Things to know about DEF (Diesel Exhaust Fluid) and its Storage
Since the EPA-standardized engines were introduced in 2010, using systems that require fluids to be injected into outgoing exhaust for emission reductions is pretty common. With this in mind, there are some important facts that fleet managers and operators need to know about these fluids, commonly known as diesel exhaust fluids (DEFs). Other common industry names for these fluids include:
All diesel exhaust fluids must conform to the International Standards Organization (ISO) 22241-1. And no acceptable substitute is available. Note: DIN 70070 standard and diesel exhaust fluid specification limits of this standard are identical (ISO) 22241-1.
When a fleet considers purchasing DEF in bulk and storing it, here are a few things to consider:
- Storage temperature must be in range of 23-77°F (-5-25°C)
- Has to be in sealed containers to prevent contamination
- Not stored in direct sunlight
DEF has a minimum expected shelf life of 18 months in these conditions. If DEF is stored at higher temperatures for a prolonged time, shelf life will be decreased by about 6 months for every 9°F (5°C) above the highest storage temperature listed above.
Note that it is not recommended to store DEF in vehicles for over 6 months. If it is necessary to store DEF for a long period of time, perform periodic testing of the DEF to ensure that the concentration does not fall out of specification.
Testing should be performed if:
- The vehicle has been stored for prolonged time
- You suspect there is an addition of water to the DEF tank
The DEF will freeze around 12°F (-11°C) if the minimum specifications are present.