Sir; Although RedPrairie has not been involved in Asda's implementation of voice-picking technology, we would like to point out there is absolutely no need for voice technology to create unsafe working conditions for retail and warehouse staff ('Pick rate report to put strain on Asda', The Grocer, 13 January, p12).

Safety risks are mitigated by establishing best practice processes. In a picking environment, the various influences on work rate must be taken into account, for example the weight and shape of different items, the height of pick-faces, the distances between them, the nature of equipment required, etc. With this knowledge, safe, efficient and realistic 'preferred methods' can be defined.

Care must also be taken to avoid worker resistance to what might be perceived as Big Brother-style surveillance. Measuring staff against standards is a fair and objective way to evaluate their performance, which tends to lift rather than damage morale. It also lays the groundwork for performance-related bonuses, which give an extra boost to productivity, and for a culture of continuous improvement.