Pros & Cons of EPS vs. PUR Insulated Shipping Coolers


EPS (aka expanded polystyrene or Styrofoam) insulated shipping coolers are the typical material of choice for human & animal health companies when shipping specialty pharmaceuticals and biologics. It’s proven to provide temperature-controlled protection for specialty products–as long as they’re delivered on time.

Many companies using EPS shipping coolers are facing rising freight costs, increasing regulatory oversight and other packaging-related issues.

The good news is there’s an alternative to combat these issues, keep your product viable longer, AND cut shipping costs. If you’ve ever wondered how to reduce or eliminate overnight shipping costs from your supply chain, this might be your answer.

Here’s how to choose whether EPS or PUR insulated shipping coolers are best for your product.


  1. Advantages & disadvantages of passive EPS insulated shippers
  2. 5 ways PUR coolers can cut shipping costs

Advantages & disadvantages of passive EPS insulated shipping coolers

EPS (Expanded Polystyrene) is a type of passive ISC (insulated shipping cooler). Passive temperature-controlled packaging systems rely on refrigerants (wet/dry ice, gel pack, gel brick, phase change material) to maintain temperature ranges. Note: Active temperature-controlled packaging systems are refrigerated shippers which require a power source (e.g. leased containers with advanced temperature controls that are often powered by electricity and/or battery climate controlled truck) to maintain temperatures.

Advantages of using passive EPS ISCs (molded or panel):

  1. Lightweight
  2. Inexpensive
  3. Best suited for temperature-sensitive materials shipped within a short transit duration

However, EPS insulated shippers also have disadvantages:

  1. R-value is the capacity of an insulating material to resist heat flow. The higher the R-value, the greater the insulating power. EPS R-Value is low – it can only maintain temperatures in the 2-8°c range for 24-36 hours. As a result, products must be shipped via costly Overnight and/or via a practice known as “stone skipping” to ensure internal payload temperatures are maintained during transit.
  2. EPS uses a bulkier design that requires significant warehouse and freight truck space, which increases total costs.
  3. EPS comes with an increased risk of potential product failures and/or excursions due to unforeseen events beyond your control (such as transit delays)
  4. EPS packaging is less resistant to moisture, heat, certain chemicals, and other factors that can end up damaging your product. (EPS is actually a great fuel for fire once it hits 280 degrees.)

5 cost-saving reasons to choose PUR insulated shippers as an alternative to EPS

  1. Reduce or eliminate overnight shipping
  2. Reduce risk of product failures & excursions
  3. More durable & sustainable
  4. Take up less space
  5. More extreme temperature control (can be colder and longer)

Many companies that require cold chain packaging are turning to PUR (polyurethane) insulated shipping coolers as an alternative to EPS. Why? Simply because the cost savings are enormous.

On the surface, PUR coolers seem to be more expensive because it requires a higher upfront investment per container. However, when companies review their total cost of ownership, many times often than not, they generally reveal up to 40% cost savings by switching to PUR from EPS shipping coolers. across the entire supply chain.

Passive PUR ISCs (polyurethane insulated shipping coolers) combat common issues with EPS. PUR shippers protect temperature sensitive products longer under more extreme weather conditions, significantly reducing total cost of ownership.

shipping costs and distance of PUR vs EPS insulated shipping coolers for cold chain packaging
BEFORE (top) with all overnight shipments in EPS and AFTER (bottom) with 2-day shipments in Chill-Pak PUR coolers

1.   Stop shipping overnight. Start shipping ground. 

PUR insulated shipping coolers eliminate Overnight shipping. Their R-Value is significantly higher than EPS, which allows longer thermal performance.

Product can be shipped via standard Ground because 2-8°c temps are maintained for 48-96 hours.

2.   PUR material properties are more consistent and stable, reducing risks of product failures and excursions. 

This is especially important when protecting high value, high dollar temperature sensitive products.

3.   They’re more durable and sustainable

Physical properties of PUR are more suitable for heavier payloads under closed distribution loop (reverse logistics) programs, which put additional stress on insulated shipping coolers.

It also provides better protection against transit shock and extreme environmental conditions.

4.   PUR coolers take up less space in every stage of the supply chain. 

They have a smaller profile and use less refrigerant, reducing freight and warehouse footprints.

5.   PUR is better for extreme temperature control.

It’s a superior insulator and a more cost-effective solution than EPS when shipping products requiring frozen internal payload temperatures (-80°c to 0°c).

PUR vs EPS Insulated Shipping Coolers: Stop Shipping Overnight, Start Shipping Ground

Considering all of the above factors, PUR coolers can easily save you 40% (or more) through:

  • Ground shipping
  • Reduction in packaging size and space
  • Improved product viability
  • Reusability

EPS still has its uses. However, companies looking to ship products in extreme cold over a longer shipping cycle can certainly benefit from reviewing PUR as an alternative cold chain packaging solution.

For more information on PUR shippers and impact on your supply chain, check out our cold chain packaging solutions or contact us here!