Redoubt has shown us that some ash must fall and some might fall on Anchorage in the not too distant future - remember as you are protecting your computer equipment, you also need to protect your family members, your pets, and even your car - follow this link to learn more about protecting yourself, your faily, and your things. 

I hear that Redoubt volcano might erupt and ash might fall in my area - how do I prepare my Mac?

All modern electronic equipment is susceptible to ash fallout - volcanic ash contains sulphur and iron - the iron can conduct electricity and the sulphur can turn into sulphuric acid - bad stuff. So it is best to keep all such technology out of harms way - in this case volcanic ash.

So until you see volcanic ash in your area don't worry - once ash is falling in your area, I would recommend turning off all technology and if possible, I would wrap the equipment in plastic. What technology would I turn off and wrap:

• Computers
• Laptops
• Printers
• Monitors
• Keyboards & Mice
• Laptops
• TVs, VCRs, DVRs, cable boxes
• UPS
• Basically anything that is electric, has air vent holes, and/or uses air for cooling 

How long do I go without my Mac fix? As long as it takes for the ash to settle.

Once the fallout stops, use a vacuum to gather up all the ash on the plastic and around the equipment. I would then use compressed air to blow out the equipment, just to be sure. Next I would power up each piece of equipment and carefully observe its operation to be sure that there are no problems.

Good luck