What’s Slowing Down Your Workflow?

By Steele Young
FLOW—to proceed continuously and smoothly

Why does it take three days to deliver a pair of glasses when the total of all manufacturing steps is 48 minutes? Why do you need rush trays? And why are there so many? Why is your customer’s patient waiting in the lobby for her RX? Is it possible that “less than ideal work flow conditions” may be contributing factors to why you don’t have good answers for these questions?

Some indications of less than stellar work flow conditions:

• Your WIP is somewhere between four days worth of average production and the Bush Administration’s Budget

• LMS reports have changed the average turn around time increments to display in weeks instead of days

• PA announcements instructing everyone to hunt for a particular tray never stop

• More rush job trays in production than standard trays

• Customer patients in the lobby, eating lunch… again

• You ran out of “Monday Colored Trays” three weeks ago

For such a “Hate to Wait” society, we certainly do it a lot. We have workflow problems everywhere in the civilized world. You don’t have to stray far from your lab to see that you are not alone with your efforts to overcome workflow problems. Workflow issues in the optical laboratory can be divided into four major areas: bottlenecks in production; routing inefficiencies; breakage and re-work; and poor lab layout.


Living in Southern California, my daily dose of horrible workflow is the freeway system. Anyone who has driven in Orange County certainly knows of the “Orange Crush”—the nightmare Los Angeles freeway system where the 405 and 5 merge together, squishing 12 traffic lanes into eight. Most labs have at least one Orange Crush—and it’s easy to spot: it’s generally the area that looks like downtown Manhattan because of giant tray stacks cocooning some poor machine operator. A general rule of thumb: if you can’t see the work station, the staging table, or a machine, but you know it’s supposed to be there, you might have a bottleneck.

Many bottlenecks can be easily addressed with inexpensive solutions that simply take some planning.

• Stagger operators’ breaks and lunches

• Minimize machine downtime through redundancy and the stocking of an adequate supply of spare parts supply. Contact your equipment supplier to get a list of suggested spares.

• Implement an effective preventive maintenance program. Start with training from your suppliers and monitor whether or not the prescribed PM is really being done by using a good preventive maintenance software program or something as simple as a schedule and check-off sheet attached to each piece of equipment using a chained clip board.

• Alternate manual machines after automated machines

• Proper staffing during rush periods—investigate later start times for some employees, especially in AR department.

• “Floating” existing labor from different production areas to the bottleneck areas. For example, nearly every lab that has in-house AR finds that there is a certain period of the day when there is a huge concentration of jobs entering the clean room in need of hand cleaning (to remove markings), inspection and basket loading. Planning for this and scheduling a few extra operators into the clean room during that period each day can greatly reduce the bottleneck associated with the AR batching process.

Some bottlenecks are addressed by adding horsepower to that production stage. This is where operating budget comes in to play. Overcoming bottlenecks usually require capital or additional overhead—so you need to plan carefully.


Another example of an industry with workflow problems bigger than yours is the aviation industry. There are tens of thousands of aircraft commuting across our country at any given time, all of which are departing and arriving on the same 75 foot wide strip of concrete in each major city. NASA has proposed a sophisticated routing solution to be implemented over the next 20 years—a central computer system predetermines the most efficient route a plane should take based on predictive traffic flow calculations. All of this engineering is a preemptive approach to improve future delays related to traffic flow chaos.

This air traffic control problem is more similar to your workflow problem than you might expect. No two jobs you produce are exactly the same. Even though they begin and end their production cycle in the same part of your building, each one can, and does, require different routings through the production process.

One of the more popular new solutions is the utilization of routing conveyors. Smart conveyors are available now and you might be surprised at their affordability. Also, as a tray-color-obsessed-industry, you should be happy to note that the least expensive tray routing decision can be made with a small electronic color sensor


It’s obvious, but let’s just say it…rework is non-conducive to good workflow and breakage spikes kill good workflow. So how do you minimize these kill joys?

• Implement effective process management—hourly/daily calibrations, scheduled quality checks, check-off sheets for specification monitoring, and periodic process audits by outside suppliers or consultants

• Scheduled tool replacements based on number of processed lenses or time

• Statistical analysis of each station and each operator

• Implementation of a rigid training program including training by outside suppliers

• Invest in the best possible supplies and consumables (and have them available when needed!)

Poor Lab Layout and general work flow challenges

Some production delays can’t be attributed to any one obvious issue—rather it’s a build-up of several items that need to be consistently monitored and addressed. Look around your lab… Creating a good consistent workflow through your lab reduces your average delivery time, improves overall efficiency, and reduces manufacturing costs per job.

Tips for improving workflow:

1. Stop paying your people to stack, un-stack, and carry trays. It’s a waste of good labor. If you must stack, limit stacks to 5 trays.

2. Know the real-world capacity of each of your primary work station in Jobs/Hr

• Compare it to all preceding and following stations

• Evaluate it for potential rush hour bottleneck.

• Periodically check real world cycle times of the primary workstations.

• Operators don’t always complain that equipment is running slow.

3. Know the real world requirement of your primary workstations in Jobs/Hr.

• Average Job/Day, Divided by 7Hrs. Times 1.5 = Minimum Production Capacity Requirement

• Average Jobs/Day, Divided by 7 Hrs. Times 2.0 = Rush Hour Conducive Production Capacity Requirement.

4. Start with a good layout

• A bad layout kills workflow

• Distance between workstations dictates whether you have good linear workflow or batched & stacked interrupted work flow.

• Don’t spread out production just because you have the space. The cost is more labor hours and longer average delivery times.

5. Convey the work where and when it makes sense

• Conveyors are not always practical. KISS is appropriate here

• Poorly designed conveyors block access and there are many other potential pitfalls, so utilize the services of an automation company.

• Pay attention to chain speed when using for cooling work.

• Pay attention to distance when using for tray accumulation.

• Know Jobs/Hr of pushing work stations

• Know Jobs/Hr of Pulling work Stations

Imagine a world with no lines, highways with no traffic, and your lab without giant stacks of stagnant work trays. It’s possible. It’s simply a matter of taking an engineering approach at improving and managing the way trays flow through your building.

Steele Young is the Satisloh Territory Sales Coordinator for the Western and Southwestern Divisions.


Labtalk June 2020