Obayashi Corporation Initiates Work Hour Changes at Construction Sites During Peak Heat Periods

As the increasingly severe summer heat becomes a significant societal issue, Obayashi Corporation is initiating an effort to shift working hours at qualified construction sites across Japan during the peak heat period (July–August) to further mitigate heatstroke risks.

1. Background
According to reports on casualties due to heatstroke in the workplace (2021–2025), the construction industry has the second-highest number of incidents following the manufacturing industry, making the reduction of heatstroke risks an urgent priority. These measures are essential not only for protecting the lives and health of skilled workers but also for ensuring construction quality and stable project execution.

Obayashi has consistently implemented heatstroke prevention measures, including作業 management based on WBGT (Wet Bulb Globe Temperature) values, ensuring rest periods, and introducing temporary air conditioning equipment. Additionally, since last year, all personnel involved in site work have been required to wear air-conditioned clothing and wearable devices that monitor and alert them to heat-related risks. Building on these measures, Obayashi is now focusing on adjusting working hours.

2. Initiative Overview
This initiative targets the period from July to August, when heatstroke risks are at their highest. To concentrate work during hours before temperatures and WBGT values rise, working hours at construction sites will be changed to 7:00 AM–1:00 PM.

In cases where this schedule may affect project progress, adjustments will be made throughout the year, such as extending work hours during cooler months, to ensure both worker safety and the maintenance of quality and productivity.

Target Period: July – August
Target Sites: Domestic construction sites (implementation decided based on site-specific environment and content)
Working Hours: 7:00 AM – 1:00 PM (Standard hours are typically 8:00 AM – 5:00 PM)

3. Future Outlook
Obayashi will continue to enhance heatstroke prevention measures at construction sites and remains committed to improving site safety and creating better working environments.