PSA Requirements

There are no PSA requirements for licensing the current generation of nuclear power plants, i (PRA to the NRC) has been a tool for regulatory decisions b] 

10CFR50.54(f) states that the licensee must submit individual plant examinations (IPE) of nificant. safety issues to justify continuing operation of a reactor facility. The NRC issued leric 

Chemical regulation is primarily concerned with the consequences to the public that may lit from ch— -iJ releases to the environment. Note there is less concern with the probability 1 with the c quences of release. The major U. S. environmental laws are as follov 

The Clean Air Act is the comprehensive Federal law that regulates air en stationary, and mobile sources. This law authorizes the U.S. Environmental Protection Agency (EPA) to establish National Ambient Air Quality Standards (NAAQS) to protect public health and the environment. The goal of the Act was to set and achieve NAAQS in every state by 1975. This ng of maximum pollutant standards was coupled with directing the states to develop state 

Author s note - The accident at TMI-1 released radioactivity far below lOCFR criteria till the licen was subject to severe regulatory action and suffered severe financial loss. 

---

It is worth noting that occasionally high Tg compatible additives are incorporated into the polystyrene phase, when the PSA requires higher temperature performance. These additives are usually based on poly-a-methylstyrene. 

NR pressure-sensitive adhesives with a high tackifier content can be used as commercial tapes and surgical plasters. These PSA require the elimination of the gel fraction and a reduction in molecular weight to facilitate solution. 

In addition to heat resistance, PF is also used to improve the solvent resistance of PSA. Formulas for attaining this property are similar to the one in Table 13, but would contain 20-30 parts of phenolic resin rather than 10. Such PSAs require cure times up to 3 h at 150°C. 

In recent years, designs have been used that do not require heat energy and depend only upon pressure swings to desorb water and C02. Pressure swing adsorbers (PSAs) require more adsorbent and regeneration flow than TSAs but save on long-term operating costs. 

A high tran.sfer rate, i.e, a high value of Psa. requires a considerable amount of ... 

The greatest asset to membrane separation is simplicity. And it makes them very attractive in applications where product demand is not constant. Whereas PSA requires the equipment for swinging pressure, cryogenic distillation must endure extreme temperatures, and absorption requires huge amount of sorbent, the only equipment necessary for GS is the membrane and fans. There are almost no moving parts, and the construction is fairly simple. The gaseous stream to be separated generally requires a compression, but this is much smaller than that necessary for PSA. 

Membrane technology is most often listed as potential candidate for its application in new plants for GS. The greatest asset to membrane separation is simplicity. Whereas PSA requires the equipment for swinging pressure. 

With MERMOS we propose to consider EOCs at the meso-level of the Operating System, the systemic level of interaction of Crew, Procedure and Interface. At that level aU erroneous behaviors are EOCs that leads to an EOO at the macro-level of the functional description of the PSA requirements. 

The NORSOK standards are developed by the Norwegian petroleum industry, and the NORSOK standard Z-013 presents some general requirements regarding the formulation of RAC, see NORSOK (2001). This standard does not provide any guidelines on what actual values to choose for RAC, which is in line with the basic Norwegian PSA requirements, which require that the operators should formulate their own risk acceptance criteria. 

The final step in the screening process is re-grouping of POSs and initiators. The result of the whole process is a list of safety important POSs and IE groups. The SLP PSA requires iterative processing for redefining and re-grouping POSs and lEs several times during the process. 

Development of accident sequence models for SLP PSA requires a close co-operation between plant personnel who are familiar with an outage and PSA analysts to assure that the all possible scenarios are appropriately modelled. Available accident mitigation measures may be much broader that for the power PSAs. The systems and the plant features which have been credited in power PSA may not be available for shutdown mode (as an example, heat removal using steam generators). The development of sequences should be an iterative process to adequately model sequences which represent actual plant configuration. 

---