The other day I had a customer call me and ask me the difference between Fire Tested and Fire Safe Design, I answered him the best that I could based on my own acquired knowledge however I thought this would be something for me to blog about so that I could learn more about it. Here is what I learned:
Top Level: Fire Safe Tested Valves: Valves built and tested (with fire at given intensity and time and with following operational and leakage tests) according to a given Firesafe standard. The standards will accept within limitatations equally constructed valves in near pressure classes and sizes as 'Firesafe tested' if the Firesafe test for one size and pressure class is passed.
The customer will either accept an earlier passed test or require a new test for a certain (bulk) order of 'Firesafe tested' valves, within the range described, as a part of the contract.
Middle Level: 'Firesafe Design' from a factory that have at an earlier time fire tested with passing results equally constructed valves (according to a given Firesafe standard), but where the actual valve size or pressure class (or near sizes and pressure classes as allowed under the given standard) have not been tested earlier. (Usually for economical or time-consuming reasons, or because standards does not include the sizes or pressure classes.) Tests may or may not be required from the customer, with or without economical compensation (according to market competition, risk evaluation and cost).
Bottom Level: Firesafe design from a factory not actually at any time having Firesafe tested a valve, or with 'Firesafe' tests with weak actual quality or relevance, and/or large deviations in construction.
Source: Eng-Tips Forums, Intelligent Works Forums For Engineering Professionals