How does this heart rate monitor work?

Taking advice of many who recommend a heart rate monitor to improve your running, I bought a monitor several months ago. Fortunately, I got pregnant and was able to put off the idea of running for performance for several months. However, now that I am not pregnant and have no desire to go down that path again, I figured it was time to try this heart rate monitor. So, I go through all the effort of setting it up (the basic information) and I even read the manual. I think I tried using it a couple times, but the interval beeping wasn't loud enough for me to hear over my ipod so rather than take it out when I go for a run, I look at it and think: "I really need to figure that monitor out" and go out with my trusty timex.

Do I need to call poison control?

First, let me say that my husband is not a stupid man, actually he is quite intelligent. However, common sense seems to be something that he is a smidge short on. I don't say these things with anger or malice in my heart because I would say these things to my husband, and I have, repeatedly. For example, we have two kids Ayelet who is 7 months and Eytan who is 2.5. Hubs was playing with kids outside. I was in the house trying to clean things up because we have a Passover Seder planned and I need several days to get my house looking like I always keep it tidy (which, really with two little kids, my house is rarely tidy). At any rate, Hubs is in the backyard and he picks some tulips while holding Ayelet, little miss grabby hands. When they come inside, Ayelet has already pulled the flower off the stem and she is holding the stem while Hubs holds the flower portion. So, by the time I see them and Hubs is handing me the flower saying "Ayelet wanted to pick this for Momma" Ayelet was chewing on the stem portion. The first thing that crossed my mind is, what are you doing letting her chew on that? it could be poisonous. why aren't you paying more attention to my baby and what goes into her mouth? Argh. Good thing she didn't actually consume anything and all was fine.