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The main aim of this study was to describe the degree of cold exposure and occupational physical activity within three different outdoor occupational groups in northern Sweden using both technical measurements and self-reported survey items. The cold exposure and physical activity of workers in preschool, park and maintenance and power grid sectors (N = 133) were examined using a digital survey, temperature loggers and thigh-worn accelerometers. In the survey, 33% of workers indicated that they often or always felt cold at work, and 39% reported that they had inadequate knowledge about cold weather protection. The median (interquartile range, IQR) duration of working at ambient temperatures below 10°C was 131 (157) minutes. The physical activity while working outdoors was composed of sitting (20%), standing (54%) and walking (26%). About one-third of the participants reported that they often or always felt cold at their workplace, with an average of more than two hours spent outside at temperatures below 10°C. Possible remedies include increasing physical activity and improving thermal insulation of the clothing.

Background: There is a need for efficient screening for hand-arm vibration injury.

Aims: To evaluate the diagnostic test performance of screening questions for neurosensory injury in relation to clinical testing among hand-arm vibration (HAV)-exposed workers.

Methods: HAV-exposed subjects responded to a screening survey on subjective perception of touch, warmth, cold, and vibration, as well as grip strength and manual dexterity. Perception of monofilament, two-point discrimination, temperature rollers, and tuning fork was tested on the index and little fingers of both hands, while grip strength was tested using a hydraulic dynamometer. Diagnostic test performance characteristics were calculated based on crosstabulation of survey responses and outcomes of clinical testing.

Results: Our study recruited 225 subjects with exposure durations between one and 43 years. The sensitivity and specificity for the question about impaired ability to feel touch compared with monofilament was 65% and 71%; impaired ability to feel heat compared with temperature rollers 50% and 75%; impaired ability to feel cold compared with temperature rollers 39% and 77%; impaired ability to feel vibration compared with tuning fork 49% and 84%; reduced grip strength compared with hydraulic dynamometer 83% and 58%; and difficulty fastening buttons compared with two-point discrimination 40% and 76%, respectively.

Conclusions: The diagnostic test performance of the currently used screening survey for neurosensory injury among HAV-exposed workers needs to be improved. Future development should focus on establishing more specific questions, balanced response alternatives, and a more sophisticated interpretation of the responses, possibly using an index made up of several screening questions.

Objective: Workers exposed to hand-arm vibration (HAV) commonly experience discomfort in their hands when cold. There is a lack of diagnostic tests for such abnormal cold sensitivity. The main aim of our study was to evaluate the results of cold stress testing in relation to self-reported cold sensitivity among HAV-exposed workers.

Methods: We recruited 225 workers exposed to HAV who responded to a written screening question about cold sensitivity. Cold stress testing was conducted, where the right hand was immersed in 3.0 °C circulating water for up to 60 seconds. The tolerance time for immersion as well as continuous pain ratings on a digital visual analog scale (ranging from 0 to 100 millimeters) were recorded.

Results: The study sample consisted of 208 males (92.4 %) and 17 females, with a mean (SD) age of 40.6 (13.7) years. Among the 190 workers that completed cold stress testing, the mean (SD) tolerance time was 43.7 (16.4) seconds, mean (SD) maximum pain rating 69.8 (27.6) millimeters, and mean (SD) time to maximum pain 38.7 (15.9) seconds. Cold sensitivity was reported by 54 workers (24.1 %). Cold sensitivity was not statistically significantly associated with tolerance time or maximum pain rating, but symptomatic workers had a shorter time to maximum pain (p = 0.018).

Conclusions: Workers who reported cold sensitivity experienced a more rapid increase in cold-related pain, had a tendency towards shorter tolerance time but did not differ in maximum pain ratings. Further studies are needed to determine how to effectively investigate cold sensitivity among HAV-exposed workers.

Objectives: To prospectively determine the association between occupational biomechanical exposures and the incidence of surgically treated carpal tunnel syndrome (CTS) in Swedish male construction workers.

Methods: A cohort of 203 866 Swedish male construction workers who participated in a national occupational health surveillance programme between 1971 and 1993 were followed for CTS surgery between 2001 and 2019. Age, height, weight, smoking status and construction trade were obtained from programme records. CTS surgery cases were defined using the diagnostic code for CTS and surgical procedure code for peripheral median nerve decompression in the Swedish National Patient Register. Biomechanical exposure estimates were assigned by trade from a job-exposure matrix. The relative risk (RR) of CTS surgery for each biomechanical exposure was assessed with multivariable negative binomial regression modelling.

Results: The study included 3851 cases and the total incidence rate of CTS surgery was 137.6 cases per 100 000 person-years. Associations were found for upper extremity load (RR 2.6; 95% CI 2.2 to 3.0), repetitive wrist flexion and extension (RR 2.6; 95% CI 2.2 to 3.0), full wrist extension (RR 2.3; 95% CI 1.9 to 2.6), power grip (RR 2.5; 95% CI 2.2 to 2.9), pinch grip (RR 2.0; 95% CI 1.7 to 2.4), handheld tool use (RR 2.3; 95% CI 2.0 to 2.7) and hand-arm vibration exposure (RR 2.3; 95% CI 1.9 to 2.7).

Conclusions: Occupational upper extremity load and postural exposures were associated with increased risk for surgical treatment for CTS in this large construction worker cohort. Preventive actions and consideration of occupation on assessment are warranted.

Millions of people are exposed to cold environments daily. Adverse health risks are prominent for outdoor and cold storage workers. Therefore, a systematic risk management approach is highly motivated. This scoping review aimed to describe the current knowledge regarding risk management of cold exposure hazards in the occupational setting. We also examined differences between sexes in risk management practices regarding cold exposure.

The review included 25 peer-reviewed papers from 1980 to current in English and the Nordic languages, which could be divided into two categories: risk assessment and risk treatment. The risk assessment category included 17 papers, which investigated specific topics such as personal protective equipment, models for thermal balance, and individual differences regarding sex and body mass index. The risk treatment category included eight peer-reviewed papers, which emphasised the use of different protective or preventive measures and highlighted the importance of successful implementation and improvement of good practices.

To conclude, the previous literature on risk management of cold work was mainly oriented around technical risk assessment. However, there seems to be a lack of knowledge regarding implementation, resulting in inadequate protection for workers. Moreover, research was scarce regarding sex-dependent differences in risk management among workers exposed to cold.

Workers who use handheld vibrating machines such as grinders, hammers and chainsaws expose themselves to hand-arm vibration (HAV). Exposure to HAV may cause injuries to both the neurological and the vascular system. The occupational health services (OHS) in Sweden use a formal guideline for secondary prevention focusing on early detection of vibration-related injuries. The guide includes several screening tools, such as a screening questionnaire, clinical examinations, and laboratory tests. There are no studies, to our knowledge, on the diagnostic value of the separate items on symptoms in the screening questionnaire in relation to the laboratory tests or the clinical examinations performed during a medical examination among patients exposed to HAV. Furthermore, the recently presented ISO standard for HAV measurements (ISO/TR 18,750) has only been tested for vascular injuries and not neurological injuries. This research roadmap aims to evaluate separate items in a screening questionnaire on neurological symptoms in relation to laboratory and clinical tests among HAV exposed workers in the Arctic region of Northern Sweden. It also covers a comparison of the dose-response of the current ISO 5349-1 measurement standard and the new suggested standard ISO/TR 18,750 with the neurosensory outcomes. This manuscript describes the study rationale, design, methods, and significance.

Objectives: This study aimed to evaluate the influence of individual characteristics (sex, age, body mass index [BMI] and smoking habits) on the tolerance time, pain ratings and rewarming time of hand cold stress testing (CST).

Methods: We included 153 subjects (63% men) working in a Swedish open-pit mine (participation rate 41%). The right hand was immersed in 3 °C circulating water for up to 45 s. Pain ratings were registered every fifth second using a visual analog scale.

Results: The tolerance time (mean ± standard deviation) was 35 ± 12 s for men and 29 ± 14 s for women (p = 0.007). The youngest age group (18–29 years) had the longest tolerance time, while the oldest group (54–65 years) had the shortest (p = 0.005). Women had significantly higher pain ratings than men after 5, 10 and 25 s. The group with the highest BMI had the shortest rewarming time (p < 0.001).

Conclusions: Age and sex influenced the tolerance time of hand CST, while only sex affected the pain ratings and BMI the rewarming time. When performing CST in future studies, these parameters should be considered.

The primary aim of this study was to determine if occupational exposure to whole-body vibration (WBV) was associated with reporting neck pain. A cross-sectional study was conducted on a sample of the general population living in northern Sweden, aged 24-76 years. Data was retrieved through a digital survey that collected subjectively reported information on exposure to WBV and biomechanical exposures as well as neck pain. The study included 5,017 participants (response rate 44%). Neck pain was reported by 269 men (11.8%) and 536 women (20.2%). There was a statistically significant association between reporting occupational exposure to WBV half the time or more (adjusted OR 1.91; 95% CI 1.22-3.00) and reporting neck pain. In gender-stratified analyses, the same pattern was observed in men, while there were too few women to determine any association. We conclude that occupational exposure to whole-body vibration was associated with neck pain in men.

The literature on Raynaud’s phenomenon (RP) in the feet is scarce, especially in the occupational setting. The primary aim of our study was to investigate the occurrence of RP in the feet of miners. As part of the MineHealth project, written surveys and clinical examinations were completed by 260 Arctic open-pit miners working in northern Sweden and Norway (participation rate 53.6%). Data on RP were collected using standardised colour charts and questionnaire items. Clinical examination included assessing the perception of vibration and pain in both feet. There were eight women and three men who reported RP in the feet. Four also had RP in their hands but none acknowledged any first-degree relatives with the condition. Nine reported exposure to foot-transmitted vibration and one to hand-arm vibration. Seven showed signs of neurosensory injury in the feet. To conclude, the occurrence of RP in the feet of miners was 4.4%. Most cases with RP in the feet did not report the condition in the hands and were exposed to vibration transmitted directly to the feet. There were no reports of a hereditary component. Most cases with RP in the feet also had clinical findings suggestive of peripheral neuropathy in the feet.

This cross-sectional study aimed to describe exposure to cold climate and hand-arm vibration (HAV) as well as neurosensory and vascular symptoms and clinical findings among open-pit Arctic miners. It was based on data from questionnaires and physical examinations, including 177 men and 75 women from two open-pit mines in Sweden and Norway (response rate 54%). Working outdoors or in an unheated building or machine for at least two hours per day was reported by 44% and HAV exposure of the same duration by 10%. Neurosensory symptoms (e.g. reduced perception of touch) in the hands were reported by 47% and Raynaud’s phenomenon by 14%. In brief conclusion, the study showed that Arctic miners were commonly exposed to both cold temperatures and HAV. They also reported a broad range of neurosensory and vascular symptoms in their hands and had abnormal clinical findings related to the symptoms. The results emphasise the need for additional preventive measures in this occupational setting.