The Shearwater Research upgrade to the DCIEM Algorithm for Commercial Diving is supported only by the current firmware version of your Shearwater Peregrine, Petrel2, Perdix, Perdix AI, or NERD2 dive computers when set in Air or single gas Nitrox mode. An unlock code to enable the feature in the firmware is returned to you via E-mail.
The Defence and Civil Institute of Environmental Medicine in Canada (DCIEM – now Defence Research and Development Canada or DRDC) developed their serial decompression model based on decades of research which began with the studies by Kidd and Stubbs. Unlike parallel models typically used in dive computers, where gas diffusion is assumed to occur independently in each compartment, serial decompression models assume that gas transfers simultaneously between the compartments. Only one compartment is assumed to be exposed to ambient pressure. The DCIEM model is based on four compartments and these compartments do not use set halftimes, instead each compartment diffuses differently depending on depth and time. See the Product Attachments tab above to view a Canadian government funded document describing the DCIEM decompression procedures in more detail.
The DCIEM decompression model has been extensively validated with strenuous cold-water single-gas diving and is believed to be safer than those of the US Navy and UK Royal Navy. DCIEM is a relatively conservative decompression model that is proven to be well suited to scientific and commercial types of diving.
The DRDC worked closely with Shearwater to ensure their dive computer implementation is true to the DCIEM model. The Shearwater DCIEM implementation does not produce Repetitive Groups or Repetitive Factors as with the tables; instead the algorithm constantly updates the actual decompression profile in real time during the dive and surface intervals. The diver can access both the ZHL-16C algorithm and the DCIEM algorithm calculations on the same dive computer and switch between diving algorithms while on the surface.
Shearwater Research Upgrade to DCIEM Algorithm Features
- Switch between ZHL-16C algorithm and the DCIEM algorithm calculations
- DCIEM is proven to be well suited to Commercial Diving activities
- Supported by Shearwater Peregrine, Petrel2, Perdix, Perdix AI, or NERD2 dive computers
- We email an unlock code to you after purchase
- Available only in Air or single gas Nitrox modes
You will receive your DCIEM code as soon as possible. The controlling factor is the exact time of day you place your order and how that relates to Shearwater's office hours. The DCIEM code is generated manually from your serial number by the Shearwater office staff.