Q. I use an Apple Macintosh in the office, but many of my business associates use IBM PCs and compatibles. All use the 3.5-inch disk format.

Several of my clients have sent me disks containing their documents and Lotus 1-2-3 spreadsheets, but my Mac won't read the IBM disks. Is there an inexpensive way to get my Macintosh to read the data on these disks into my Macintosh applications?

A. Although IBMs and Macs are directly incompatible with each other, there is a way to get your Mac to read those IBM disks. There are two hurdles to overcome, and one utility program can overcome both.

First, IBMs and Macs write their information to the disk differently. Both use invisible magnetic circular rings that are similar in performance to grooves on a record. These concentric tracks organize and contain the disk's data, but the IBM and Mac position and structure them differently.

Fortunately, most of the 3.5-inch disk drives used by both computers are physically capable of reading tracks no matter where they have been placed. You just need the proper software to tell these drives where the tracks are located and how to correctly read the data that's there.

The two most popular programs that allow a Mac to read an IBM disk are Insignia Solution's "Access PC 1.1" ($129), and Dayna's "DOS Mounter 2.0" ($89.95). Both have been upgraded recently, and their features are nearly identical.

With either program, when an IBM disk is inserted into a Mac drive, it is treated as a regular Mac disk. Instead of getting the message that says the disk is unreadable, a picture of a little disk appears on the screen. All of the data is displayed as little pictures, or icons. IBM subdirectories appear as Mac folders, because conceptually they are both the same. And you can manipulate (move, copy, delete) the data in the same way as Mac data.

The second hurdle is the data itself. Even if your Mac's drive can read the data, can your application program process it? A few of the major Macintosh programs can. Microsoft's Excel spreadsheet program can translate and use the data contained in a Lotus 1-2-3 spreadsheet file. Another example is Claris's MacWrite II, which can translate and use several of the popular IBM word-processing program formats such as Word Perfect and Microsoft Word.

Utility programs also allow you to "map," or link, documents to the Macintosh application that will use them. For example, you can tell DOS Mounter to map every Lotus file to Microsoft Excel. Then, running any Lotus file will automatically start the Excel program and translate the Lotus file into Excel.

(Dayna Communication Inc., 801-531-0600; Insignia Solutions Inc., 408-522-7600)

Q. I've been hearing about dangerous ELF radiation being emitted from computer video display terminals. Is this something I should be worried about?

A. So far, there is no conclusive evidence regarding the long-term effects of constant exposure to nonionizing electromagnetic radiation (EMR).

Most video display terminals emit nonionizing EMR across a wide band of frequencies. This spectrum ranges from Extremely Low Frequency (ELF) through Very Low Frequency and continuing up through the microwave range and above.

What all of this alphabet soup means to you, the computer user, isn't exactly clear yet. But if you don't want to take any chances, there are several companies that make transparent shields that cover a display screen.

NoRad says its radiation shield ($129-$139) reduces electric radiation by more than 99.99 percent and the higher-frequency magnetic radiation by more than 50 percent. It also eliminates static electricity, glare and reflections.

(NoRad Corp., 1-800-262-3260; 213-395-0800)

Send questions to Craig Crossman, Business Monday, 1 Herald Plaza, Miami, Fla. 33132. Please include your phone number.