Environment Health and Safety Practice Area Leader and Principal
As workplaces open again under COVID-19 guidelines, companies and businesses need to consider another potential risk for employees who are re-entering vacated workplaces – Legionnaire’s Disease. This is a severe form of pneumonia, with some symptoms similar to COVID-19, and is spread through inhalation of droplets and aerosols containing microscopic organisms, in this case Legionella bacteria. Underlying conditions or lingering effects from a COVID-19 infection can increase the vulnerability and severity of response for an individual in contact with Legionella bacteria.
The bad news is that Legionnaire’s Disease is potentially debilitating or even deadly for vulnerable populations. The good news is that it can be prevented with good building management practice.
How does it spread?
Protecting employees, tenants, visitors, and other building users from Legionnaire’s Disease starts by understanding how it occurs. Unlike COVID-19, people are not the source. It is not spread by coughing, sneezing, drinking, eating or surface contact. Legionella is spread from water that sprays out of faucets, shower heads and other nozzles. As an aerosol, that bacteria-containing water gets breathed in by people close to the spray, and Legionella enters their lungs. While many people’s immune systems can easily shrug off the bacterial invasion, this may not be true for people who are older or immune-compromised. Most distressingly, people whose lungs have been impacted by COVID-19 appear to be particularly vulnerable to Legionnaire’s Disease.
Where is it found?
Legionella lives in water – particularly stagnant water found in plumbing systems – especially showers, ice machines, indoor water features, and rooftop cooling towers. Normally, when buildings are occupied, plenty of water flows through these systems, and Legionella gets flushed out before it can accumulate. Regular maintenance and disinfection – particularly on cooling towers – also keeps Legionella from amplifying.
In a building that has been shut down for weeks or months due a global pandemic, there is an excellent chance for Legionella to accumulate. Relying on disinfectant levels that are added by municipal waterworks to control bacteria will not be enough to control Legionella or prevent it from growing, especially when the water has been sitting in pipes for extended duration. If Legionella has concentrated to the point that the spray from a faucet results in dangerous exposure scenario for a building’s occupants, this could lead to a rise of Legionnaire’s Disease at a time when our public health system is already stressed.
Why maintenance matters
Standard operation of a vacant or partly vacant building calls for flushing water systems regularly, perhaps on a weekly basis. This would require a small building management staff – perhaps just a skeleton crew — going through the building each week, turning on every faucet for several minutes, flushing every toilet and urinal. Still, even with best efforts, the flushing may not have been done to a level required to keep the water in the pipes fresh.
Another aspect of the post-COVID-19 return to workplaces is that the return is likely to be gradual, sporadic, and partial. With many people choosing to continue to work from home, the pre-COVID-19 population and volume of water use, will not be same as it was prior to quarantine. There may also be vast areas of the workplace that remain vacant, leaving many sections of a building with stagnant water in pipes, giving Legionella a chance to concentrate. In this scenario, someone walking through a deserted part of the building who pauses for a drink of water could be putting themselves at risk.
Another risk factor comes from the way building water systems have been designed, or rather evolved. Buildings are constantly being changed to meet new purposes which often means changes to plumbing systems. One side effect of this is that there are often redundant pipes — or dead sections of pipe — where the water just sits. Unless all unused piping has been removed or sealed off, there is a chance that Legionella can develop even in a building with a normal level of activity.
7 steps building owners and managers can take
Whether your building has been idle a week or a few months, there are steps to take to protect your location – and the people who use it — from being impacted by Legionnaire’s Disease:
- Learn what has been done already: Ask for records of what the building management crew has done in terms of flushing the system, to see if it is sufficient to keep returning workers safe.
- Follow recommended best practices: Organizations such as the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) have established best practices and guidelines for reopening of buildings. While these do not have the force of law, they do provide an idea of best practice. Following these guidelines can help an employer demonstrate due diligence in a situation in which someone using the building falls ill from Legionnaire’s Disease.
- Take responsibility for your own water systems: Remember that the overall building management is responsible for flushing the systems of the building itself. However, each tenant is responsible for maintaining its own systems – such as putting each ice machine through its paces, changing filters on water coolers and coffee machines, and running an empty dishwasher load in each kitchen. And, just in case, be sure to flush the building’s systems in your part of the building thoroughly. A Legionella testing and sampling plan can help you detect potential problems.
- Set up a water management plan: It is important to set up a plan for keeping pipes and fixtures flushed, particularly if the workforce coming back to the workplace is much reduced from the one working in the space pre-COVID-19. This should be a regular part of the ongoing maintenance plan.
- Take care of vulnerable populations: Consider encouraging anyone who is potentially at risk in the workplace to continue working from home. This includes anyone over 65, with any underlying medical condition that might make them immune-compromised, and anyone who has tested positive for COVID-19.
- Take “re-commissioning” seriously: When a new building is first occupied, there is a formal commissioning process. Think of your reentry to the workplace as a “re-commissioning” of the space. A big part of this is checking and flushing out anything that involves water.
- Inform tenants of protection measures: Many employees will be concerned about returning to the workplace and may not be as productive as they could be while there. Notify them that you are taking the necessary steps to protect them from COVID-19, but also other potential risks such as Legionnaire’s Disease.
With these measures in place your return to the workplace has a better chance of happening smoothly, and you will be protecting employees from the dangers of a disease many would not think to associate with COVID-19.