Activity Analysis 101: Comparison to Work Sampling and Lean Six Sigma

Article written by PER Senior Consultant, Daniel Galeano.

Activity Analysis 101: A Quick Overview

This article provides an overview of the Activity Analysis methodology, including topics ranging from application, origins, similarities with Lean Six Sigma, differences from Work Sampling, expected results, and its future.

What is Activity Analysis?

According to the Construction Industry Institute, Activity Analysis is a continuous process of measuring and improving the amount of time that craft workers spend on actual construction. This measured time is referred to as tool time, wrench time, or direct work time [1]. Activity Analysis can also be described as a continuous improvement effort based on an on-site field analysis of how craft worker efforts are being utilized by management.

The base unit of data used for measurement is an observation. An observation is a split-second analysis or snapshot judgment of an activity being performed. The Activity Analysis method observes different activities occurring in the field and classifies them based on the activity’s relationship to advancing schedule. It can be implemented in-house or by a third-party.

Figure 1. Activity Analysis Snapshot Representation – Direct Activity, Safety Watch, and Internal Delay

Where can Activity Analysis be used?

The Activity Analysis methodology can be applied to several fields. Activity Analysis has already been applied in numerous settings (e.g. Fabrication Yards, Hydroelectric Dams, Refineries, Nuclear Plants, Fossil Plants, and Terminals) and multiple industries (e.g. Chemicals, Construction, Engineering, Mining, Oil & Gas, Utilities, and Shipping). Activity Analysis can be applied to any field with labor intensive processes, where labor is a large component of total installed cost (TIC), where schedule duration needs to be managed closely (i.e. Turnarounds, Outages), or where there are monetary responsibilities to fulfill (e.g. investors expecting revenue streams).

What are the origins of the Activity Analysis methodology?

The building block of the Activity Analysis methodology was the “Snap Reading Method”, which is an Industrial Engineering technique born in 1927 [1]. This method consisted on observing activities performed and classifying them in one of two categories: production or delay.

The next iteration was called Work Sampling and it provided a more in-depth classification of activities performed, typically breaking down observations into three main categories: direct, support, and delay.

Activity Analysis builds upon Work Sampling and breaks down those three main categories into additional subsets.

Figure 2. Comparison between basic Snap Reading, Work Sampling, and Activity Analysis charts

How is Activity Analysis different from Work Sampling?

Even though Work Sampling and Activity Analysis are sometimes used interchangeably, there are a few differences that should be kept in mind. The following differences listed borrows and expands on main themes from the Construction Industry Institute [1]:

• More Activity Classifications: Activity Analysis expands from Work Sampling’s activity classifications and incorporates more definitions during observations.
• More Observation Metadata: While most Work Sampling efforts where focused on the activity category, Activity Analysis expands on the amount of metadata collected with each observation activity. This difference allows for additional analyses and other considerations.
• Continuous Improvement Focus: Activity Analysis is typically geared towards continuous improvement, whereas Work Sampling was not.
• Data Collection Methods: Activity Analysis has benefitted from digital data collection, while Work Sampling relied mostly on manual data entry.

One way to think about the difference between the two could be simply looking at the names. It could be said that Work Sampling focuses more on work as a whole and less on individual activities, while Activity Analysis focuses on activities as the main subject and work as an aggregate.

What are some of the similarities between Activity Analysis and Lean Six Sigma?

Activity Analysis methodologies can implement the DMAIC problem-solving methodology which is also used by Lean Six Sigma

• Define: Identify areas that will be analyzed for the study
• Measure: Capture observations or perform Activity Analysis
• Analyze: Using the collected data, create valuable metrics
• Improve: Based on findings, target opportunities for improvement
• Control: Using continuous improvement, track improvement efforts and set goals. Perform follow-up assessments to validate improvement and target the latest opportunities.

Activity Analysis also shares the Lean Six Sigma focus on maximizing value-added activities and reducing or eliminating non-value-added events. The idea behind Activity Analysis targets doing more with less to work smarter, not harder.

Figure 3. DMAIC Process used by Lean Six Sigma and Activity Analysis

What are the main benefits of Activity Analysis?

One of the main strengths of Activity Analysis is bridging the gap between management and front-line personnel, as data collected in real time reflect current events in field performance allowing for timely analysis. This is powerful information that can be leveraged by stakeholders, especially when coupled with other traditional metrics.

Another key benefit is the possibility of developing and escalating continuous improvement goals through the integration of Activity Analysis with management efforts.

How long should an Activity Analysis effort last?

To put it simply, this is largely up to the owner of the study. A longer effort will result in the capability of providing more insights and trends over time on multiple data layers, with a better chance of obtaining more opportunities for improvement. On-going or multiple Activity Analysis efforts are also highly beneficial when the goal is to achieve continuous improvement. The minimum duration should allow for proper sampling levels to the captured, from a statistical perspective.

What type of information can Activity Analysis provide?

Data collected during an Activity Analysis has multiple attributes, therefore there are multiple metrics available when slicing and dicing through the data.

The most popular metric is the time that craft workers are available at their workface or labor availability, which is usually referred to as “time on tools”, “wrench time”, or “direct activity”. This is a very powerful metric to know because it provides management with an idea of the current system capability to advance schedule.

One of the latest developments in Activity Analysis metrics is the assessment of Foreman Availability. The objective is to assess what percentage of available productive time do the project's foremen spend at the workface with their crews. There is a direct correlation between increased availability and improved productivity, safety and quality performance. Intuitively, this dynamic is driven by leveraging the leadership skills of the project's foremen where it counts, physically with their crews.

Activity Analysis also provides insights into the major delays removing time from workers, as well as the current levels of effort required to perform supportive tasks, such as Empty Travel, Travel with Tools and Equipment, or Travel with Materials.

Since Activity Analysis observations are collected several times per shift over a few weeks, statistically significant break downs can be performed on different data sets such as craft types, areas, contractors, hours, location, to name a few.

Figure 4. Basic chart examples provided by Activity Analysis

How can I use information obtained through Activity Analysis?

Information obtained through Activity Analysis can give management an idea of how their “game plan” is manifesting in the field and/or what are the main obstacles impacting performance.

Activity Analysis information can be used to develop and validate best practices to replicate successes in future endeavors. It can also be compared with project controls information to see where efficient and effective craft utilization performance diverge, making it easier to identify root causes of deteriorating performance.

Using information gleaned from tools like the Pareto Principle, Activity Analysis can assist to target efforts on the “significant few”.

Activity Analysis information typically reflects impacts caused by processes and current support systems (e.g. tool rooms, rest areas, material delivery) in place and can be another avenue to make informed decisions concerning changes.

What is the future of Activity Analysis?

To understand the future, one can look at the past. The next iteration of Activity Analysis will most likely expand on the amount and type of data being collected as well as exploiting new technologies. Some of the technologies with the most potential include RFID and GPS tracking of craft and equipment movement, artificial intelligence, machine learning, and virtual/augmented reality. Stay Tuned.

References:

[1] Construction Industry Institute, IR252-2a — Guide to Activity Analysis, Jul. 2010