The following are good reasons why you should not dive.
  1. You are uncertified.  Being uncertified could easily place you in a situation that could cause you physical harm or even death.
  2. You are tired.  We have all been diving when we were tired but the problem is that we can become disorientated and end up injured or causing someone else to be injured so be sure you.
  3. You are dehydrated.  A 2% loss of body weight will severely affect a person's performance.  Sounds like a lot but just the loss of one quart of fluids can equal a two pound loss in weight.  Be sure you drink plenty of fluids to keep yourself hydrated when you are diving and after your dive be sure you replenish yourself.
  4. Your are sick, have sinus congestion, a runny nose, fever, etc.  Illness has many effects on you normally but when you are diving you are placing yourself into a different medium that well have a direct effect on your body.  Take a day off and enjoy yourself.
  5. You have trouble clearing your Eustachian tubes ("equalizing" when descending or ascending).  Dangers here are the potential of breaking an ear drum and possibly causing you not to be able to dive for a long time or ever again.  It's not worth taking the chance.
  6. Your scuba gear is not working.  You should never dive if your gear is not working.  This means if any of your gear has a leak, your tank is out of date for its hydro, or straps are cracked.
  7. If your nitrogen level is too high be sure to take an adequate surface break.  Be conservative and take your needed breaks between dives.  Re-hydrate yourself, have something to eat and enjoy the scenery on the surface.
  8. The water is choppy, rough or visibility is poor.  Yes you can dive in these conditions but ask yourself if it is worth the effort and well you really enjoy being tossed around?
  9. You have no buddy to dive with.  Yes there are those who dive alone but you well not be save and when a situation arises that you need help is your life worth taking that risk?
  10. You are under the influence of drugs or alcohol.  This means over the counter medications, herbal remedies as well as prescription drugs and alcohol.
  11. You have a preexisting health problem that may present a hazard when you are diving.
  12. You are short of breath, asthmatic or have problems with allergies.  Remember you only have the air on your back and as you dive the atmospheric pressure will increase by one atmosphere every 33 feet of depth increasing your difficulty to breath.