Methane is an extremely flammable gas that can cause explosions and asphyxiation. It is also a simple asphyxiant, meaning it can displace oxygen and cause rapid suffocation. [4] [6]

Here are safety procedures and regulatory guidelines for handling methane gas:

Engineering controls:

• Use local exhaust ventilation if general ventilation is not adequate.
• Utilize non-sparking ventilation systems.
• Approved explosion-proof equipment and intrinsically safe electrical systems should be used in areas where methane is handled and stored.
• Prevent accumulation of methane in work or storage areas, especially confined spaces.
• For large-scale use, implement stringent control measures such as process enclosure to prevent release into the workplace.

[1] Personal Protective Equipment (PPE):

• Wear chemical safety goggles and a face shield when contact is possible.
• Always wear insulated protective clothing if contact with refrigerated gas is possible.
• Respiratory protection is not normally required, but approved respiratory protection should be readily available in areas of potential oxygen deficiency or equipment failure.
• For entry into unknown concentrations or areas with less than 18% oxygen, use a self-contained breathing apparatus with a full facepiece operated in a pressure-demand or positive-pressure mode.

[1] [8] Handling and storage practices:

• Eliminate heat and ignition sources such as sparks, open flames, hot surfaces, and static discharge.
• Post "No Smoking" signs.
• If used in a confined space, check for oxygen deficiency before worker entry and during work.
• Secure cylinders in an upright position and protect them from damage.
• Use a suitable hand truck to move cylinders; do not drag, roll, slide, or drop.
• Prevent unintentional contact with incompatible chemicals.
• Store in a cool, well-ventilated, and temperature-controlled area, away from direct sunlight and heat and ignition sources.
• Keep away from combustible and flammable materials.
• Separate from incompatible materials such as strong oxidizing agents and halogens.
• Always secure cylinders in an upright position to a wall, rack, or other solid structure.

[3] [3] Unintentional release measures:

• Evacuate the area immediately and isolate the hazard area.
• Eliminate all ignition sources and use grounded, explosion-proof equipment.
• Stop or reduce the leak if safe to do so.
• Knock down vapor with fog or fine water spray.
• Ventilate the area to prevent gas accumulation, especially in confined spaces.

[3] Firefighting measures:

• Use water spray, alcohol-resistant foam, dry chemical, or carbon dioxide to extinguish fires.
• Wear self-contained breathing apparatus for firefighting if necessary.
• Use water spray to cool unopened containers.

[2] First aid measures:

• Inhalation: Move the person to fresh air. If not breathing, give artificial respiration. Consult a physician.
• Skin contact: Wash off with soap and plenty of water. Consult a physician. For liquefied gas exposure, quickly remove the victim from the source of contamination and get medical attention immediately.
• Eye contact: Flush eyes with water as a precaution. For liquefied gas exposure, immediately flush with gently flowing water and get medical attention immediately.
• Ingestion: Do NOT induce vomiting. Rinse mouth with water and consult a physician.

[4] [7] Exposure limits:

• ACGIH TLV-TWA: Minimal oxygen content required. Simple asphyxiant. Explosion hazard: excursions above the TLV could approach 10% of the lower explosion limit.
• USA NIOSH Recommended Exposure Limits: TWA 0.1 mg/m3

[1] [5] Methane is classified as a flammable gas, a compressed gas, and a simple asphyxiant. [6]