By Michael Tobias

As an increasing number of businesses open up after the global shutdown necessitated by SARS-CoV-2, the fundamental need to maintain a healthy work environment must be maintained. It is also essential to maintain healthy business operations to ensure that the impact of the virus is minimized. 

The Coronavirus Disease 2019, better known as COVID-19, is a respiratory illness that is spread from person-to-person by droplets or particles that emitted or transmitted when an infected person coughs, sneezes, or even shouts. But the problem is that it is often spread by people who show zero symptoms. For this reason, business owners and employers need to institute controls that will protect their employees as well as members of the public they may come into contact with. 

The US Centers for Disease Control and Prevention (CDC) has identified a traditional hierarchy of controls that may be used to determine how to implement the most feasible and the most effective control solutions in the workplace. This is, however, a traditional methodology, so the CDC and other organizations and bodies including the World Health Organisation (WHO), the US Department of Labor Occupational Safety and Health Administration (OSHA), and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) have issued guidance on best to respond to COVID-19 and minimize its risks in the many varied industries of our economy. 

Traditional Hierarchy of Controls

Irrespective of the deadly coronavirus that has turned our lives upside down, the control of occupational hazards is the fundamental way to protect workers. 

A traditional hierarchy of controls presented by the CDC’s National Institute for Occupational Safety and Health (NIOSH) has five levels:

  1. Elimination, which is the most effective in the hierarchy because it results in physically removing hazards. However, it is the most difficult to implement when processes are already in practice because, to be able to eliminate the problem, it is often necessary to make major changes to procedures and equipment.
  2. Substitution involves replacing hazards and is also a very effective way of controlling and reducing hazards. Like eliminating hazards, it can be difficult and expensive to substitute these. If processes are still in design or development stages it is easier and can be relatively inexpensive to implement. 
  3. Engineering controls are devised to isolate people from hazards. They are generally preferred to administrative or PPE controls because they remove hazards at the source, before those in the workplace are affected or put into a position of risk. Even though engineering controls generally cost more than administrative or PPE controls, operating costs are usually lower and they often lead to cost savings in other areas. 
  4. Administrative controls that are introduced to help improve existing processes. They don’t usually cost much to establish and implement but they can be costly to sustain.  
  5. Personal protective equipment (PPE) certainly has its place in the hierarchy of controls and should be worn as directed. But in the overall scheme of things, the other measures have more impact. They all work well together!

Engineering Controls to Minimize the Risks of COVID-19

NIOSH, which devised the traditional hierarchy (see above), also has a comprehensive resource of engineering and physical hazards reports that recommend and/or provide control solutions for a wide variety of hazards including air contaminants and noise pollution. Additionally, there are a host of other publications available from NIOSH from alerts, fact sheets, and criteria documents, to health hazard evaluations, hazard controls, and specific workplace solutions. Of course, the type of hazard would determine which sphere of engineering services was involved, for instance, heating, ventilation, and air-conditioning (HVAC), electric, plumbing, or mechanical engineering services

Although these documents are as recent as 2019, they don’t relate specifically to the current coronavirus. There is, however, a paper from 2012 that discusses responses to natural and/or manmade epidemics that looks at expedient measures for “surge airborne isolation”. These measures usually involved negative-pressure isolation wards where airborne infectious patients were isolated during the outbreak of diseases like SARS, MERS, Ebola, measles, and highly pathogenic avian influenza. It may, therefore, be relevant to the current pandemic.

While the traditional hierarchy of controls and existing research is useful, the CDC has responded with strategies and a series of recommendations that businesses and employers are encouraged to use to help resume business operations. These incorporate the need for daily health checks, hazard assessments of the workplace, the use of cloth face masks/coverings in appropriate situations, and social distancing. Additionally, there is important guidance on how to improve building ventilation systems. 

Engineering controls that use the ventilation systems in buildings include:

  • Increasing the rate of ventilation.
  • Ensuring ventilation systems work appropriately by providing indoor air that is of an acceptable quality.
  • Increasing outdoor ventilation but taking care to ensure that there is sufficient fresh air if outdoor air is polluted.
  • Disabling demand-controlled ventilation. 
  • Improving air filters to MERV 13 or higher.
  • Checking filters and ensuring they are properly installed and within service life. 
  • Keeping systems running for longer – if possible 24/7, to increase the quality of air exchange within the building spaces.

To ensure your building isn’t either a high risk or has the potential to become a high-risk area for coronavirus infection, commission an indoor air quality HVAC report from an engineering firm that has the capacity to identify the very best prevention measures. They will be able to reconfigure the ventilation system and identify how to improve filtration and purification measures for your HVAC equipment. 

Above all, stay safe and take every possible measure to keep your employees safe too. 

Michael Tobias is the founder and principal of both Nearby Engineers and New York Engineers, an Inc 5000 Fastest Growing Company in America. He leads a team of more than 30 mechanical, electrical, plumbing, and fire protection engineers from the company headquarters in New York City, and has led numerous projects in New York, New Jersey, Chicago, Pennsylvania, Connecticut, Florida, Maryland, and California, as well as Singapore and Malaysia. He specializes in sustainable building technology and is a member of the U.S. Green Building Council.