The Lava Zone map was created in the 1970s to help landowners acquire insurance for their homes. Prior to that, insurance companies were reluctant to cover homes anywhere on the Big Island, for fear that the volcano would spew lava all over the place and they'd be out large amounts of money. The concept of the map was to simplify the volcano for the insurance industry. Although quite a bit has changed since the '70s, the map, with a revision in 1987, remains mostly the same.
Areas where lava had covered 25% of the land since 1800 were designated Lava Zone 1. If lava had covered 15-25% of the land, it was designated Lava Zone 2. And henceforth. Homeowner's Insurance is available for homes in Lava Zones 1 and 2, but the costs are higher than for zones 3 and up.
Since 1984, Pu'u O'o has been active and emitting lava. The land that it has been covering since has been in Lava Zones 2 and 3. It took 4 years for the Pu'u O'o flow to make it to the community of Kalapana Gardens and it took out approximately 40 homes, including the one that made front page news in December of 1989 that belonged to my previous partner Bill's parents. See "Featured Listings" for Bill's hilltop 32 acres with an ancient crater on it and incredible ocean view.
We both live in Lava Zone 1 and love it. We have steam vents on our properties that smell sweet and alive. Cinder cones that were created in the 1954 flow have caverns where the lava drained away that are coated with amazingly diverse crystals. We've rappelled down to see them, and it's a real treat. The geology of this young part of the earth is astounding.