygen, the prescribed flow rate, and confirmation that the child can travel safely with the device. The POC itself must be airline-approved and suitable for pediatric use.
Some airlines may have specific policies regarding the use of oxygen devices by minors, including restrictions on battery usage or the need for an adult to be solely responsible for operating the device. It is crucial for parents to understand these rules well in advance. For infants, feeding during descent is often recommended to help equalize ear pressure, similar to how it's suggested for babies to help them unpop their ears after flight.
In all cases involving children, safety is the paramount concern. Airlines will err on the side of caution if there is any doubt about the child's ability to travel safely with the required equipment. Therefore, thorough preparation and clear communication with both medical professionals and the airline are indispensable.
Passengers with Other Medical Conditions
Beyond pregnancy and pediatric needs, many other medical conditions might necessitate the use of supplemental oxygen or require special consideration during air travel. This can include respiratory conditions like COPD or asthma, cardiovascular issues, or sleep apnea. For any passenger with a pre-existing medical condition, the process of securing approval for oxygen devices is similar: consult your physician, choose an approved device, and notify the airline well in advance.
It is also important to consider how conditions like claustrophobia or fear of flying might interact with the need for oxygen. While managing flight fear is a separate concern, having a reliable oxygen supply can sometimes alleviate anxiety for those with respiratory conditions. However, it is vital not to let the presence of an oxygen device become a source of additional stress. Proper planning and understanding of the rules are the best ways to ensure a calm and safe journey.
Airlines are equipped to handle a range of medical needs, but they rely on passengers to provide accurate information and follow established protocols. By understanding the restrictions on oxygen cans and the requirements for approved devices like POCs, passengers can prepare effectively and enjoy a more comfortable and secure travel experience.
Frequently Asked Questions About Oxygen on Flights
The regulations surrounding oxygen devices on flights can be intricate, leading to common questions from passengers. Understanding these FAQs can help clarify the rules and ensure travelers are well-prepared for their journey. The primary concern for both airlines and passengers is safety and compliance with aviation standards.
One of the most frequent points of confusion is the distinction between different types of oxygen equipment. While compressed oxygen cylinders, often called 'oxygen cans,' are universally prohibited, Personal Oxygen Concentrators (POCs) are frequently permitted, subject to airline approval and specific regulations. This distinction is fundamental to understanding what you can and cannot bring aboard an aircraft.
Can I bring my portable oxygen concentrator (POC) on the plane?
Yes, in most cases, you can bring an approved Personal Oxygen Concentrator (POC) on the plane. However, you must notify the airline in advance, typically at least 48 hours prior to departure, and provide necessary medical documentation. The airline must approve the specific POC model you intend to use, and you must comply with their rules regarding battery power and device usage during the flight.
Are compressed oxygen cylinders (oxygen cans) allowed on flights?
No, compressed oxygen cylinders, often referred to as 'oxygen cans,' are strictly prohibited on commercial flights. They are classified as hazardous materials due to their pressurized nature and the potential fire risk they pose. This rule applies to both carry-on and checked baggage and is enforced by airlines and aviation security agencies worldwide.
What documentation do I need to travel with a POC?
You will typically need a doctor's written statement confirming your need for supplemental oxygen, your fitness to fly, the prescribed flow rate, and that your specific POC model is suitable and in good working order. Airlines may also require you to complete their own specific medical forms. Always check your airline's exact requirements.
How much battery power do I need for my POC on a flight?
You must ensure your POC has enough battery power to last the entire flight duration, including any potential delays. Many airlines require you to carry sufficient spare batteries to cover the flight, and they may have limits on the number and type of batteries (especially lithium-ion) you can bring. It's crucial to calculate total power needs and confirm airline policies.
Can I use my POC during the flight?
Generally, if your POC has been approved by the airline and meets all their requirements, you will be permitted to use it during the flight. However, some airlines may have restrictions on using electronic devices during taxi, takeoff, and landing. Always confirm the specific usage rules with your airline before your flight.
What if my airline does not allow my POC?
If your airline does not permit your specific POC or if you cannot meet their requirements, you will need to consult with your physician to explore alternative oxygen solutions or consider postponing your travel. In rare cases, it may be possible to check the device as cargo, but this is highly unlikely for oxygen devices and depends entirely on the airline's specific policies for medical equipment.
What are the TSA rules for bringing oxygen on a plane?
The TSA allows approved battery-powered medical devices like POCs through security checkpoints. You must declare the device to a TSA officer, and it may require separate screening. Compressed oxygen cylinders are prohibited. The TSA screens for safety, and while they facilitate medical needs, they follow strict guidelines regarding pressurized containers and batteries.