Best Practices for Ventilation in the Workplace

As well as other control measures to reduce infection transmission, like social distancing, keeping your workplace clean and frequent handwashing, the pandemic has highlighted the need for improved ventilation and air quality in indoor spaces. Following HSE’s guidelines, we’ve put together a guide to help you maintain safe, healthy indoor air quality during COVID-19 and beyond.

This guidance will apply in most workplaces – it will help you and your workers:

• Assess the risk from aerosol transmission in enclosed areas.
• Identify poorly ventilated areas.
• Decide on the steps you can take to improve ventilation.

Why fresh air (ventilation) is important

When a person has an infection, they release viral aerosols which can linger in the air for several hours. Having the correct engineered controls in place, such as ventilation, can reduce the risk of airborne transmission and exposure time.

How can I maximise ventilation?

Adequate ventilation dilutes the concentration of viral aerosols in the air and reduces the risk of airborne transmission for anyone in that area.

Maximising ventilation can be done by:

• Increasing natural ventilation like opening windows, doors and air vents.
• Utilising mechanical ventilation such as fans and ducting in the air from the outside.
• Using a combination of natural and mechanical ventilation, for example where mechanical relies on natural ventilation to maximise fresh air.

Natural ventilation

All buildings are designed to provide ventilation, which could be through windows, doors and air vents. You can improve natural ventilation by opening or partially opening these (except fire doors) when people are using or occupying the area. If they cannot be opened, the natural ventilation in that area will be affected.

Purging (airing rooms)

You can air out rooms by opening all windows and doors to improve ventilation. This is best done when a room is unoccupied, especially in colder months.

Mechanical Ventilation

Where possible, it’s recommended to increase the amount of outside air by using existing HVAC systems. Bringing in fresh air can decrease the portion of potentially contaminated air recirculated through your environment, which may help reduce the spread of the virus. The difficulty arises when adding outside air increases demand on HVAC systems to more than they’re designed to handle. You may need supplemental cooling, heating or filtration units to improve air quality and keep occupants comfortable.

Portable HVAC

Affordable, temporary heating or cooling solutions can help you maintain temperatures at a suitable level while moving more air through your structure. Compared to a building’s existing system, portable air con units have more control over the safest placement within a room and can direct airflow away from occupants.

Portable Filtration and Air Cleaning

Although increasing filtration is critical, some older HVAC systems don’t have room for larger, thicker filters, so they can’t be installed in the permanent system. Short-term solutions from Sunbelt Rentals will enable you to use filters with higher MERV ratings until you can overhaul your permanent system. We can also design and implement a HEPA filtration strategy for a room or an entire building. Air scrubbers take in air and run it through a pre-filter, HEPA filter, and post-filter to remove 99.9999% of contaminants. Then, the system pushes clean air into space where it’s needed.

Talking to your workers about improving ventilation

Introducing measures to improve ventilation in your environment is just the first step. To be effective, all occupants must understand the reason for adequate ventilation so that they can play their part in reducing the risk. Speak to them about how they can help.

Conducting a Risk Assessment

Some quick ways of reducing the risk of aerosol transmission include:

• Ensuring any infected persons, or persons with symptoms do not enter the workplace
• Providing adequate fresh air and ventilation
• Restricting the number of people in an area
• Limiting aerosol-generating activities such as singing, physical exertion and shouting

However, each environment comes with unique requirements for ventilation, depending on factors such as size, occupants, layout. It’s useful to conduct your own risk assessment of all indoor spaces and how they are ventilated. For this, you may consider:

1. How many people occupy the area?

More people sharing an environment increases the risk of exposure to aerosol transmission and the presence of an infected person. Can you limit the number of people?

2. How much time do people spend in the area?

The longer people use or occupy an area, the greater the risk. Can you reduce this in any way?

3. How large is the area?

The concentration of aerosols is lower in larger areas as they have more air to dilute airborne viruses and tend to be designed with better ventilation systems. The larger the area, the lower the risk.

4. What activities/tasks are completed in this area?

The deeper you breathe, the more aerosols you generate and the greater the risk of infection transmission. If possible, limit and adapt activities that lead to deeper breathing, such as exertion or shouting. This could be as simple as moving these activities outside or working alone.

5. Are there any features that affect ventilation?

Do you have large machinery or equipment that would prevent air circulating? This could create stagnant parts of the area.

6. Do you use any desk or ceiling fans?

Desk or ceiling fans should not be used in poorly ventilated areas.

7. Does your workplace use local exhaust ventilation?

Your business may use local exhaust ventilation (LEV) to control risks from other workplace hazards such as dust or welding fumes. If these discharge the air outside, they will increase ventilation in the area.

8. Is there a complex ventilation system?

Certain types of environments, such as older buildings, may have more complex ventilation systems. You may need to seek guidance from a ventilation specialist.

How can Sunbelt Rentals help?

Our highly trained team works with you to design efficient, eco-friendly and cost-effective cooling air quality management solutions suited to your environment.

Contact a member of our Climate Control team today on 0800 630 0472 or climatecontrol@sunbeltrentals.co.uk.