Évaluation d’indices de comparaison pour la substitution des solvants en milieu de travail

La substitution est une méthode de prévention primaire qui permet l’élimination à la source des dangers pour les travailleurs. Une des étapes de la démarche est la comparaison des options afin de procéder au choix final. Divers indices de comparaison, basés sur des paramètres physicochimiques, sanitaires et environnementaux des substances, permettent de guider ce choix. Toutefois, aucune évaluation de ces indices n’a été effectuée dans le cas de la substitution des solvants. Une recherche de développement a été entreprise afin de proposer une méthodologie améliorée de comparaison des solvants. La démarche d’analyse de substitution et la comparaison des options de remplacement à l’aide du rapport de danger de vapeur (« Vapour Hazard Ratio », VHR) ont été appliquées à un cas réel de substitution de solvants en entreprise. Trois indices de potentiel de surexposition (IPS) (VHR, « Måleteknisk Arbejdshygiejnisk Luftbehov » (MAL) et « SUBstitution FACtor » (SUBFAC)) et trois indices globaux de hiérarchisation des dangers (indice air (ψiair), « Indiana Relative Chemical Hazard Score » (IRCHS) et « Final Hazard Score » (FHS)) ont été évalués et comparés à partir de listes de 56 et 67 solvants respectivement. La problématique de la non-idéalité des mélanges a aussi été considérée par rapport aux IPS par l’évaluation et la comparaison de 50 mélanges de solvant. Une méthodologie d’établissement d’une valeur limite d’exposition (VLE), pour les solvants n’en possédant pas, a été développée par modélisation de type relations quantitatives propriété-propriété (QPPR). La modélisation QPPR des VLE, effectuée sur une liste de 88 solvants possédant une VLE, a été effectuée à partir des coefficients de partage octanol:air, octanol:eau, sang:air et des constantes métaboliques. L’étude de cas a montré que l’utilisation du VHR facilitait la comparaison des options, bien qu’elle puisse se heurter à l’absence de VLE. Les indices VHR et SUBFAC ont été identifiés comme des méthodes très proches, caractérisées par une forte corrélation (R=0,99) alors que l’indice MAL se distingue des deux autres IPS par une perte d’information sur la volatilité résultant en une corrélation plus faible avec le VHR (R=0,75). L’impact de la non idealité, évalué par le calcul de coefficients d’activité sur une série de 50 mélanges, a permis d’établir que les ratios entre les indices VHR corrigés et non corrigés variaient entre 0,57 et 2,7, suggérant un facteur de sécurité de cinq lors de la comparaison de mélanges. Les analyses de corrélation et de sensibilité ont montré que les indices de hiérarchisation des dangers différaient de façon importante sur leur prise en compte de paramètres comme la volatilité, les VLE, l’exposition cutanée, l’inflammabilité, la cancérogénicité et les divers paramètres environnementaux. Aucun de ces indices ne peut être recommandé pour la substitution des solvants. Deux modèles QPPR ont été développés afin de prédire des VLE et des VHR, et 61 % et 87 % des VHR prédits variaient respectivement d’un facteur maximal de deux et de cinq par rapport aux VHR calculés. Nos résultats mènent à proposer une démarche améliorée de comparaison en deux étapes. Après un tri selon des critères prioritaires de santé, de sécurité et d’environnement, la comparaison devrait se baser sur le calcul du VHR tout en considérant d’autres paramètres selon la situation concrète de l’entreprise ou du procédé. La comparaison devra tenir compte de la non-idéalité pour les mélanges, et de VLE estimées pour les solvants n’en possédant pas.

German open ended funds: was there a valuation problem?

In late 2005, a number of German open ended funds suffered significant withdrawals by unit holders. The crisis was precipitated by a long term bear market in German property investment and the fact that these funds offered short term liquidity to unit holders but had low levels of liquidity in the fund. A more controversial suggestion was that the crisis was exacerbated by a perception that the valuations of the fund were too infrequent and inaccurate. As units are priced by reference to these valuations with no secondary market, the valuation process is central to the process. There is no direct evidence that these funds were over-valued but there is circumstantial evidence and this paper examines the indirect evidence of the process to see whether the hypothesis that valuation is an issue for the German funds holds any credibility. It also discusses whether there is a wider issue for other funds of this nature or whether it is a parochial problem confined to Germany. The conclusions are that there is reason to believe that German valuation processes make over-valuation in a recession more likely than in other countries and that more direct research into the German valuation system is required to identify the issues which need to be addressed to make the valuation system more trusted.

The uncertainty of valuation

Valuation is often said to be “an art not a science” but this relates to the techniques employed to calculate value not to the underlying concept itself. Valuation is the process of estimating price in the market place. Yet, such an estimation will be affected by uncertainties. Uncertainty in the comparable information available; uncertainty in the current and future market conditions and uncertainty in the specific inputs for the subject property. These input uncertainties will translate into an uncertainty with the output figure, the valuation. The degree of the uncertainties will vary according to the level of market activity; the more active a market, the more credence will be given to the input information. In the UK at the moment the Royal Institution of Chartered Surveyors (RICS) is considering ways in which the uncertainty of the output figure, the valuation, can be conveyed to the use of the valuation, but as yet no definitive view has been taken apart from a single Guidance Note (GN5, RICS 2003) stressing the importance of recognising uncertainty in valuation but not proffering any particular solution. One of the major problems is that Valuation models (in the UK) are based upon comparable information and rely upon single inputs. They are not probability based, yet uncertainty is probability driven. In this paper, we discuss the issues underlying uncertainty in valuations and suggest a probability-based model (using Crystal Ball) to address the shortcomings of the current model.

Valuation accuracy: reconciling the timing of the valuation and sale

Carsberg (2002) suggested that the periodic valuation accuracy studies undertaken by, amongst others, IPD/Drivers Jonas (2003) should be undertaken every year and be sponsored by the RICS, which acts as the self-regulating body for valuations in the UK. This paper does not address the wider issues concerning the nature of properties which are sold and whether the sale prices are influenced by prior valuations, but considers solely the technical issues concerning the timing of the valuation and sales data. This study uses valuations and sales data from the Investment Property Databank UK Monthly Index to attempt to identify the date that sale data is divulged to valuers. This information will inform accuracy studies that use a cut-off date as to the closeness of valuations to sales completion date as a yardstick for excluding data from the analysis. It will also, assuming valuers are informed quickly of any agreed sales, help to determine the actual sale agreed date rather than the completion date, which includes a period of due diligence between when the sale is agreed and its completion. Valuations should be updated to this date, rather than the formal completion date, if a reliable measure of valuation accuracy is to be determined. An accuracy study is then undertaken using a variety of updating periods and the differences between the results are examined. The paper concludes that the sale only becomes known to valuers in the month prior to the sale taking place and that this assumes either that sales due diligence procedures are shortening or valuers are not told quickly of agreed sale prices. Studies that adopt a four-month cut-off date for any valuations compared to sales completion dates are over cautious, and this could be reduced to two months without compromising the data.

Influences on secured lending property valuations in the UK

A significant part of bank lending in the UK is secured on commercial property and valuations play an important part in this process. They are an integral part of risk management within the banking sector. It is therefore important that valuations are independent and objective and are used properly to ensure that secured lending is soundly based from the perspective of both lender and borrower. The purpose of this research is to examine objectivity and transparency in the valuation process for bank lending and to identify any influences which may undermine the process. A detailed analysis of 31 valuation negligence cases has been followed by two focus groups of lenders and valuers and also questionnaire surveys of commercial lenders and valuers. Many stakeholders exist, for example lenders, borrowers and brokers, who are able to influence the process in various ways. The strongest evidence of overt influence in the process comes from the method of valuer selection with borrowers and brokers seen to be heavily involved. There is some also some evidence of influence during the draft valuation process. A significant minority of valuers feel that inappropriate pressure is applied by borrowers and brokers yet there is no apparent part of the process that leads to this. The panel system employed by lenders is found to be a significant part of the system and merits further examination. The pressure felt by valuers needs more investigation along with the question of if and how the process could dispel such feelings. This is seen as particularly important in the context of bank regulation.

Benchmarking and valuation issues in measuring depreciation for European office markets

Purpose – The paper addresses the practical problems which emerge when attempting to apply longitudinal approaches to the assessment of property depreciation using valuation-based data. These problems relate to inconsistent valuation regimes and the difficulties in finding appropriate benchmarks. Design/methodology/approach – The paper adopts a case study of seven major office locations around Europe and attempts to determine ten-year rental value depreciation rates based on a longitudinal approach using IPD, CBRE and BNP Paribas datasets. Findings – The depreciation rates range from a 5 per cent PA depreciation rate in Frankfurt to a 2 per cent appreciation rate in Stockholm. The results are discussed in the context of the difficulties in applying this method with inconsistent data. Research limitations/implications – The paper has methodological implications for measuring property investment depreciation and provides an example of the problems in adopting theoretically sound approaches with inconsistent information. Practical implications – Valuations play an important role in performance measurement and cross border investment decision making and, therefore, knowledge of inconsistency of valuation practice aids decision making and informs any application of valuation-based data in the attainment of depreciation rates. Originality/value – The paper provides new insights into the use of property market valuation data in a cross-border context, insights that previously had been anecdotal and unproven in nature.

Influences on secured lending property valuations in the UK

A significant part of bank lending in the UK is secured on commercial property and valuations play an important part in this process. They are an integral part of risk management within the banking sector. It is therefore important that valuations are independent and objective and are used properly to ensure that secured lending is soundly based from the perspective of both lender and borrower. The purpose of this research is to examine objectivity and transparency in the valuation process for bank lending and to identify any influences which may undermine the process. A detailed analysis of 31 valuation negligence cases has been followed by two focus groups of lenders and valuers and also questionnaire surveys of commercial lenders and valuers. Many stakeholders exist, for example lenders, borrowers and brokers, who are able to influence the process in various ways. The strongest evidence of overt influence in the process comes from the method of valuer selection with borrowers and brokers seen to be heavily involved. There is some also some evidence of influence during the draft valuation process. A significant minority of valuers feel that inappropriate pressure is applied by borrowers and brokers yet there is no apparent part of the process that leads to this. The panel system employed by lenders is found to be a significant part of the system and merits further examination. The pressure felt by valuers needs more investigation along with the question of if and how the process could dispel such feelings. This is seen as particularly important in the context of bank regulation.

A question of value: a discussion of property pricing and definitions of value

Valuation is often said to be “an art not a science” but this relates to the techniques employed to calculate value not to the underlying concept itself. Valuation practice has documented different bases of value or definitions of value both internationally and nationally. This paper discusses these definitions and suggests that there is a common thread that ties the definitions together.

Commercial property loan valuations in the UK : the changing landscape of practice and liability

This paper is the first of two which aim to examine the major legal liability implications of changes to the commercial property loan valuation process caused by the recession in the UK property market and to make recommendations to valuers and their professional institutions to improve the quality of the process and the result. This paper identifies the market background to commercial property lending and discusses the implications of the falls in value for lenders and valuers. These include two major strands; first, the outcome of discussions between the representative bodies of these two groups and, second, the increasing litigation caused by lenders suing valuers for professional negligence. The discussions between representative groups have driven a debate on the valuation process leading to a number of reports and guidance notes. This paper discusses the outcomes paying particular attention to the basis of valuation for loan purposes and the provision of additional information in valuation reports. This paper also reviews the legal framework which influences the relationship between the lenders and valuers and discusses the duty of care. The role of instructions in the valuation process, the significance of the identity of the person to be advised and the possibility of a conflict of interest arising are all considered. The paper also addresses the issue of the standards required of a commercial loan valuer, including how this is interpreted by the courts and the legal status of professional guidance notes. The paper concludes by identifying potential areas for dispute within the loan valuation process and raising a number of research questions concerning the operation of this process which are addressed in a following paper.

Commercial property loan valuations in the UK : implications of current trends in practice and liability

This paper is the second of two papers which aim to examine the major legal liability implications of changes to the commercial property loan valuation process caused by the recession in the UK property market and to make recommendations to valuers and their professional institutions to improve the quality of the process and the result. The objectives of this paper are to address a number of the practical implications of changes to the loan valuation process within the context of legal liability. The results of an interview survey of lenders and valuers are reported and analysed. The survey examined the loan valuation process including the selection and instruction of valuers, bases of valuation and valuation reporting. In the selection and instruction process, the findings of the survey reveal two potential problems within the valuer/lender relationship. First, valuers still occasionally accept instructions from borrowers and this could lead to a conflict of interest as lenders may rely on the survey. Second, the occasional lack of formal instructions prior to the delivery of reports casts doubt on the valuer’s ability to correctly identify the needs of clients. Regarding the basis of valuation, it was found that valuers are providing valuations on bases which they do not think are appropriate. Valuers may be legally liable if they do not inform clients of their reservations and this situation must be urgently addressed. The survey also confirms previous research that valuation reports are considered to be light on contextual information concerning markets. The paper concludes by making a number of specific recommendations concerning possible improvements to the commercial property loan valuation process.

Valuation and arbitrage

The use of discounted cash flow (DCF) methods in investment valuation and appraisal is argued by many academics as being rational and more rigorous than the traditional capitalisation model. However those advocates of DCF should be cautious in their claims for rationality. The various DCF models all rely upon an all-encompassing equated yield (IRR) within the calculation. This paper will argue that this is a simplification of the risk perception which the investor places on the income profile from property. In determining the long term capital value of a property an 'average' DCF method will produce the 'correct' price, however, the individual short term values of each cash-flow may differ significantly. In the UK property market today, where we are facing a period in which prices are not expected to rise generally at the same rate or with such persistence as hitherto, investors and tenants are increasingly concerned with the down side implications of rental growth and investors may indeed be interested in trading property over a shorter investment horizon than they had originally planned. The purpose of this paper is therefore to bring to the analysis a rigorous framework which can be used to analyse the constituent cash flows within the freehold valuation. We show that the arbitrage analysis lends itself to segregating the capital value of the cash flows in a way which is more appropriate for financial investors