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The aim of the project was to find and compile information on human responses to contact with cold surfaces. The work has covered 1) literature search and field survey; 2) experimental studies with human subjects; 3) simulation by modeling; 4) instrumentation (artificial finger), 5) establishment of database and 6) proposal of a draft standard for cold touchable surfaces. The field survey in food processing industries has showed that the cold hazards in hands, especially fingers, often occur. The experimental results with human subjects indicate a more rapid reduction in contact temperature when finger/hand contact metallic surfaces compared to non-metallic surfaces, such as stone, nylon and wood. The temperature drop was found to be function of skin and material surface temperature, material and skin properties and contact conditions (pressure, area). Manual performance (tactile sensitivity/finger dexterity) decreased after gripping cold rods. The safety criteria for contact temperature are suggested to be 0 °C for freezing cold injury, 7 °C for numbness and 15 °C for pain sensation. The time to reach these criteria when touching or gripping cold objects of different material has been determined and compiled in a database. An analytical, mathematical model was derived and an artificial finger was developed to derive additional cooling information for very cold conditions under which no human experiments could be performed. The results of the project have been issued in a document that can serve as a basis for the development of an ergonomics database by appropriate standardisation bodies (TC122/WG3). The standard is applicable for all fields where cold surfaces cause a risk of hand/finger contact cooling. Summary 2 Contents 3 Definitions 5 Touchable surfaces 5 Surface temperature (Ts, °C) 5 Initial hand/finger skin temperature (Tsk,h0/Tsk,f0), °C) 5 Contact temperature (Tc, °C) 5 Contact duration (D, sec.) 5 Thermal inertia of a material 5 Contact factor (Fc, Jm^{-2}s^{-1/2}K^{-1}) 5 Time for Tc to reach criteria 5 Introduction 6 Roles of the different partners 7 1. National Institute for Working Life (NIWL) 7 2. Loughborough University (LUUK) 7 3. Human Factors Research Institute (TNO-HFRI) 7 4. Finnish Institute of Occupational Health (FIOH) 8 5. Louvain Catholic University (HYTR-UCL) 8 All the work carried out 8 Work package 1 - Literature review and field survey 8 1 Literature review 8 2 Field survey 8 2.1 Questionnaire study 9 2.2 Temperature measurements 9 Work package 2 - research 9 1 Objectives 9 2 Materials and methods 9 2.1 Selection and test of the materials 9 2.2 Experimental protocol 10 2.3 Sticking experiments 12 2.4 Data management 12 Work package 3 - Modelling 13 1 Objectives 13 2 Methods 13 2.1 Overview the models of extremity cooling 13 2.2 Adapt the existing models of extremity cooling 13 Work package 4 - Development of instrumentation 15 1 Objectives 15 2 Experimental work 15 2.1 Initial work with manufacturer 15 2.2 More experiments of the prototype of artificial finger 16 Work package 5-Compilation of database 16 1 Objectives 16 2 Methods 17 2.1 Protocol of the database 17 2.2 Management of the database 17 Work package 6 - Draft proposal for guideline document 17 1 Objective 17 2 Method 17 Results 18 1. Literature review and filed study 18 1.1 Literature review 18 1.1.1 Properties of the human hand 18 1.1.2 Human responses during contact cooling 18 1.1.3 Thermal conductance in peripheral tissues 18 1.1.4 Contact cooling in the industry 19 1.1.5 Models of extremity cooling 19 1.1.6 Assessment of contact cooling 19 1.2 Field study 20 1.2.1 Questionnaire and interview 20 1.2.2 Temperature measurements 22 2 Experimental research 23 2.1 Finger touching experiments 23 2.1.1 Effect of parameter on response of contact temperature with duration 23 2.1.2 Subjective response on thermal and pain sensations 27 2.1.3 Contact time of finger touch on cold surfaces for the critical Tc (15,7 and 0 °C) 28 2.2 Gripping experiments 29 2.2.1 Statistical analysis hand cooling in gripping 29 2.2.2 Individual variation during gripping cold surfaces 29 2.2.3 Duration of gripping cold surfaces 29 2.2.4 Effect of hand gripping cooling on manual performance 30 2.3 Results of sticking experiments 31 2.3.1 Sticking force by fingertip 31 2.3.2 Sticking force by covered hand gripping 32 3 Modelling 33 3.1 Modelling of fingertip contact cooling 33 3.2 Modelling of hand cooling during gripping 35 4 Prototype of instrumentation 36 4.1 Change in Tc of artificial finger contact metallic surfaces at temperature ≤-20 °C 36 4.2 Comparison of cooling curves between artificial and human fingers 36 5 Database 37 5.1 Results of database for finger touching experiments 37 5.2 Results of database for hand gripping experiments 38 5.3 Empirical relationship of contact time with penetration coefficient and surface temperature of the material 41 6 Draft proposal for guideline document 45 6.1 Threshold data 45 6.1.1 Freezing thresholds for finger contacting cold surfaces 45 6.1.2 Numbness thresholds for finger contact with cold surfaces 46 6.1.3 Pain thresholds 46 Conclusions 47 1 Field and literature study 47 2 Experimental research 47 3 Modelling 48 4 Instrumentation 48 5 Database 49 6 Draft proposal for guidance 49 4 Instrumentation 49 5 Database 49 6 Draft proposal for guidance 49 Publications 50 List of documents 50