Excerpt from:
DENR Memorandum Circular
No. 2021 – 13
Dec. 03, 2021
SECTION 2. Caves are classified according to the following categories:
Class 1. Cave Classification. Caves with delicate and fragile geological formations, threatened species, archaeological and paleontological values and extremely hazardous conditions. Allowable activities are limited to mapping, photography, educational and scientific purposes and closed for ecotourism activities.
Class 1 caves are further classified into:
Class 1 A Caves with delicate and fragile geological formations/archaeological values/paleontological values;
Class 1 B Caves with threatened species;
Class 1 C Caves with extremely hazardous conditions (e.g. bad air, unstable ceiling, presence of rock fall / breakdown , etc.);
Class 1 D Caves with A, B, and C;
Class 1 E Caves with A and B;
Class 1 F Caves with A and C; and
Class 1 G Caves with B and C
Class II. Caves with areas or portions which have hazardous conditions and contain sensitive geological, archaeological, cultural, historical and biological values or high-quality ecosystems. It may be necessary to close sections of these caves seasonally or permanently. It is open to experienced cavern pr guided educational tours/ visits.
Class III. Caves with no known threatened species and archaeological, geological, natural history, cultural and historical values. It is safe to inexperienced visitors but should still be accompanied by cave guide/s. The caves may also be utilized, when appropriate for other economic purposes such as guano extraction and edible birds nest collection.
Filipino Cave Divers 