In certain cases – usually in remote areas – it is possible to burn off spilled oil "in situ" (Latin for "in place"). Burning can eliminate large volumes of oil quickly and effectively; however, it also burns off plant life and leaves residue that can adversely affect the ecosystem. Special fire-resistant booms must be used to contain open-water burns, as burning oil may spread rapidly in water. When conducting in-situ burning on land, berms or trenches serve a similar containment function as fire-resistant booms. In some cases, the contained spill area is flooded in order to raise the burning oil off the vegetation below.
The decision to burn should be made early in an incident, taking into account its feasibility and appropriateness and with guidance from Incident Command/Unified Command to make best use of windows of opportunity. Field Guides are available for both inland and on-water responses. These guides contain a set of operational checklists, tools, and references to assist in the conduct of in-situ burning of spilled oil. They are intended for experienced response operations personnel having basic knowledge or expertise in ISB.