Describe the procedures and safety protocols involved in performing an Extra-Vehicular Activity (EVA) or spacewalk.

Performing an Extra-Vehicular Activity (EVA), commonly known as a spacewalk, is a complex and highly regulated operation conducted by astronauts outside their spacecraft in the vacuum of space. Several procedures and safety protocols are in place to ensure the safety and success of EVAs. Here is an in-depth description of the procedures and safety protocols involved in performing a spacewalk:

1. EVA Suit Preparation: Prior to an EVA, astronauts undergo thorough training and preparation to don their Extravehicular Mobility Units (EMUs), also known as spacesuits. The suits are meticulously checked, tested, and customized for each astronaut. This involves verifying the integrity of the suit's life support systems, communications systems, thermal control, and mobility components. Astronauts also receive comprehensive training on how to don and doff the suits correctly.
2. Airlock Preparation: The EVA usually begins by venturing into the airlock chamber, a small sealed compartment located on the spacecraft. Inside the airlock, the atmospheric pressure is reduced to match the pressure of the space environment. This process, known as pre-breathe, helps prevent decompression sickness (the bends) caused by nitrogen bubbles forming in the bloodstream. Astronauts spend several hours pre-breathing oxygen-rich gases to purge nitrogen from their bodies.
3. Crew Lock Depressurization: Once the pre-breathe process is complete, the airlock's interior is gradually depressurized to the vacuum of space. Depressurization is carefully monitored to prevent sudden pressure differentials and ensure the astronauts' safety. As the airlock pressure decreases, the astronauts' suits are checked for any leaks or malfunctions.
4. Hatch Opening: After reaching the desired external pressure, the hatch connecting the airlock to the outside of the spacecraft is opened. Astronauts use specialized tools and procedures to carefully unlock and open the hatch, ensuring it is secure and properly sealed. The hatch opening is a critical step, and the crew inside the spacecraft closely monitors the process.
5. Safety Tethering: Once outside the spacecraft, astronauts are tethered to it using strong and flexible safety tethers. These tethers prevent accidental drifting away from the spacecraft and serve as a lifeline for the astronauts. Astronauts are trained to secure themselves to various anchor points and move deliberately to prevent entanglement or snagging of the tethers.
6. Tools and Equipment Handling: During the spacewalk, astronauts carry a range of tools, equipment, and payloads necessary for their assigned tasks. They use specially designed tethers, restraints, and carrying devices to secure and handle these items. Careful attention is paid to prevent any loose objects from floating away and becoming potential hazards to the astronauts or the spacecraft.
7. Communication and Coordination: Continuous communication between the spacewalkers and the mission control center is maintained throughout the EVA. Astronauts use helmet-mounted communication devices and follow pre-established protocols for reporting their status, providing task updates, and addressing any unforeseen circumstances or emergencies.
8. Task Execution: Astronauts perform a variety of tasks during a spacewalk, including scientific experiments, repairs, maintenance, assembly, or construction activities. They rely on their extensive training and rehearsed procedures to execute these tasks efficiently while adhering to strict safety guidelines. The crew on the ground monitors the progress and provides guidance as needed.
9. Contingency Plans and Emergency Procedures: EVAs are planned with multiple contingency scenarios in mind. Astronauts and mission control establish emergency procedures to address various potential issues, such as equipment malfunctions, suit leaks, or emergencies requiring immediate return to the spacecraft. These procedures include emergency reentry plans, emergency oxygen supplies, and rescue scenarios.
10. Return and Reentry: After completing the assigned tasks