Standards essential requirements

EC Design-examination Certification Certification based on examination of the design dossier versus standards/essential requirements (paperwork review)... 

EC Type-examination Certification Certification of design based on testing of physical samples versus standards/essential requirements EC Verification Certification... 

Harmonised standards are technical specifications adopted by one of the European standards organisations following a mandate issued by the European Commission on which Member States were consulted. When published by the Commission in the Official Journal of the European Communities, the hamionised standards give presumption of confomiity to the essential requirements they specify. This means that manufacturers applying these standards do not have to demonstrate the compliance of the manufactured products with the relevant requirements of the directive. 

Calibration. Cahbration of lab instmments is important to the accuracy of test results. CaUbration, the use of an accepted standard to adjust an instmment or measurement standard so as to improve the accuracy of the instmment or measurement, is an essential requirement of both the U.S. Food and Dmg Administration (FDA) Good Manufacturing Practice (GMP) (24) and the ISO 9000 standards (25). 

Figure 19.8 shows the design of an all-glass cell, which has been listed as the standard polarisation cell in the ASTM Recommended Practice G5 1987, which makes provision for the essential requirements listed above this cell is typical of those used for fundamental studies and for testing, although details of design may vary. 

Although the directives allow flexibility in the methods and solutions that a manufacturer may employ to fulfil the essential requirements, they promote the use of standards as the preferred method to establish conformity. Specifically, the directives stipulate that Member States shall presume compliance with the essential requirements in respect of devices that are in conformity with relevant harmonised standards. 

The European Commission has mandated CEN/CENELEC to develop many standards to support manufacturers in the realisation of the essential requirements of the Directives. If the Commission determines that an adopted standard is fit for this purpose, then a reference is published in the Official Journal of the EU, which elevates the status of the standard to that of a harmonised standard for European regulatory purposes. 

The Commission provides a list of over 230 standards that may be used to establish conformance with the essential requirements of the medical device directives. 

The results of the risk analysis and a list of harmonised standards applied in full or in part, and descriptions of the solutions adopted to meet the essential requirements of this Directive if the harmonised standards have not been applied... 

Where there is a dosing device provided with the product, the dose reproducibility and accuracy should be demonstrated. Examples include dropper devices, dose-measuring devices, and pen injectors. The instructions for use should also be discussed for such devices and may be particularly important for devices such as two-chamber cartridges and the like containing suspension products. It might be necessary to discuss how dosing devices meet the relevant Essential Requirements of the Medical Device Directives with reference to appropriate and relevant harmonized and other European (EN) and International Standards Organization (ISO) standards. 

As we have seen that the volumetric analysis essentially requires the precise and accurate measurement of weights and volumes of interacting solutions. However, the weights are measured upto the fourth place of decimal by using a manually operated good analytical balance or a single-pan electrical balance that need to be calibrated periodically with the help of a standard weight box. 

RIA for hydromorphone and hydrocodone are fairly sensitive in the nanogram per millilitre range but essentially require the preparation of a specific antibody. The laid-out RIA method is quite capable of estimating the above drugs within a range of 2.5-20 ng ml 1 using standard 100 pi plasma sample only. 

A manufacturer must apply an appropriate conformity assessment procedure to their device in order to ensure that it complies with the essential requirements, after which they must certify this fact by completing a declaration of conformity. There is usually a choice of conformity assessment procedures open to a manufacturer, depending on a risk-based classification of the class into which the device falls. The two main approaches to conformity assessment are based either on an approved total quality management system audited to ISO 9000 series standard, as customised for medical devices with EN 46 000 series standard, or individual product assessment. 

European Communities are presumed by Member States to comply with those aspects of the essential requirements that are covered by the standard. Harmonised standards are those adopted by the EC standards bodies pursuant to a mandate issued by the Commission, in this case the European Committee for Standardisation (CEN) and the European Committee for Electrotechnical Standardisation (CENELEC). A large number of standards are contemplated but may take time to be written and adopted. Standards may be horizontal (covering aspects common to all or a number of product types) or vertical (dealing only with a specific aspect or specific product type). Important harmonised standards exist on the following ... 

The essential requirements contained in Aimex I of each new approach Directive specify the aspects of safety and performance that must be satisfied at the time at which a relevant product is placed on the market. Essential requirements are stated as principles or as generalised aspects and exclude detailed technical requirements. The scheme of the Community s new approach is that detailed technical aspects are not required as legal obligations but, if they are generally accepted, may be applied voluntarily by manufacturers through being included in official standards. The essential requirements are intended to be comprehensive and all must be satisfied save for those requirements that do not apply to a particular product as a matter of common sense. 

Since 1998, all medical devices marketed in Europe (EEA) must bear the CE mark, which signifies conformity to the essential requirements of the MDD. The MDD harmonized the European requirements along with device certification and the inspection procedures for manufacturers to ensure the highest degree of safety and product quality of the medical devices throughout the EC. Most important was the requirement for a full quality assurance system (Annex II of the MDD, 93/42/EEC), which included design controls for new medical device products. This was in line with the ISO 9000 series of standards established for quality systems by the International Organization for Standardization. 

The Consultative Committee for Amount of Substance (CCQM) has set up a definition of primary methods [1, 2] and has selected some methods with the potential of being primary , from the viewpoint of the end user. From the point of view of metrology, methods used for linking the chemical measurements with the SI system at the highest level should not refer to other amount of substance standards. This requirement excludes methods which are relative in their principle. Some other methods identified as having the potential to be primary yield information expressed as amount fraction. This is essential for evaluation of purity, but in order to convert it to a value useful for transfer of the unit, additional information on the identity (molar mass) and content of the impurities is required. This additional information is needed to convert the result into amount content or similar quantities. 

Preservation of acceptable levels of power quality is an essential requirement for the operation of power systems, APS included. Frequency stability and voltage control are the most important aspects of this issue. The European Standard EN-50160 (European Standard EN-50160, 1994) requires that for a non-interconnected (i.e. autonomous) power system, frequency and voltage should be within a range of ... 

To account for absorption effects, an additional measurement is required. With the internal standard method, the profile for the internal standard must be measured for both calibration standards and samples. The rather small quantity of analyte present in the sample requires the addition of a similar quantity of internal standard (a, 200 ug) necessitating the measurement of the standards profile under essentially the same conditions as that of the analyte. Consequently, the internal standard method requires an additional measurement time approximately equal to that of the analyte. Under conditions noted above, this would amount to approximately thirty minutes total analysis time per sample. 

Before considering individual types of electrical apparatus, flameproof joints as an essential element of d shall be dealt with. The contents of EN 50018 and IEC 60079-1 are different, depending on the edition of the standard. The requirements are listed in Tables 6.27, 6.28 and 6.29. The values given in these tables are constructional requirements and ensure the flameproofness of an enclosure except for extreme shapes, e.g. long U-shaped pipes for electric heaters. In such cases, the gap shall be reduced to an appropriate value. 

The time required for the preparation of the standards essentially depends on the number of elements introduced into each standard. By way of example, a calibration range comprising ten analytical elements requires at least 4 hours preparation. Moreover, these solutions only have a limited conservation time which is shortened if the element concentration levels are low (a few mg/1 or less). 

---