Heat and Hot Weather Safety at Work

The first properly hot week of the year always seems to arrive before anyone is ready. Kitchens turn into saunas, delivery vans become ovens and the back office with no air flow gets sleepy by 2 pm. This guide helps you plan heat and hot weather safety at work now, in late spring, so your team stays comfortable, alert and safe when summer really starts.

Plastic water bottles packed in a cooler full of ice, ready to hand out on a hot day — A cooler of cold water by the door is the simplest heat plan you can start this week.

Key takeaways

Heat is a workplace hazard like any other: assess it, plan for it and write down what you will do.
In the UK there is no legal maximum workplace temperature, but employers must keep temperatures reasonable and assess the risks.
In the US, OSHA uses the general duty clause for heat hazards, and some states, such as California, have their own heat illness rules.
Water, rest, shade or cooling, and a gentle build-up for new or returning staff do most of the work.
Train everyone to spot heat illness early and know exactly who to call.

Most small businesses do not need a thick manual to handle hot weather. You need a clear picture of where heat builds up, a few habits everyone follows and a short plan for the hottest days.

A quick note before we start: this article is general information about workplace safety, not legal or medical advice. Rules differ by country, state and industry, so check the official guidance from your safety regulator and speak with a qualified health and safety adviser if your work involves serious heat exposure.

Why hot weather deserves a plan

Heat affects people gradually. A worker who feels fine at 10 am can be dizzy, irritable and making mistakes by mid-afternoon. Heat stress can lead to heat exhaustion and, in serious cases, heat stroke, which is a medical emergency. Long before that point, hot conditions also make accidents more likely: sweaty hands slip, tired people cut corners, and concentration drops.

There is a business side too: stuffy shops put customers off, staff who dread hot shifts leave, and stock can spoil. A heat plan protects people first and your service second.

What the rules say, in plain terms

UK. There is no legal maximum temperature for workplaces. Employers must keep indoor temperatures reasonable and assess the risks to workers, including from heat. If you have 5 or more employees, your health and safety policy and risk assessment must be written down.
US. OSHA uses the general duty clause to address heat hazards, which means employers should keep the workplace free from recognized hazards that could cause serious harm. Some states, such as California, have their own heat illness rules, so check your state's requirements as well.
Elsewhere in Europe. National rules vary, so check your national labor or safety authority.

No legal maximum UK law sets no maximum workplace temperature, but employers must keep temperatures reasonable and assess the risks from heat UK workplace health and safety guidance

Spot where heat builds up in your workplace

Walk around your premises and your routes with fresh eyes, ideally on a warm afternoon. Heat risk is a mix of the environment, the work and the person, so look at all three.

The environment

Rooms with big south or west facing windows, skylights or flat roofs.
Kitchens, bakeries, laundries and anywhere with ovens, fryers, dryers or steam.
Vans, trucks and delivery vehicles that sit in the sun.
Outdoor work with little shade: gardens, building sites, markets, car parks, events.
Storerooms, lofts and back rooms with poor air flow.
Humid spaces, where sweat cannot evaporate and cool the body.

The work

Heavy lifting, digging, carrying or fast-paced physical tasks.
Protective clothing, aprons or uniforms that trap heat.
Long shifts without natural breaks.

The person

New starters and people returning from time off, who have not adjusted to the heat yet.
Staff who have told you about a health condition, pregnancy or medication that may affect them. Handle this privately and respectfully.
Young workers and older workers, who may need closer attention.
Anyone working alone, where nobody would notice early signs.

Pro tip

Put a simple thermometer in each hot spot and ask whoever opens up to note the reading at the start of the shift and again mid-afternoon. A week of notes tells you more than any guess, and it gives you evidence that you are monitoring conditions.

The core controls: water, rest, shade and cooling

Once you know where the heat is, the fixes are usually practical and cheap. Think in layers: reduce the heat at its source first, then change how work is done, then support individual people.

Reduce the heat itself

Use blinds, reflective film or shades on sunny windows.
Open windows and doors early in the day when the air is cooler, then close them as it heats up outside.
Add fans, extraction or air conditioning where it makes sense, and keep it serviced.
Move heat-producing equipment away from workstations or switch it off when not needed.
Set up shade outdoors: canopies, umbrellas or a shaded rest spot.

Change how and when work happens

Schedule heavy or outdoor tasks for early morning or later in the day.
Rotate people between hot and cooler tasks.
Add extra short breaks on hot days rather than one long break.
Use mechanical aids such as trolleys and lifts so people carry less.
Avoid lone working in the hottest conditions, or set up regular check-ins.

Support each person

Provide easy access to cool drinking water and encourage people to drink regularly, not only when thirsty.
Relax uniform rules on hot days where safety allows: lighter fabrics, sleeves rolled, no jackets.
Provide sunscreen and hats for outdoor workers.
Build heat tolerance gradually for new and returning staff with shorter or lighter shifts at first.

Common mistake

Relying on a single fan in a hot kitchen and calling it a plan. A fan blowing hot air around can make people feel better for a moment without lowering the real risk. Pair cooling with schedule changes, more breaks and water, and check how staff actually feel.

People walking along a sunny street, with one person holding a parasol for shade from the bright sun — Shade, timing and a little extra rest make bright summer days far safer for outdoor workers.

How to build your hot weather plan step by step

You can draft a workable heat plan in an afternoon. Keep it short enough that people actually read it.

List your hot spots and hot tasks. Use your walk-around notes and thermometer readings.
Decide your triggers. Choose what will switch on your hot day measures: a local weather warning, a forecast you consider hot for your area, or a reading on your own thermometer. Keep it simple and consistent.
Write your hot day measures. For example: start outdoor work earlier, add a break every hour, move deliveries to the morning, open the cool room for rest breaks.
Assign a heat lead for each shift. This person checks the forecast, sets up water and shade, and watches for early signs of heat illness.
Plan for emergencies. Write down what to do if someone shows signs of heat illness, who calls the emergency services and where your nearest first aid kit is.
Brief the team. Run a 10-minute talk before the first hot spell and repeat it for new starters.
Review after each hot spell. Ask staff what worked and what did not, and update the plan.

A hot weather plan template

Copy this table into a document or spreadsheet and add one row per hot area or task. The details below are made-up examples for a small cafe with a delivery service.

Area or task	Heat risk	Everyday controls	Hot day measures	Who is responsible
Kitchen line (example)	Ovens and fryers, little air flow	Extraction fan on, water station, light uniforms	Prep heavy items before 10 am, extra 10-minute break each hour, rotate with front of house	Head cook
Delivery van (example)	Sun on the vehicle, loading and carrying	Park in shade, cool box of water in cab	Move the longest route to early morning, check-in call at midday	Shift manager
Outdoor terrace (example)	Direct sun on staff serving tables	Umbrellas, sunscreen at the counter	Shorten terrace shifts, swap staff every hour	Front of house lead

Recognizing heat illness and responding fast

Everyone on your team should know the early signs of heat illness, because the person affected often does not notice their own symptoms. Common warning signs include heavy sweating, headache, dizziness, nausea, muscle cramps, unusual tiredness, confusion and pale or flushed skin. More serious signs, such as confusion, collapse or a person who stops making sense, need urgent medical help.

Keep your response simple and practiced:

Move the person to a cooler, shaded place and stop their work.
Loosen tight clothing and help them cool down with water, fans or cool cloths.
Offer sips of water if they are alert and able to drink.
Do not leave them alone, and call the emergency services if symptoms are severe or do not improve quickly.
Record what happened and review whether your controls need to change.

Follow the first aid guidance from your official health service or first aid provider.

Hypothetical example

Imagine Sam, who runs a small garden maintenance business with four staff. Last summer, one new team member felt faint after a long afternoon of hedge cutting. This year Sam starts earlier on hot days, gives every van a cool box of water, pairs new starters with an experienced colleague and schedules heavy jobs for the morning. Nothing fancy, but the team now knows the plan.

Remote, mobile and customer-facing staff

Heat planning is not only for people on your premises. Think about anyone who works for you somewhere else.

Mobile and field staff. Cleaners, trades, delivery drivers and mobile service providers often work in other people's homes or in vehicles. Give them water, a way to report heat problems and permission to pause or reschedule if a site is dangerously hot.
Home workers. If staff work from home, remind them to take breaks and set up in the coolest room they can. Your remote work policy can mention hot weather alongside hours, equipment, data security and expenses.
Event and market staff. Outdoor events and pop-ups need shade, water and a rota that limits long stretches in direct sun.
Customers. If customers queue outside, offer shade and water where you can.

Talking to your team about heat

A heat plan only works if people use it. Ask your team where they feel hottest and what would help. The answers are often cheap: a moved rota, a second water jug, a blind on one window.

Make it normal to say "I need a few minutes in the shade." If the owner takes a water break, everyone else will too.

If you employ young workers over the summer, remember that child labor and young worker rules limit hours and tasks, and take extra care with heat. In the US, FLSA child labor rules apply to under-18s, with tighter limits for 14 and 15 year olds. In the UK, children below school leaving age face restrictions and may need a local council work permit. Check the current rules before you set rotas.

Your hot weather action checklist

Walk your premises, vehicles and routes to find hot spots and hot tasks
Place thermometers in the hottest areas and record readings for a week
Check current heat guidance from your country or state regulator
Set clear triggers for switching on hot day measures
Set up water stations, shade and a cool rest area
Plan earlier starts, task rotation and extra breaks for hot days
Give new and returning staff a gradual build-up
Train everyone on the signs of heat illness and the emergency steps
Name a heat lead for each shift
Add heat to your written risk assessment and review it after each hot spell

Frequently asked questions

Is there a temperature at which staff can stop working?

In the UK there is no legal maximum workplace temperature, but employers must keep temperatures reasonable and act on the risks they find. In the US, there is no single federal temperature cutoff, and some states have their own heat rules. Rather than waiting for a magic number, set your own triggers and measures in your heat plan and check official guidance.

Do I have to install air conditioning?

Not necessarily. Many workplaces manage heat with shade, ventilation, fans, schedule changes and extra breaks. Your duty is to assess the risk and take reasonable steps.

Can I relax the dress code on hot days?

Usually, yes, as long as safety equipment stays in place. Lighter uniforms, shorts where appropriate and removing ties or jackets are common hot weather changes. Write the rule down so everyone knows what is allowed.

Should heat be part of my risk assessment?

Yes. Heat is a hazard you can foresee, so include it in your general risk assessment and update it each spring. In the UK, employers with 5 or more employees must keep a written risk assessment.

The bottom line

Heat and hot weather safety at work comes down to a few habits: know where the heat builds up, keep water and shade close, change the timing of hard work, build people up gradually and act fast when someone feels unwell. Write it down, name a heat lead and talk it through with your team before the first hot spell.

Spend an hour this week walking your workplace with a thermometer and a notepad. By the time summer arrives in full, your team will have a plan that keeps them safe and your business running smoothly.