In summer the biggest risk to a heat-sensitive package is not the drive. It is the time the package spends standing still: in a parked vehicle, on a doorstep, or on a loading dock in the sun. Planning a summer delivery in Montréal means shrinking that waiting time, packing for a warmer day than the forecast suggests, and choosing delivery windows when someone is there to receive the item.
Quick answer
- The main summer risk is dwell time, meaning the minutes a package sits in a parked vehicle, on a doorstep, or on a dock.
- Transport Canada notes that the inside of a vehicle can heat up very quickly, even on days that are not very hot or sunny.
- Pre-condition cold packs, leave margin for delays, and ship to a window when a person can receive the package.
- June 24, July 1, long weekends, and summer road work all change timing, so book earlier than usual.
Summer Risk Is About Standing Still
A vehicle with working climate control, moving between stops, is a stable environment. The trouble starts when it stops. A parked vehicle in the sun, an unattended package on a doorstep, a pallet waiting on a loading dock, and a hot lobby with no one at the desk are the places where heat builds up.
Transport Canada's guidance on children in hot vehicles says that a vehicle's interior temperature can rise very quickly, even on days that are not very hot or sunny. That warning is about people, but the physics apply equally to a box of medication. The practical conclusion is the same: do not plan any stop in which a conditioned item waits in a parked vehicle.
Which Items Care Most About Heat
| Item | Why heat matters | Summer handling |
|---|---|---|
| Medication with labelled storage conditions | Drugs are expected to ship under their labelled conditions unless a justification exists | Follow the label, minimize dwell time, and report any deviation |
| Refrigerated products | The label may call for a refrigerated range, commonly 2–8 °C | Use a validated pack-out with margin for delay, and hand it to a person, not a desk |
| Laboratory specimens | Stability depends on the test and the sample | Follow the laboratory's own transport instructions |
| Dental work such as impressions and wax try-ins | Heat can distort or soften materials, see our dental lab courier guide | Rigid labelled case, kept out of sun and out of parked vehicles |
| Batteries and powered devices | Heat stresses cells, and some batteries are dangerous goods, see our dangerous goods guide | Keep out of direct sun and avoid long waits |
| Adhesives, reagents, and test kits | Some are sensitive to heat even when not refrigerated | Check the product sheet and pack accordingly |
Adjusting the Pack for a Warm Day
- Pre-condition the packs. Cold packs that start at the right temperature last longer than packs that were rushed out of a freezer.
- Keep the validated pack-out. Do not improvise a different arrangement because it is summer. If the supplier has a summer configuration, use it.
- Leave margin. Plan for the trip to take longer than the map says.
- Pack close to pickup. A box that waits two hours in a warm office has already used part of its margin.
- Label it clearly. “Keep out of sun” and “hand to a person” labels help everyone downstream.
- Consider a logger. A temperature indicator or logger shows what happened and supports a decision if something goes wrong.
For the fundamentals of how temperature-controlled shipping is planned, see our guide to cold chain logistics.
Dwell Time: The Number to Shrink
| Where dwell happens | How to cut it |
|---|---|
| At pickup | Have the package sealed and at the door when the courier arrives |
| In traffic or at a stop | Use a direct run with no unrelated stops, and keep the cabin cooled |
| At the loading dock | Book a receiving time and tell the recipient when the courier is close |
| In the lobby or at security | Pre-announce the courier and name the person who will meet them |
| When the recipient is absent | Call before the run and agree on the fallback, which is never to leave it unattended |
The Summer Calendar in Québec
Summer in Québec has its own rhythm, and it affects timing.
- June 24 and July 1. Both are statutory holidays in Québec, and some recipients are closed. Check the receiving hours rather than assuming a normal weekday.
- Moving season. Many residential leases in Québec have traditionally turned over around July 1, which fills streets with moving trucks and tightens curbside space in residential neighbourhoods.
- Road work. Summer is the main season for construction, so lanes close and detours appear. The government's Québec 511 site posts current road conditions.
- Long weekends. Fewer people are at receiving points, and some labs and clinics run on reduced hours.
Our guide to winter courier delivery covers the opposite problem. Both seasons reward the same habit: tell the courier the constraint early.
What to Tell the Courier on a Hot Day
- The temperature class and the label condition.
- How long the item can spend outside its range, if you know.
- The window when a person will be at the destination.
- What to do if nobody is there: call you, wait, or return.
- Whether a logger or indicator is in the package, and who reads it.
If a Shipment Warms Up
Do not guess. Report what happened, with times and any logger data, and let the owner of the product decide whether it can be used. Health Canada's storage and transportation guideline expects excursions to be investigated and documented, with decisions based on evidence such as stability data. Our pharmaceutical courier compliance basics guide explains what that process looks like in practice.
Frequently Asked Questions
Is a standard delivery van safe for heat-sensitive medication in July?
Only if it has working climate control, the stops are short, and the item never waits in a parked vehicle. Ask the courier how conditions are maintained and how dwell time is limited. Labelled storage conditions still apply regardless of the season.
Can a courier leave a heat-sensitive package on a doorstep or at a reception desk in summer?
No. Conditioned items should go to a person who can take them straight into proper storage. If nobody is available, the courier should call the sender instead of leaving the package where the sun or a warm lobby can reach it.
How much extra coolant should I add in summer?
Follow the validated pack-out for your product. Do not improvise a quantity. If your supplier has a summer configuration, use it, and ask them how much delay it tolerates.
What should I do if a package spent longer in the heat than planned?
Record the times, check any logger or indicator, and tell the product owner. They decide whether it can still be used, based on stability data. Do not assume it is fine or ruined without that information.
Do I need a temperature logger for summer deliveries?
It is worth considering whenever the label conditions are strict or the product is valuable. A logger produces evidence for a decision, and it shows the courier and the recipient exactly where a problem occurred.
Beat the Heat by Shrinking the Wait
Summer deliveries go well when nothing waits: the package is ready at pickup, the route is direct, the recipient is expecting it, and the handoff is to a person. Pack as the label requires, plan around the calendar, and agree in advance on what happens if the plan slips.
Rush Expedited Courier operates climate-controlled vehicles for temperature-sensitive items, with dispatch available around the clock. Describe your shipment through the quote form, and read about our medical courier service.
Sources and Further Reading
- Transport Canada: Dangers of hot vehicles and children
- Health Canada: GUI-0069, guidelines for the storage and transportation of drugs
- Québec 511: road conditions and traffic