- October 2021
What is the difference, STANDARD vs OVERFLOW Capacity
Standard Capacity, sometimes referred to as Practical Fill Capacity (PFC) is the normal, commercial volume of a bottle.
- This is usually measured in cubic centimeters (cc), milliliters (ml), or ounces (oz).
- It is the amount of space inside the container for a given amount of product including headspace for product expansion.
- When a bottle is filled to standard capacity, the contents usually fill up to its shoulder area.
- Does not typically take into consideration displacement from a dip tube, dropper, or applicator.
Overflow Capacity (OFC), sometimes referred to as Brimful Capacity, is the maximum volume of a bottle if the contents were filled to the very top or to the brim of the bottle. It is used to estimate the exact amount of product a package can hold based on specific gravity of 1.0 or water. This is critically important when establishing the fill claim for a product (see below). It is also a “toleranced” dimension meaning expressed in a range so that it can be controlled by the factory in production. In the case of glass, the OFC is controlled during production by adjusting the weight of the bottle.
Why is it important to know the difference?
This will help customers determine how much of their product will fit into their bottle.
For example, you want to fill a 100ml bottle with 110ml of liquid – according to the specifications this bottle has a standard capacity of 100cc. However, if the technical specifications of the bottle show that the actual overflow capacity is 135cc, then it can potentially fill this bottle after verification of the filler's fill tolerance.
Keep in mind, however, that different product application and closure choices may require different headspace, so make sure you test fill your product and determine the best solution. Another reason to test fill products is because customers need to take into consideration liquid expansion due to temperature fluctuations.
In some cases this overfilling can cause different quality problems like leaking and breaking of the bottles.