Keeping the lab lean

Introducing Lean Principles into the Laboratory can increase speed, efficiency and quality says Dr Michael Allen

 “LEAN” has been a popular method of process Improvement since Womack and Jones first published in 1991 The Machine That Changed The World, their analysis of the Toyota Production System. They described how a Lean organisation would progressively identify and eliminate waste - a Lean process essentially produces just what the customer wants, when the customer wants it and to the quality and cost that the customer expects. A Lean organisation also appreciates that competition is always increasing – and so improvement must be continuous.

Though Lean started in a purely manufacturing environment many of the principles apply outside of manufacturing. Here we look at how some key Lean principles may be applied to a laboratory.

Lean principles can aid a laboratory in significantly increasing speed, efficiency and quality. A key teaching in Lean thinking is that physical layout will affect how people work - physically separating process steps creates “hand-over points” – this can lead to increased batching of work and delays at the hand-over points, both of which can significantly increase the turnaround time of work (and therefore delays in delivering to the customer). In a Lean lab thought is given to ensure that as many process steps are conducted as closely to each other as possible – preferably within just a few steps. This naturally encourages flow of work from one process step to the next with minimal batching and hand-over points. It may be expected that up to 50-75% of turnaround time may be eliminated simply by adopting a Lean-layout which supports the flow of work.

Visiting laboratories reveals that many labs are full of a myriad of lab supplies, some that have not been used in months or maybe even years. Looking at how much of your lab space is being used for storage is an important step in increasing the efficiency of how lab space is being used. By good laboratory organisation (that is sustained) coupled to an effective supply system which minimises over-ordering, experience shows that 30% or more of your lab space could be freed up for more productive use. Lean provides a framework (usually called “5S”) for ensuring that once a workplace has been organised it stays organised and clutter-free. Quality may be increased by tighter control on storage and use of laboratory consumables (ensuring consumables are used when fresh).

Laboratories are rarely like manufacturing plants – in laboratories there is usually a much greater variety of small scale equipment that is used sporadically. Manufacturing techniques for increasing equipment efficiency may therefore be inappropriate for laboratory equipment. Some key principles still apply however – in a Lean lab the breakdown and repair of equipment should be accurately tracked (for example, consider having T-cards on all equipment that are recorded with the fault and the repair). This information may be used to improve end-user maintenance of equipment, negotiate appropriate service and repair contracts, recognise when equipment is reaching the end of its useful life and understand which equipment is most or least reliable. A good understanding of equipment performance is likely to lead to significant savings in repair, maintenance, and replacement costs as well as improving equipment reliability and subsequent data quality.

Two key Lean principles can aid in significantly reducing turnaround times in laboratories – value stream mapping and work in progress control.

“Value stream mapping” follows a process from beginning to end and identifies each step as adding value or not adding value (at Toyota, Taiichi Ohno described seven key non-value adding wastes to watch out for, and which may also be used when examining work flow in laboratories. These are: transport of goods, inventory storage, movement of people, waiting, over-production, over-processing and defects). In many processes storage and waiting steps account for more than 90% of the turnaround time that the customer experiences. In these cases turnaround time may be significantly improved not by improving the process steps themselves, but by creating much better flow within the process – tying process steps closer together. A value stream map helps those working in the process to identify where the key waste is in the process (when a process runs across different people or teams many of the delays may not be obvious to the people involved). The process may then be steadily modified to eliminate the delays in the system -which is often helped by considering the existing physical layout.

A second key Lean principle is to understand the level of work that is ongoing at any one time – the “work in progress” (or “WIP”). Turnaround times increase in proportion to the amount of WIP (this is “Little’s law”). There are some simple methods for controlling WIP and therefore reducing turnaround time. For example “completion priority” (where resource is always moved to work that is at a later stage rather than starting new work) naturally pulls WIP out of the system and can reduce turnaround times by 50%. WIP and turnaround times also tend to increase very substantially when throughput exceeds about 75% total capacity. It is important that a laboratory is resourced at a suitable level. One needs to be careful in basing resources on the average level of work going through a lab, and running equipment at more than 75% utilisation.

Any process improvement initiative rests on knowing what is working, and what

“Visiting laboratories reveals that many labs are full of a myriad of lab supplies, some that have not been used in months or maybe even years” “Many key Lean principles are very applicable to laboratories and will increase productivity and quality, and reduce turnaround times and costs”

is not, and being able to recognise whether a change has improved matters or not. Two essential components are standard work and quality monitoring. With standard work effort is applied to ensuring there is minimal variation in how a process (or process step) is performed. The process should be well described (photos and video may provide a useful addition to a SOP) and trained – so that individuals don’t each have their own preferred way of performing a task. If there are differences between how individual perform a process step then experiments may be used to understand the better way. Once a standard has been implemented then key quality indicators (picked to reflect how the customer experiences quality) should be put in place and monitored. A Lean lab will ensure that the quality indicators are obvious to everyone – local visual displays should ensure that any change in quality is immediately apparent to all staff and managers who are involved in the process. Over time statistical measures may be put in place, but the priority to begin with is to ensure that quality is measured and visible to all. Once work has been standardised and good quality measurements put in place then the teams are encouraged to progressively improve the process.

A tool that is increasing in popularity in Lean implementation is process simulation. Process simulation enables a virtual model of a process or laboratory to be created which allows experimentation in a cost-free virtual world, without disruption to ongoing processes. For example equipment or staff may be added (or removed) to study the expected impact. Processes may also be altered or staffing arrangements (such as shift patterns or multi-skill training) changed to understand the potential benefit. While simulation can never totally replace shop-floor process optimisation it can greatly help teams to understand their system, choose the best options and minimise the potential disruption of process redesign.

Care must always be taken when transferring knowledge between different environments – laboratories have both similarities to and differences from manufacturing environments. Many key Lean principles are however very applicable to laboratories and will increase productivity and quality, and reduce turnaround times and costs. Lean thinking can therefore help ensure that laboratory managers get the very best from their facilities.

Dr Michael Allen is a Lean Laboratory Consultant with the Leading Edge Group. He is an experienced expert in the application and training of Lean, Six Sigma and Simulation techniques to laboratory and R&D environments. This is backed up by 20 years experience as a scientist, manager and project leader in the pharmaceutical industry, with experience including working in basic science laboratories, advanced automated facilities, portfolio modelling and clinical study planning.