vibration; seat design; physiology and vigilance of train driving. Discussion of each subject is divided into three sections: survey of relevant literature, conditions on domestic locomotives, and recommendations to improve present models and future design. 6.2.34 (66602) Hawkins, N.M., Atha, J., and Ashford, N. Behavioural observations of passengers boarding a slow speed conveyor. Transport Technology Assessment Group, Department of Transport Technology, University of Technology, Loughborough, Report No. TT 7411 Nov, 1974, pp 86. This paper deals with some ergonomic aspects of passenger conveyor systems. A film was taken of passengers loading a slow speed travellator at Heathrow Airport, London. Behavioural analysis of the film established a relationship between a passenger's 'boarding style' and the likelihood of subsequent balance problems. Illumination 6.2.35 (66622) Tregenza, P.R., et al. Consistency and variation in preferences for office lighting. Lighting Research and Technology, 1974, 6.4 205-211. In an experiment in which female office workers could freely adjust the lighting in a full-size model office the following results were obtained: tile level of lighting chosen varied with the initial lighting in the room; the relative level chosen by individual subjects remained consistent despite variation in the absolute illuminances; subjects were consistent between experimental sessions several days apart; and there was a significant positive correlation coefficient between the age of subjects and chosen desk illuminance. Preferred illuminance ratios were obtained; no significant variation of the ratios with task illuminance was found, but there were similarities between the lighting choices in the laboratory and lighting in subjects' normal workplaces. 6.2.36 (66624) Illuminating Engineering Society, Roadway Lighting Committee, Roadway Sign Lighting Subcommittee. Roadway sign illumination. Jo urna l of the llluminating Engineering Society, Oct 1974, 4.1, 78 81. Roadway signs should convey the same message at all times to the motorist. Recognising this need, the Roadway Sign Lighting Committee was formed for the purpose of preparing a document that would provide a uniform means of lighting signs so that the message will appear the same night or day. This report, an inherent part of roadway lighting, is the result of that study. Noise 6.2.37 (66634) Anon. American Conference of Governmental Industrial Hygienists proposed threshold limit value for noise. American Industrial Hygiene Association Journal Nov-Dec, 1968 29.6, 537-540 Abstr in Occupational Safety and Health Abstracts (CIS 2020 - 1969). The American Conference of Governmental Industrial Hygienists has proposed the following threshold limit values for noise: for broad band noise 92 dB, as measured on the A-scale of a sound level meter (dBA), for exposures of 5 to 8 h per day; 97 dBA for 2 to 4 h; 102 dBA for 1 to 2 h; and 107 dBA for less than 1 h. For narrow bands of noise or pure tones, the threshold limit values should be reduced by 5 dB. The above limits do not apply to impulse or impact type of noise; it is recommended that exposure to this type of noise should not exceed 140 dB peak sound pressure level. 6.2.38 (66651) Guignard, J.C. Noise in combination with other stressors. In: Symposium on Working Place Safety Proceedings, 22-26 Jul. 1974, Bad Grund, Germany. The adverse effects of noise include temporary and permanent threshold shift in hearing; interference with communication (which can be dangerous, as well as affecting productivity); impairment of skilled performance in certain kinds of task; and physiological stress. Some of these responses can be modified by the simultaneous presence of other stressors, such as vibration, heat, workload stress, sleep loss, and other biological or physical factors in the work situation. However, the interaction of other stressors with noise is varied and frequently complex, and cannot simply be summarised as always additive. In some circumstances, for instance, human performance appears paradoxically to be improved by the addition of noise when it is degraded by another stress (eg, sleep loss). Again, temporary threshold shift due to intense broad-band noise is sometimes lessened by simultaneous whole-body vibration. The interaction between noise and other stressors can accordingly be specified only for particular combinations of factors, for it varies not only with the nature of the other stressors in the combination but also with time and with the level and the relative severity of the noise and the other stressors. Specialised and protective cloth ing and equipment 6.2.39(66715) Anon Development of standards for industrial and firefighter's head protective devices T. Dayton Brown Testing Laboratories Division, Test Report DTB06R73-1273. National Institute for Occupational Safety and Health, Rockville, Maryland, USA, 1973, 2 vols, pp274 Abstr in CIS Abstracts (CIS/74-1415) A study of 2564 head injuries which occurred in 1970 in 64 industries of the State of New York is followed by anthropometric, physiological and other considerations concerning the requirements of protective helmets. Existing standards are evaluated as regards performance and test require- ments, and recommendations are made. Currently available helmets appear to offer limited protection only and are not well suited to the broad range of conditions found in industry. Recommended standards pertaining to performance, testing and use are given in Vol 2. 6.2.40 (66716) Sarraile, S.R. The protective performance of crash helmets, Mar. 1973, pp 41 Abstr in Scientific and Technical Aerospace Reports (Report No. ARL/SM-Note 390) Crash helmets for use in agricultural aviation should provide good impact protection, be light and comfortable and give acoustical protection. Satisfactory impact protection should be assured by standard specifications. To examine the performance of current hehnets and suitability of typical standards, a series of tests was conducted on ten types of helmet, and their performance was compared with standard requirements and head tolerance to impact, Standard specifications were reviewed and it was concluded that they should, and could be modified to require improved protection. The comfort aspects were investigated in a brief field trial to indicate design characteristics suitable for aviation helmets. Applied Ergonomics June 1975 119