Ben Walker principal consultant for ManageMen, Inc and Janitor University

When I was a senior in high school, I took Probability and Statistics for my math class, instead of Calculus. I thought it would be an easy alternative that would further my ambitions of slacking off during my senior year. At the same time, my father, John Walker, was working on the 310 Cleaning Times book.

One day, he tapped me on the shoulder and said he had a job for me. He knew that I needed of a final project for stats class, and he was in need of a formula for predicting cleaning times in square feet per hour. What I didn’t realize at the time is that project would stick with me for the rest of my career.

Cleaning times and tasks are among the most misinterpreted data sets in the industry — many times misapplied, used to make inaccurate comparisons, or misused altogether. But there’s no magic to understanding cleaning times.

It’s important for you, the cleaning manager, to understand how to perform your own time and motion studies.

You don’t need to hire an expert, or even be one, to determine your own cleaning times. In fact, there’s a simple recipe for performing a time/motion study. You’ll need: an open, 1,000-square-foot space (or a fixture count, if working with restroom tasks); a tape measure; painter’s tape; a stopwatch or video camera (I prefer the latter, as it helps mitigate any disputes); if possible, three different people to perform the tasks; and the proper tools/equipment to perform the work three to five times.

To get started, take an inventory of cleaning tasks that you’re going to study. I prefer to evaluate single tasks at a time (i.e. vacuuming carpet using a 14-inch upright vacuum) because it’s easier to keep work organized. Instruct your worker to perform the work at a productive, but comfortable pace to cover the entire 1,000-square-foot area. Make note of any variations in methods or motion — they will be useful if you encounter any substantial time discrepancies.

Next, observe and record at least three to five different times per person in your test — people tend to pick up the pace as they become used to their working space. Once these have been completed, record the times in minutes for each trial and then determine an overall average.

Finally, you’ll want to make adjustments for any constant variables (travel speeds, filling times, emptying buckets, etc.) if they apply to the task you’re evaluating.

Once that’s completed, you’ll be ready to convert your cleaning time to an hourly production rate. To do this, follow this formula: 60 divided by your cleaning minutes, times 1,000 square feet, equals hourly production rates (based off a 1,000 square foot test). Once that is completed, apply this square-feet-per-hour to your daily cleanable square footage. With that, you’ve determined your daily production rate. For example, if your cleanable square footage is 30,000, and your production rate is 10,000 square feet per hour, your estimated cleaning time for that task will be about three hours.

But, be aware that there are a couple of caveats. You’ll need to account for obstructions when applying these numbers to your cleanable square footage. Typically, this number is about 55 percent of your facility’s total square footage. If your cleaning workload requires travel over large areas, representative travel speeds can be found in the front section of the 612 Cleaning Times book. I find them to be accurate and dependable when applying them to existing cleaning tasks. 
Ben Walker is the principal consultant for ManageMen, Inc., a cleaning industry consultancy specializing in management advisement and education. He is an instructor at Janitor University and author/co-author of several industry publications.