How much of a risk do micrometeorites pose to astronauts?
WAG: provided the suits used have the maximum amount of protection available, there is minimal risk.
From this site:
…every craft sent into orbit gets whacked repeatedly, most often by debris or micrometeorites no larger than a grain of sand. When American astronaut David Wolf was on board Mir in 1997, the space station lost power for a time, and he could hear micrometeorites skittering against the outer walls like hail.
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By analyzing the material clinging to the [space shuttle] windows with an electron microscope, researchers have found that 35 percent of the debris involved in the collisions is aluminum, 17 percent is paint, 11 percent is steel, and 4 percent is copper. Micrometeorites account for about 33 percent of the collisions, but they’re less than half as dense as aluminum and so are relatively harmless.
However, who would seriously hold a spacewalk in a micrometeorite shower? Each individual particle may be low risk, but a storm of them might be something else again.