History and Evolution of Control Banding: A Review

Abstract

Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents often encountered in the workplace. The original CB model was developed within the pharmaceutical industry; however, the modern movement involves models developed for non-experts to input hazard and exposure potential information for bulk chemical processes, receiving control advice as a result. The CB approach utilizes these models for the dissemination of qualitative and semi-quantitative risk assessment tools being developed to complement the traditional industrial hygiene model of air sampling and analysis. It is being applied and tested in small and medium size enterprises (SMEs) within developed countries and industrially developing countries; however, large enterprises (LEs) have also incorporated these strategies within chemical safety programs. Existing research of the components of the most available CB model, the Control of Substances Hazardous to Health (COSHH) Essentials, has shown that exposure bands do not always provide adequate margins of safety, that there is a high rate of under-control errors, that it works better with dusts than with vapors, that there is an inherent inaccuracy in estimating variability, and that when taken together the outcomes of this model may lead to potentially inappropriate workplace confidence in chemical exposure reduction in some operations. Alternatively, large-scale comparisons of industry exposure data to this CB model's outcomes have indicated more promising results with a high correlation seen internationally. With the accuracy of the toxicological ratings and hazard band classification currently in question, their proper reevaluation will be of great benefit to the reliability of existing and future CB models. The need for a more complete analysis of CB model components and, most importantly, a more comprehensive prospective research process remains and will be important in understanding implications of the model's overall effectiveness. Since the CB approach is now being used worldwide with an even broader implementation in progress, further research toward understanding its strengths and weaknesses will assist in its further refinement and confidence in its ongoing utility.

Evaluating the Control Banding Nanotool: a qualitative risk assessment method for controlling nanoparticle exposures

“…In a series of papers in 1998, the instrument was published (Annals 1998). International CB workshops and activities further refined the instrument, and explored possibilities to apply the control banding approach to other domains, such as ergonomics, occupational safety, and recently to control nanoparticle exposure (Zalk 2001;Annals 2003;Swuste 2007;AIHA 2007;Zalk and Nelson 2008;Paik et al 2008). Although CB has received criticism (see for instance Kromhout 2002;Swuste et al 2003;Jones and Nicas 2006;ACGIH 2008), the focus on controls is a strong point of the instrument and makes it applicable for operations with many uncertainties in hazard, exposure, and consequence data (ACGIH 2008).…”

“…Once a decision was made to build a qualitative approach, it was also easy to decide on using the 4 9 4 risk model that is utilized in many of the CB strategies. The 4 9 4 risk matrix has been found over time to balance ease-of-use with an appropriate level of rigor to develop a binning of established and graded control approaches in a historically acceptable manner (Maidment 1998;ANSI 2000;Zalk and Nelson 2008). The research also presented a relatively consistent set of factors that should be used in the model, of which each is needed to be included in the scheme for scoring input; however, the weighting of each factor relative to the others was a bit more involved and required a relative risk approach in line with the available research (Robichaud et al 2005).…”

Comparison and Evaluation of Multiple Users’ Usage of the Exposure and Risk Tool: Stoffenmanager 5.1

“…(Zalk and Nelson 2008). Under this programme a tool was developed that takes into account both hazards and potential exposures.…”

“…As in COSHH essentials, the hazard classification in Stoffenmanager is based principally on available risk phrases, but its exposure assessment is more advanced and based on an algorithm by Cherrie et al (1996) and Cherrie and Schneider (1999). As the number of chemicals increased faster than occupational exposure limits (OELs) could be established to assess their risks, the need for control banding tools also increased (Zalk and Nelson, 2008). A control banding tool that prioritises risk is especially useful for small and medium-sized enterprises that do not have the resources to consult an expert in chemical risk assessment.…”

“…Models such as the Stoffenmanager's quantitative part may also be used to estimate and predict exposures in compliance with the REACH legislation, in which modelled exposures are compared with DNEL (derived no effect level) levels for safe use (ECHA 2012). Because one purpose of such tool is to select the right level of control, and under-prescription of control can lead to serious injury, the tools over-predict the exposure to ensure the security of the outcomes (Zalk and Nelson 2008). Hence, the models are conservative.…”