Blue Grotto Dive Resort

Cavern Limits

What defines a cavern dive?

Most people who visit Blue Grotto know that it is a cavern dive. Not everyone, however, knows what this means. In this article, we’ll explore what defines a cavern dive and why you can dive Blue Grotto when you may not be able to explore other underwater caverns.

Caverns vs. open water diving

The thing that makes open-water diving so safe is that, should you bottom out your tank at depth, you can still make it to the surface just by exhaling a steady stream of bubbles. This is because, in open water, there is nothing between you and the surface.

However, as soon as you enter an overhead environment, this changes. A physical barrier prevents you from taking advantage of open water diving’s greatest safety feature. Doing so entails greater risk.

Cavern diving is defined as exploring natural overhead environments within sight of daylight. Anything beyond this is a cave dive.

Cavern diving limits

According to the major cave and technical organizations, sport divers must stay within the following cavern diving limits:

  • You must be able to see the exit clearly at all times.
  • You must be no more than 60 m/200 ft from breathable air at the surface.
  • You must remain within the recommended sport-diving depth limit of 30 m/100 ft.

Individual training agencies may have additional requirements. For example, the NSS-CDS specifies a minimum starting visibility of 12 m/40 ft.

Four ways to cavern dive safely

Of course, nothing in life is perfectly safe. There is an element of risk involved in simply driving to and from the dive site. However, you can cavern dive with a high degree of safety by doing any of the following:

  • Don’t take a light: Without one, it’s unlikely you will be able to penetrate a cavern far enough to get into trouble. This is known as the No-Lights Rule and is in effect at Florida State Parks for any diver lacking Cavern or Cave Diver certification.
  • Go with a qualified guide: In the USA, this would be a certified Cavern or Cave Diving Instructor.
  • Become a certified Cavern or Cave Diver: This will enable you to dive within the limits of your training without needing a guide.
  • Dive one of the four north-central Florida dive sites where Cavern or Cave Diver certification is not required: This requires some explanation.

Before formal Cavern Diver training was available, there was a broad consensus that certified divers with good buoyancy skills could safely dive the following north-central Florida caverns without additional training. These are:

  • Ginnie Spring (the Ballroom)
  • Devil’s Den
  • Blue Grotto
  • Paradise Spring

What do these sites have in common?

  • They are commercially operated, with rules to which visiting divers must adhere.
  • For the most part, they do not connect to a maze of underwater cave passageways in which divers could become easily lost.
  • They have a very good track record, with no more incidents than might occur at a typical open-water dive site.

This is why we invite any certified diver with good buoyancy skills to explore our cavern and experience the breathtaking views it provides.