The OEM whose products must operate in environments of extreme heat or extreme cold will find COTS solutions that counter these harsh environments in innovative ways. In an extremely hot environment electronic assemblies must effectively dissipate tremendous amounts of heat as well as balance the thermal stresses created by different materials. COTS thermal management alternatives include fans, heat pipes and cold plates. At the board level, manufacturers can add a metal layer to the PCB to conduct heat away from the board, although this is a very expensive alternative. Alternative convection thermal management solutions often consist of conduction blocks and extruded aluminum heat sinks with fins. Fans present a more traditional solution, but can have a negative impact on system reliability due to the wear associated with moving parts.

Typical market applications that use COTS boards.
Extreme cold provides its own set of challenges. In extreme cold, failure to boot and inaccurate analog readings may be the result of the intolerance of some components for low temperatures. When operating at -20°C and below, solutions include leaving the system running in order to self-heat or putting small electrical heaters within the system enclosure.

Protection of COTS products in harsh environments may also need to be addressed through the system packaging processes. The industry trend is toward increased component density and functionality to decrease system footprint and the use of more powerful microprocessors to increase performance. This trend makes thermal management at the board level more and more difficult to achieve. Therefore, optimal design and thermal management within a limited space may be handled best at the enclosure level rather than the board level. However, in the final analysis it is the OEM design engineer's responsibility to either select the appropriate COTS solution for a specific application or to modify the system environment by heating or cooling the enclosure.

Long-term product availability is always an issue when designing for embedded systems, and this doesn't change when designing for harsh environments. Desktop and commercial electronic components typically have a lifecycle of only twelve to eighteen months — the extreme opposite of typical SBCs for industrial embedded applications, where manufacturers need five to ten year availability. The increasing density and functionality of commercial board-level products exacerbates the problem of product obsolescence. The number of parts that can become unavailable increases with the number of features and components designed into a board. As a result, the potential of part obsolescence when choosing a COTS solution must be compared to using fully custom or proprietary products. But system cost, scheduling, and performance requirements can balance these risks. COTS manufacturers can work with the OEM to secure enough components to meet future demand. If the risk of obsolescence can be addressed early in this manner, the upside potential of reduced cost and increased performance can often influence the decision toward a COTS solution.