Probably not exactly the same since "passaggi" indicates the number of time the ad is aired rather than how long it was on air, but depending on context you might get away with it.

That would be the most colloquial. If you wanted to be formal, you could say "radio transmissions".

Hi Sherry
I would use "runs" for "passaggi" but "radio runs" sounds weird ..

http://tinyurl.com/2hxnvy
On a 30 second radio ad they normally test the following criteria:
Time of day it airs
Adjacent programming
Man or woman announcing
Serious or comedic delivery
Fast or slow delivery
Leading paragraph
**Frequency of ad on the air (times it runs per day)**
Day of the week
Week of the month
Month of the year




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Note added at 3 hrs (2007-07-02 19:07:42 GMT)
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http://www.e-topic.com/forums/showthread.php?p=4809
Here is what you get. A professionally scripted and voiced promo (between 20 and 30 seconds long) that will run according to your package purchase, a full monthly report that documents each time your promo runs, full support through phone, e-mail, and a ton of exposure to further your business!

Weekly
$5 - Peak times - Number of Runs a Day = 3
$7 - Worldwide peak times - Number of Runs a Day = 6
$10 - Continuous 24-hour rotation, Sunday thru Saturday- Number of Runs a Day = 12