Sleepiness while driving has been regarded as a major cause of death due to traffic accidents. We compared the degree of sleepiness across five different working time periods (first, morning, post-lunch, afternoon, and last) among Korean bus drivers with different shift types (Daily two shift/Alternating day shift).

We interviewed 332 bus drivers with two shift types (Daily two shift, 128; Alternating day shift, 204). The questionnaire included demographic information (age, alcohol consumption and history of disease), a sleep disorder diagnosed by a doctor, job duration, the number of workdays in the past month, average working hours per workday and week, sleepiness while driving (Karolinska Sleepiness Scale), and sleeping time for both workdays and off-days. We conducted log-binomial regression analyses and produced prevalence ratios (PRs) of severe sleepiness (KSS ≥ 7) while driving with 95% confidence intervals (95% CI) to identify the difference in sleepiness for five working times between both groups.

For the first and morning periods, there were no statistically significant differences in the KSS scores between the two groups. However, from lunch to last driving, drivers with Alternating day shift had a much larger proportion of severe sleepiness than those on Daily two shift. Thirteen (10.2%), 2 (1.6%) and 7 (5.5%) Daily two shift workers reported severe sleepiness in the post-lunch, afternoon and last periods. In contrast, 81 (39.7%), 63 (30.9%) and 64 (31.4%) of Alternating day shift drivers experienced severe sleepiness during the post-lunch, afternoon and last driving periods (p < 0.0001). According to the log-binomial regression analyses, Alternating day shift was associated with severe sleepiness from lunch to last driving. After adjusting for job duration, alcohol consumption and sleeping time on workdays, the PRs were 3.97 (95% CI: 2.29–6.90) post-lunch, 18.26 (95% CI: 4.51–73.89) in the afternoon and 5.71 (95% CI: 2.51–12.99) for the last driving period.

We found that Alternating day shift bus drivers suffered from more sleepiness while driving from lunch to last driving than Daily two shift bus drivers. This difference may be because Alternating day shift drivers had more irregular work schedules and longer working hours per day and week.

With increasing use of medical radiologic procedures, wearing proper protector should be emphasized to reduce occupational radiation exposures. This research describes the rates of lead apron wearing for radiation protection and assessed occupational factors related to wearing rates for various types of healthcare professionals.

We conducted a self-administered questionnaire survey through a website, on-site visits, fax, and mail. Of the 13,489 participants, 8858 workers who could not completely separate themselves from radiological procedure areas. Their general characteristics (sex and age), work history (job title, duration of employment, and hospital type), and practices (frequency of radiation procedures, ability to completely separate from radiation, and frequency of wearing protective lead aprons) were examined.

The mean rate of lead apron wearing during radiologic procedures was 48.0 %. The rate was different according to sex (male: 52.9 %, female: 39.6 %), hospital type (general hospital: 63.0 %, hospital: 51.3 %, clinic: 35.6 %, dental hospital/clinic: 13.3 %, public health center: 22.8 %), and job title (radiologic technologist: 50.3 %, doctor: 70.3 %, dentist/dental hygienist: 15.0 %, nurse/nursing assistant: 64.5 %) (p < 0.001). By logistic regression analysis stratified by job title, use of lead aprons by radiologic technologists and nurses/nursing assistants was associated with hospital type and exposure frequency score. For doctors, apron wearing was associated with employment duration. For dentists/dental hygienists, apron wearing was associated with the exposure frequency score.

To improve working environments for healthcare professionals exposed to radiation, it is necessary to consider related factors, such as job title, duration of employment, and hospital type, when utilizing a planning and management system to prevent radiation-related health problems.