If a large earthquake hits during a workday, one of the biggest problems is not the shaking itself but what happens afterward: millions of people trying to walk home at once. In Japan this is known as the 帰宅困難者 (kitaku konnansha) problem, the "stranded commuter." After the 2011 Tohoku earthquake, trains stopped across the Tokyo area and huge crowds set off on foot, jamming roads and sidewalks for hours. That crush of people can be dangerous on its own, and it blocks emergency vehicles trying to reach the injured.
Why staying put is the official advice
The lesson authorities drew from that day is simple: do not rush home. National and local governments, including the Tokyo Metropolitan Government, now ask people to stay where they are for a period after a major quake rather than immediately setting out on foot. The guidance is often summarized as "一斉帰宅の抑制," discouraging everyone from leaving at the same time. Staying put keeps roads clear for fire trucks and ambulances, protects you from aftershocks, falling glass, and cold, and gives transport and phone networks time to recover.
The rule of thumb many companies and cities use is to wait roughly three days if you can, or at least until official information confirms it is safe to move. This is why some offices are required to stock water and food for their employees. Your job in that window is to be calm, gather reliable information, and let the situation settle before deciding your next step.
What to keep at your desk
Because you may end up spending a night or two at work or nearby, keep a small kit at your desk or in a locker. It does not need to be large. Aim for enough to keep yourself hydrated, warm, fed, and able to see and move safely.
- Water, a few small bottles, plus one or two shelf-stable snacks such as energy bars or crackers.
- A pair of comfortable walking shoes or sneakers, especially if you normally wear dress shoes or heels.
- A charged power bank and a cable, so your phone keeps working for information and messages.
- A foil emergency blanket, which folds down tiny and holds in heat if you are stuck somewhere cold.
- A small flashlight or headlamp, since stairwells and streets may be dark.
- Some cash in small bills and coins, useful when card readers and ATMs are down.
- A paper map of your area with your walking route marked, in case your phone dies or maps will not load.
A power bank is the item people most often wish they had, so it is worth thinking through what to charge first when battery is limited.
What to carry in your bag
Not everyone has a desk to store things at, so keep a lighter version in whatever bag you carry daily: a slim power bank, a small bottle of water, one snack, a folded foil blanket, a compact light, some cash, and a note card with key phone numbers and your home address written down. A dust mask and a whistle are small additions that earn their space.
Know your company's and city's plan
The single most useful thing you can do in advance is learn what your workplace and city expect. Ask whether your office has designated safe areas, stored supplies, or a staff check-in system. Many municipalities also designate 一時滞在施設, temporary shelters where stranded commuters can wait. Look up which ones sit along your route home, and agree with your family on how you will confirm each other's safety, for example through the disaster message board service (171).
It also helps to understand how official warnings are communicated so you can judge when conditions are improving. Our guide to warning levels 1 to 5 explains what each stage means and when to act.
Keep it calm and practical
An office and commute kit is not about fear. It is about turning a stressful, uncertain night into something manageable so you can wait safely and travel home when it is genuinely sensible to do so. Once you are home, your household supplies take over, which is why it is worth pairing this with a 7-day plan for a family. Pack the desk kit once, check the batteries and water every few months, and then largely forget about it until the day you are glad it is there.