Goggles
Goggles are an incredibly important piece of safety gear when snowboarding. Not only do they prevent snow, rain, or ice from getting in your eyes; they also can be used to shield your eyes from the sun depending on what lenses are in the goggles. Certain makes and models of snowboarding goggles can allow for swappable lenses to adapt to changing conditions. Lenses can range from completely transparent to dark enough to only transmit 5% of the light to your eyes. Also, lenses can come in a variety of colors in order to allow for better visibility in different conditions.
Helmets
A helmet is a necessary for mitigating the effects of a head impact during a fall. Without a helmet you are incredibly susceptible to concussion, skull fracture, or worse. When buying a new helmet, it's important that your helmet fits, and fits good. A loose helmet wont be as efficient in protecting you and a tight helmet can be uncomfortable to ride in. It's also important to factor in other things like having a camera mount, liners, goggle compatibility, and vents. It's also important for a helmet to have the ASTM F2040 certification. This certification is a common snow helmet certification found in the United States.
Other Protection
For beginner or advanced riders, protective pads, wrist guards, and elbow and knee pads can all be worn in order to prevent injury during a fall. Protective trousers with built in pads around the hips and tailbone can be worn to protect you from a backwards or sideways fall. Elbow and knee pads are a simple and efficient way to prevent minor bumps and bruises. Wrist guards are one of the most important for beginner riders. Most beginners don't know how to safely fall to the ground and often end up trying to fall onto their wrists. This can easily lead to a broken or sprained wrist, but wrist guards can help to prevent this.