Most of the decontamination will be carried out using the Zyme-Flow® Vapour-Phase® Process. This involves the simple process of injecting Zyme-Flow® chemistry into the steam source and following standard steam-out procedures. Zyme-Flow® will oxidize H2S very fast and oxidizes pyrophoric iron sulfide on contact. This oxidation is fast and safe and is non-exothermic. Zyme-Flow® will also allow benzene and hydrocarbon to be released to the flare much faster than steam alone saving turnaround time. After a Vapour-Phase® decontamination, what may be left behind in heavy oil towers is dried, de-oiled scale and debris that can be easily swept, vacuumed, or brushed out. Recommended final water rinses can help remove more of this debris prior to entry. These are also steps available to maximize the level of cleanliness and to reach pyrophorics. Zyme-Flow Decon Technology tailors the decontamination process and procedures to fit into the plants normal shutdown procedures as closely as possible. This makes it easier for planning and operations with as little change as necessary to plant standard shutdown procedures.