Check List Method

The check list method is based on past experience. The process description, the operating mode, is screened using a list of possible failures or deviations from this particular operating mode. Thus, it is obvious that the quality and comprehensiveness of the check list directly govern its efficiency. Indeed, the experience of the authors confirms that the check list is essential. This method is well adapted to discontinuous processes as practised in the fine chemicals and pharmaceutical industries, where processes are often performed in multi-purpose plants. The basic document for the hazard identification is the process description, also called operating mode. Each step of the process is analysed with the check list. 

Question May a deviation from these conditions lead to a hazard  

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The hazard identification methods presented in Sections 1.5.1 to 1.5.6 above are all based on strongly systematic procedures. In the check list method, the systematic is provided by the check list itself. The comprehensiveness can be verified in the matrix (see Figures 1.4 and 1.5). With the FMEA, the systematic is provided by the division of the system into elements and the failure modes considered. In the HAZOP study, the systematic stems from the division of the plant into nodes and lines, then the systematic application of the keywords. With the decision table method, the systematic is inherent to the table. For the FTA and ETA, the systematic is given by the tree and the logical ports. Nevertheless, the work of the team must be traceable, even by persons who did not participate to the analysis. Thus, it is recommended to also document the hazards that were not considered as critical. 

What-ll/Checklist combines the creative, brainstorming features of a What-lf with the systematic features of a Checklist. The What-lf analysis considers accidents beyond the checklist the check list lends a systematic structure to the What-lf analysis. A What-lf7Checklist examines the potential consequences of accident scenarios at a more general level than some of the more detailed I l liA methods. It can be used for any type of process at any life cycle stage. 

Methods for the calculation of pressure drop through pipes and fittings are given in Section 5.4.2 and Volume 1, Chapter 3. It is important that a proper analysis is made of the system and the use of a calculation form (work sheet) to standardize pump-head calculations is recommended. A standard calculation form ensures that a systematic method of calculation is used, and provides a check list to ensure that all the usual factors have been considered. It is also a permanent record of the calculation. Example 5.8 has been set out to illustrate the use of a typical calculation form. The calculation should include a check on the net positive suction head (NPSH) available see section 5.4.3. 

Inductive methods, such as check lists, Failure Mode and Effect Analysis (FMEA), event trees, decision tables, Analysis of Potential Problems (APP). These methods proceed from an initial cause of the deviation and construct a scenario ending with the final event. They are based on questions of the type What if ... 

Visual inspection is a classical example of quality by attributes , where the batch is compared with a standard , which can be a quality perfect example of the component or a quality check list. It should be noted that the physical senses of smell and taste, where safe, are often more sensitive than many sophisticated analytical methods, but equally require validation and standardisation. 

A proper selection of materials depends on sufficient knowledge on how the actual practical conditions affect each material eandidate. To ensure that important aspects are not forgotten, check lists should be used, which should include risk of different forms of eorrosion for each candidate, relevant conditions affecting each form of corrosion, possibilities of changing the eorrosion properties of a certain material, possibilities for application of various protection methods, accessibility for maintenanee, environmental conditions, loads and special requirements during various parts of the lifetime etc. Aspects related to other functional properties than the eorrosion properties should of eourse be treated in similar ways. 

A methodical examination of a process, plant and procedure which identifies hazards, assesses risks and proposes measures which will reduce risks to an acceptable level. (May use inter alia Hazops. Fault Tree Analysis, Check-lists, Event Tree Analysis. FMECA, etc). 

Index methods are based on structured check lists, which translate definitions in numeric values. Final indexes - which represent risk levels - derive from numerical combinations of the values, according to empirical algorithms. The first safety index method was the DOW Fire and Explosion Index (AIChE 2005), which was proposed in the seventies. Hazard sources and safety barriers are accounted respectively as Penalties and Credits. 

Any good quality-assurance system should also assess the quality of performance in practice as well as in theory. With no currently available, effective, non-destructive test, critical areas or components may only be assessed for voids (acoustic methods are useful here) and, where possible, proof loaded. Other than this, test coupons or parts need to accompany the components themselves through the assembly process so that appropriate, systematic destructive tests may be carried out. A check-list for safety critical items is given in Table 6.1. 

Methods, procedures, and check lists for process operations with nuclear hazard potential eu e prepcured to ensure that execution of maintenance work, process functions, inspections, functional tests of critical equipment, reactor startup preparations, and reactor operations are conducted In accordance with Process Standards and Equipment Maintenance Standards. Special operating and maintenance procedures are provided for in-reactor test facilities. 

The individual who uses a tight-fitting respirator is to perform a user seal check to ensure that an adequate seal is achieved each time the respirator is put on. Either the positive and negative pressure checks listed in this appendix, or the respirator manufacturer s recommended user seal check method shall be used. User seal checks are not substitutes for qualitative or quantitative fit tests. 

Table 8 Check list for the selection of method/technique of application and curing...

If one plans to purchase an automatic method development system, one will first have to get an idea of the systems that are presently available on the market Essentially, only ChromSword Auto and, since recently, AMDS (based upon DryLab) are available, along with H EUREKA, which is presently being established on the market Characteristics and experiences with the three systems are compared in Table 2. This table can also be used as a check list in order to facilitate the decision in favor of one system or the other. 

Check-hsts are a generic method that can be apphed in many fields within urban security. Particularly advantageous is that expert knowledge and knowledge from past experiences can be processed this way so that these check-lists can be used with relatively httle experience and knowledge. 

MEHARI2010 (Method for Harmonized Analysis of Risk) (MEHARI 2010) is a (rare) IT RA check list based approach following these steps, basing on (Stonebumer et al. 2002), and the Code of Practice in IT security (ISO/IEC-27002 2005). 

ABSTRACT Statistics on traffic accidents annually contain a number of serious accidents involving the hazardous substances on roads and railways, which are accompanied by explosions, fires, leaks of hazardous substances into the environment, or a combination of the two to three mentioned phenomena which have impacts on the protected assets in a traffic accident site, and perhaps as a consequence of internal links and couplings they seriously damage the environment surrounding the accident site. By application of empirical data and procedures of risk engineering it was compiled the check list by which it is possible to determine the critical sites on roads and railways in advance, and it was tested specifically aimed What, If the method, by which it is possible to determine in advance scenarios of impacts of traffic accidents involving the hazardous substances and to determine critical aspects of critical sites from the viewpoint of protection of humans and other public assets. 

The stresses in joints are discussed extensively so that the engineer can get sufficient philosophy or feel for them, or can delve more deeply into the mathematics to obtain quantitative solutions even with elasto-plastic behaviour. A critical description is given of standard methods of testing adhesives, both destructively and non-destructively. The essential chemistry of adhesives and the importance of surface preparation are described and guidance is given for adhesive selection by means of check lists. For many applications, there will not be a unique adhesive which alone is suitable, and factors such as cost, convenience, production considerations or familiarity may be decisive. A list of applications is given as examples. 

Another method of eliminating collision checks was proposed but not implemented in this initial collision prediction system elimination by the dynamic position of objects in the environment. Some objects can move in and out of range of other objects. For example, a space manipulator on a moving platform may move from one position on the Space Station, where it must avoid certain antennae, to another position where the antennae are out of reach, but the solar arrays are now a concern. In dynamic collision elimination, objects in the antennae cluster would be removed from the collision-check list of the manipulator, while the solar array objects would be added. Using this approach, major sections of the geometric database could be removed from consideration, greatly reducing the required calculations at each cycle. 

In particular, the known stress calibration method was chosen, therefore 6 rosetta strain gauges (R1-R6) on the shell and 7 (R7-R13) on the the head were applied. Their distances measured from the head centre are listed in table 1. R3 and R4 were applied only to check a uniform stress level on the shell surface. 

The relative merits of various MO methods have been discussed in die literature. In general, the ab initio type of calculations will be more reliable, but the semiempirical calculations are faster in terms of computer time. The complexity of calculation also increases rapidly as the number of atoms in the molecule increases. The choice of a method is normally made on the basis of evidence that the method is adequate for the problem at hand and the availability of appropriate computer programs and equipment. Results should be subjected to critical evaluation by comparison widi experimental data or checked by representative calculations using higher-level mediods. Table 1.12 lists some reported deviations from experimental AHf for some small hydrocarbons. The extent of deviation gives an indication of the accuracy of the various types of MO calculations in this application. 

To illustrate this with a few cases to demonstrate the possibilities and iimits of this method, chemicais wiil be chosen for which there are numerous vaiues of LC and/or LD50 avaiiabie to be abie to check the quality of the estimates. For each of these the values that are listed in the safety data in Part Three will be given. 

Much of the early work with certified reference materials was linked to the derivation of reference methods and there was a period in which primary or definitive (i.e. very accurate but usually very complex) and secondary (or usable) methods were reported e.g. steroid hormones (Siekmann 1979), creatinine (Siekmann 1985), urea (Welch et al. 1984) and nickel (Brown et al. 1981). Although there are some application areas, such as checking the concentrations of preparations listed in a pharmacopoeia, where a prescribed, defined method has to be used, in practice such work is limited. However, this approach to chemical analysis is no longer widely used and will not be further discussed. The emphasis now is placed on using RMs to demonstrate that a method in use meets analytical criteria or targets deemed to be appropriate for the application and to develop figures of merit (Delves 1984). 

The list will probably contain a mixture of processes that lead to values of the performance parameters and quality control checks. A more structured approach will now be taken to method validation. The important performance characteristics are shown in Table 4.6. 

It has been stated that the method using HPLC as an analytical tool can be applied for the study of the adsorption of dyes, furthermore, it can be employed for the optimization of adsorption efficacy in environmental protection studies [146], New precursors for cyanine dyes were synthesized and the purity of the end products was checked by RP-HPLC. The chemical structures and UIPAC names of the intermediates are listed in Fig. 3.84. Purity control and the identification of the intermediates was performed in an ODS column... 

O Design a titration that uses an iodine solution to determine and compare the concentration of vitamin C in a variety of fresh fruit juices. You may find it helpful to research appropriate procedures on the Internet. Include a method for standardizing the iodine solution. (See Challenge question 1.) Make sure that you list all the safety precautions you will use in your titration. Check your procedure with your teacher, and then carry out your titration. 

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