As a follow up to Part 1 of Factors Affecting your Picking Efficiency, this guide continues with additional aspects to consider.

As previously discussed, industry reports indicate that labor costs make up approximately 50-70% of the total operational expenses in a distribution center. Picking labor alone can account for about 30-50% of these labor costs.

This means that, depending on the efficiency and automation of the picking processes, picking labor can represent roughly 15-35% of the total operational costs.

This guide continues to provide insight as to the fundamentals to ensure your picking operations are as efficient as possible.

1. Wrong Sizing Picking Bins
This aspect goes in line with slotting from the previous portion of the guide. All too often, companies let the pick locations evolve without constraints or keeping the inventory on hand inline with picking and replenishment targets.

When this happens the overall size of the picking footprint continues to grow. After a few peak seasons without oversight, the picking footprint and pick path has become highly inefficient. Every wasted step is labor dollars wasted.

Companies should develop the proper analysis to keep a watchful eye on the inventory requirements for each SKU and continually adjust the size of pick bins. This will keep the overall footprint and pick path as efficient as possible. This is a task that is best suited after each peak season, or anytime the SKU base turns over significantly, and one that we focus on during operational assessments.

2. Paper Picking Versus Scanning, Voice or Other Automation
There is no doubt that paper picking is the least efficient way to pick orders. Paper-based picking systems are prone to human error.

According to a study by the Aberdeen Group, error rates in manual picking processes can be as high as 1-3% compared to less than 0.5% in barcode scanning. As these errors are caught at packing and shipping, labor dollars are lost having to correct these issues.

Paper picking is also significantly slower. Pickers have to continually reference the pick sheets which present all lines versus just the active pick to be completed. A study published by Supply Chain 24/7 highlights that warehouses using barcode scanning experienced a 15% increase in order fulfillment speed and a 20% reduction in labor costs compared to those using paper-based systems.

3. Not Developing Efficient Paper Based Picking
If you are forced to pick from paper, there are several aspects you should consider making the process more efficient. Consider implementing the following:

Location Sequence. This seems like an obvious one, but you would be surprised how many systems we see that are pick from paper without the picks being in location sequence. Instead, they are often in Item # sequence which then forces the warehouse to slot everything by Item # which destroys efficiency.
Separate location designators for easier reading. If you have the typical Aisle-Bay-Level-Position as your location schema, consider separating those which a hyphen or a space so that it is easier for the picker to visually understand. If you aren’t using this type of location schema, then you should think about what it would take to implement.
Proper Call-outs on Paper. For critical notes or warehouse messages, ensure that these are called out appropriately for the picker to see and not skip. This could be using shading, colors or enlarging the font and bold text.

4. Not Creating Logical Picking Batches
This aspect is where good systems are critical. Creating logical picking batches will create some of the best efficiencies in picking. These pick batches should organize the picking work, a few examples include the following, all with the goal of minimizing walking.

Single Line Orders. This is one of the greatest ways to gain efficiency. Group all single line orders in a way that allows a picker to go to a single location and pick all the units to satisfy those qualifying orders versus going back to the same pick bins over and over.
Ship Alones. Batch ship alone orders separately so they can be efficiently picked. Additionally, group those ship alones that can be shipped in the existing packaging by simply applying a shipping label. The remaining ship alones can be sent to a packing line for overboxing. These can be easily picked to a pallet jack for efficiency.
Zone Based Picking. This has a lot of avenues that could be considered, including batching all multi-line orders that can be fully picked from a single zone versus multi-line orders that cross zones. Additionally, companies implement zone based pick and pass. This is where one picker is responsible for the picks in one zone and then passes the order(s) along for another picker to finish picks from the next zone. This is best accomplished with conveyors and sortation but can also be handled in a manual way. These are key considerations when performing operational assessments.

5. Basket Analysis for Slotting
This analysis will take some data, but for some companies is vital to understand how to slot products. Basket analysis, also known as market basket analysis, is a data analysis technique used to understand the purchasing behavior of customers by examining the combinations of items they frequently buy together.

From a picking perspective in a warehouse, basket analysis can provide valuable insights to optimize order picking processes. Specifically, focus on the Apriori algorithm which is a method of basket analysis. Its purpose is to perform the technical task of identifying which items frequently appear together and deriving rules about their relationships.

This analysis will help to identify those items that should potentially be slotted together in the picking footprint.

6. Not Considering Automation and Robotics to Assist in Picking
This one is left for last on purpose. It is imperative that we as operational professionals focus on the fundamentals before trying to throw automation at an issue. Companies that do this often find that they have thrown good money after bad, and the ROI becomes delayed or disjointed.

Companies that have a strong adherence to the fundamentals will deploy automation more effectively. Some forms of automation and robotics to reduce labor costs include the following:

Bar Code Scanning. As previously discussed throughout this guide, companies should seek to move away from paper-based systems as quickly as possible. Regardless of how sophisticated (or not) their business is, there are affordable systems for even the smallest companies. These entry level systems can be as low as $200-$300 per user per month. Even at this price point there is an easy ROI.
Pick to Light and Put to Light. Pick to light systems are just as easy as that. A light is affixed to a pick location, when a pick for that location is requested, the light is illuminated, and a display shows the quantity to be picked. These are generally used in high pick density areas such as small bin shelving, carton flow, etc. The same concept is used for put to light, once items are picked, they are put to locations using a light system as well. Several manufacturers utilize this on pick carts as well as lighted put walls.

Voice Picking. These systems utilize a head set worn by a picker. The headset utilize voice technology to direct the picker to a pick location and dictates the quantity to be picked. The picker confirms the location by reading a check digit at the specific location. This allows the picker to be hands free, making it ideal for large, awkward and heavy items, as well as whereas the picker may need to inspect an item before proceeding.
Picking Co-bots. These include manufacturers like 6River, Locus, Geek+ and others. These are also popular among a wide range of 3PLs. They allow for batching of orders, remapping of picking aisles and destination points, etc. Even though many are used in consumer picking, these are capable of handling a wide assortment of wholesale orders depending on the order and item characteristics.
Goods to Person. These include some of the widest range of technologies from Vertical Lift Modules (VLMs) to systems like Opex and AutoStore. VLMs being on one end of the spectrum from an ease of use to implement and setup, compared to systems such as Opex and AutoStore. This is also true from an investment perspective. There are other options that work without the contained structure, this would include options like Exotec. This system pulls totes from racking and delivers them to a pick area that can be re-mapped as needed for expansion or relocation.