ISS’ Guide to Reefer Shipping

  • 3 min read

Refrigerated shipping containers (or reefers for short) are temperature-controlled shipping containers used for transporting perishable and heat-sensitive products such as foods, drinks, pharmaceuticals, and chilled goods.

If you need to ship perishable goods, you’ll need to use a reefer. Read on to find out more about them and how to best go about reefer shipping.

How do Reefers Work?

Reefers distribute chilled air from the floor via T-shaped decking. This ensures the container produces a steady flow of air that is powerful enough to maintain the required temperature for the duration of the transit, even under harsh conditions. They have a temperature range of -35 degrees Celsius to 35 degrees Celsius - so they can also be used to transport products that need to be stored in a warmer ambient temperature.

Reefers VS Standard Containers

The biggest difference between reefers and conventional containers is the temperature control function. Normal containers are used to ship dry goods and do not have any temperature control. The two also differ in terms of size, design, power generation, and electrical distribution equipment. Reefers are smaller and contain individually powered refrigeration units. Because of this, they cost more than conventional shipping containers.

Types of Reefers

Just like conventional shipping containers, there are different types of reefers. The main types are closed reefers, Modified Atmosphere/Controlled Atmosphere (MA/CA) reefers, and Automatic Fresh Air Management (AFAM) reefers.

Closed Reefers

Closed reefers are conventional reefers that come in a single piece. They have an integral front wall and all-electric automatic cooling and heating units.

Modified Atmosphere/Controlled Atmosphere Reefers

MA/CA reefers are insulated containers that have air exchange systems that keep the atmosphere constant. The atmosphere in these containers can therefore be set accordingly to the deterioration rate of the cargo.

Automatic Fresh Air Management Reefers

AFAM reefers automatically adjust internal air exchange to maintain a constant temperature. Similar in its working to the MA/CA reefer, the AFAM reefer controls the composition of oxygen, carbon dioxide, and other gases. Their controls can be adjusted to extend the shelf life of the cargo, irrespective of outside conditions.

What is the Best Way to Handle Reefer Cargo?

Reefer cargo requires slightly more attention and care than regular, dry cargo. Failure to handle reefer cargo effectively can lead to product damage and reduction of shelf life. Here are the different cargo handling stages and the best way to do it:

  1. Pre-Shipment Handling: Your freight forwarder will take care of the majority of the pre-shipment handling stage. As the shipper, your only job is to provide accurate information about the products being shipped including their volume and weight, departure and destination ports, type of packing (boxes, drums, palettes, etc), temperature and humidity requirements, and any other handling specifications.
  2. Pre-Cooling: Reefers work by maintaining the temperature of cargo. They do not lower the temperature of the cargo. Because of this, you need to pre-cool your goods prior to container packing. Your freight forwarder will use specialised equipment, such as cooling tunnels, to maintain the temperature of your goods during container loading.
  3. Packaging and Stowing: As the shipper, you are responsible for packaging your products. When it comes to perishable items, you will need to package your products in such a way that allows for sufficient air flow and ventilation. Your freight forwarder will take care of stowage however, it is a good idea to ask them if they require any specific packaging specifications.

Dos and Don’t of Reefer Shipping

In order to prevent damage to your perishable goods during transit, follow these tips.


  • Pack cargo tightly so it is stable
  • Pre-cool your cargo
  • Ensure sufficient ventilation
  • Make sure your cargo is insured!
  • Package your products in a way that restricts air flow
  • Miss shipment deadlines and cutoffs, particularly for perishables.

Reefer shipping is more complex than shipping via conventional containers. In order to ensure seamless reefer shipping and the safe and hassle-free delivery of your cargo, get in touch with ISS today.

We are experienced in establishing effective and competitively-priced shipping strategies tailored to your business needs.

Contact our team here.