Safe life

US Army gun propellant and rocket propellants to support and advise field surveillance activities of the safe life potential and/or possible degradation of both bulk stored material and items using these propellants -... 

II) M. Roth, M. Laccetti M.R. Youngiver, PicArsnTechMemo GL-8-59(1959). "Abridged Spectrophotometrie Method for the Determination of Available Stabilizer Content and Application to Prediction of Safe Life of Propellants"... 

At one time it was believed (Ref 3) that detonability was detd by the burning rate. It must be understood clearly that high order detonation is a bulk phenomenon and not one governed by the classic proplnt burning theories. The tendency to detonate is a characteristic intrinsic with each formulation which must be studied in shock environments as it is found in a card gap or flyer plate test (see later in this article) or Susan and Wenograd tests (Ref 19) Likewise, density is not a useful measure of the detonability of a proplnt except perhaps to the extent that low density formulations may be porous. A more valid measure of the safe-life of proplnts is the depletion with time of stabilizers such as the nitroamines which are found in double base proplnts or the loss of the plasticizer. Such determinations can now be performed routinely in a quantitative fashion by means of liq chromatography Nuclear Radiation Hazard... 

In order to relate the critical size of the expl to its storage temp, an analytical solution is also available, provided that kinetic and thermal transport data are known (see below). All extrapolations of high temp data to storage temp data are subject to great uncertainty (Ref 32) which has contributed at times to a lively debate regarding the safe-life prediction of large solid proplnt motors... 

In fact, providing a safe, life-sustaining environment for fish involves a variety of complex, interdependent factors. Many of these are directly related to chemistry. For example, the presence of ammonia, NH3, is one of the most common causes of death in poorly maintained fish tanks. Ammonia is produced when uneaten fish food decays. This compound dissolves readily in water. It is toxic to fish in even minute concentrations. 

Complying with local and international standards (DIN, UNI, UNE, BS, ASTM) regarding mechanical and physical properties to ensure a safe life without unexpected failure and meet hygienic requirements (ANSI, NSF) to avoid health effects. 

Harlow, D. G., and Wei, R. P., Linkage Between Safe-Life and Crack Growth Approaches for Fatigue Life Prediction, in Materials Lifetime Science Engineering, P. K. Liaw, R. A. Buchanan, D. L. Klarstrom, R. P. Wei, D. G. Harlow, and P. F. Tortorelli, eds.. The Minerals, Metals Materials Society, Warrendale, PA (2003). 

Further irradiations were performed with the cast double-base proplnts ARP, ALL, and AHH, and the aluminized composite CDT (Refs 76,77 85) at higher dosages (3.82 x lO R) than OGK proplnt to provide further data on the extent of degradation. Gas evolved between 2.4-3.1 X 10 R causing blisters. At the max dosage marked deterioration occurred in the tensile strength, elongation, and work to produce max stress. By the Taliani test these materials had reached the end of their safe life... 

Likewise, density is not a useful measure of the detonability of a proplnt except perhaps to the extent that low density formulations may be porous. A more valid measure of the safe-life of proplnts is the depletion with time of stabilizers such as the nitroamines which are found in double base proplnts or the loss of the plasticizer. Such determinations can now be performed routinely in a quantitative fashion by means of liq chromatography Nuclear Radiation Hazard... 

Oxides and mixed catalysts Manufacturing of cement, concrete Refractory ceramics, a brick Faience and porcelain Safe life of medicines Terms and conditions of safe storage Recycling (processing) of products Formation and evolution of breeds (karsts) Evolution of the Solar System and the Universe Development of technologies for the production of materials for optoelectronics (GaN)... 

Composite materials have also been used to maintain and extend the safe life of bridges and reinforced concrete structures. Indeed, Australian, Japanese and US companies are already focusing on this technique. There are three principal ways in which composites can be used to rehabilitate ageing infrastructure ... 

The inspection provisions within the aircraft Maintenance Manual and associated Maintenance Requirements did not specify periodic visual inspections of such retainers, since they had been designed and certificated on a safe life basis... 

Safe life A system is designed according to the safe life principle if the safety relevant function is available with high probability. 

Here we will explain how the following principles have been implemented safe life, redundancy, diversity and others. 

We have demonstrated how to apply principles as safe-life, redimdancy, diversity and others. 

It is difficult to determine a relationship between the results of accelerated tests and of the natural exposure of certain durations. However, many attempts are published in which a safe life cycle is estimated from the results of accelerated tests. For example, it has been proposed that exposure of concrete elements to pure CO2 over a period of 36 days with a ratio of concentration 3000 times higher may give the same carbonation of concrete as 300 years of service in natural atmosphere (Levy 1992). In the tests carried out by Sisomphon and Franke (2007) it has been derived on the basis of the second Fick s law that the carbonation in natural exposure with concentration CO2 of 0.03% is approximately 10 times slower than in the accelerated tests at concentration CO2 of 3%. 

A safe life is not something that simply happens on its own. There is always something that needs to be done so that people feel that their environment, including their workplace, is safe—that they are not threatened by an accident, injury, or that the activities they carry out do not threaten or badly influence their health. To realize a safe life in a safe workplace and private environment means acquiring the principles of a safety culture and including them in all of one s actions. Occupational health and safety is embedded in the basic laws of economically developed countries. 

Understanding all of the relationships within risk management as a part of a culture of safety requires the active application of results from scientific and research projects, as well as their implementation in educational processes on all levels. Academic experts at various directing levels from any field of study (but mainly engineering, and the natural and social sciences) should acquire, master, and include the issues of safe life into their programs. 

A systematic project activity to ensure that a space payload intended for flight has sufficient structural integrity as to present no critical or catastrophic hazard. This activity also ensures quality of performance in the structural area for any payload. Central to the program is fracture control analysis, which includes the concepts of fail-safe and safe-life, defined as follows ... 

Safe-life— Ensures that the largest flaw that could remain undetected after nondestructive examination would not grow to failure during the mission. 

Design for a fixed life and plan to replace the part with a new one much like car manufacturers do with their maintenance schedules. This is sometimes called a so-called lifed part, finite lifetime concept [22], or safe-life design practice. 

Concept Todevelopalevelof understanding of the Equqnnent under Control (EUQ and its environment (pl ical. social, pcddical aiul legislative) suffident to enable dte other safely life cyde iurtivities to be satisfactorily performed. 

Using safe-life, fatigue and fracture mechanics principles to schedule preventative and/or corrective maintenance actions. 

Safe life The safe life design technique is employed in critical systems which are either very difficult to repair or may cause severe damage to life and property. These systems are designed to work for years without requirement of any repairs. 

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