The first time a maintenance technician asked me what evidence qualified as an infestation, it didn’t immediately strike me as difficult to answer. But as I paused to go through the Rolodex of pests in my brain, I realized that I couldn’t answer his question with confidence.
My first thought was, “An infestation is a breeding population of insects.” Adult male and female pests with access to food, water, and a place to hide that could find each other and make babies.
But the scientist in me tends to complicate these simple matters by asking questions. What if there is one viable cockroach egg case containing over 30 eggs? If those eggs hatch in the right location, the nymphs could grow to adults and breed. What if there are two bed bug eggs? Those could be a male and a female that could reach adulthood. But the reality of one couple starting what we think of as an infestation is… We don’t really know for a lot of pests. What about one mouse? What if it’s a pregnant female? How would you know from the furry blur that runs along the wall? I could keep going…
Integrated pest management programs can often avoid this difficult topic by setting action thresholds—the number of live pests or certain set of evidence that warrants further action. In agricultural settings, the action threshold is often based on the amount of damage done to the crop. Maryland Department of Agriculture's publication details action thresholds for various pests in schools (which are similar to housing buildings).
In both schools and housing, our tolerance is low when it comes to public health pests. For these pests, we take some sort of action (not necessarily chemical) when one live pest is seen. One cockroach can produce enough allergens to trigger an asthma attack in a sensitive individual. We scale the response to the level of infestation. There’s that “infestation” word again…
Defining what an infestation is can be a fun science discussion. But if you’re a housing inspector or preparing for a Real Estate Assessment Center (REAC) inspection, you need an answer. I was recently informed that there is one for cockroaches and I wanted to make sure everyone was aware of the change.
Effective September 4, 2012, the REAC definition of “Infestation” is clarified with regards to roaches:
“When either one dead roach or only roach droppings is observed in a Unit or in an inspectable item location in Common Areas (e.g., halls/corridor/stairs, laundry room, lobby office etc.), the inspector is to record this observation as Health and Safety, Hazards, Other, and in the comment field write either ‘One dead roach’ or ‘Roach droppings only.’
When more than one dead roach is observed in a Unit or in an inspectable item location in Common Areas (e.g., halls/corridor/stairs, laundry room. lobby office, etc.), the inspector is to record this observation as ‘Infestation.’
When the inspector observes one or more live roaches in a Unit or in an inspectable item location in Common Areas (e.g., halls/corridor/stairs, laundry room. lobby office, etc.), the inspector is to record this observation as ‘Infestation.’
Revision #1, effective September 4, 2012, is a new provision and will be added to Part II: Definition Clarifications, Page 33, Health and Safety, as a new Item ‘E. Infestation.’ The Index will be updated accordingly.”
These revisions are to supplement the existing Uniform Physical Condition Standards (UPCS) guidance which can be found in the Physical Inspector’s Field Guide:
[Images used with permission from American Property Consultants, Inc.]
Other notices that are applicable to housing and pertinent to pest control are:
- Promotion of IPM as an environmentally-sound, and effective means to address a major resident concern
- HUD Office of Housing's Notice on Bed Bugs
- HUD Office of Public and Indian Housing Notice on Bed Bugs