Clean air in museums

Wednesday - 28 August 2019

The World Health Organization rank air pollution as the greatest environmental threat to mankind, with seven million deaths a year attributed to breathing polluted air.1 Governments around the world are making efforts to clean up the air in their cities, but poor air quality is a fact of life for millions of people, and will continue to be for the foreseeable future.

But air pollution isn't just a risk to human and animal life. Airborne contaminants can tarnish metals, damage leather and erode textiles. So, while museums, art galleries and other cultural institutions must take steps to preserve the health of the people in their buildings, they also need to protect artifacts and exhibits from the damaging effects of air pollution too.

Protecting exhibits

Most museums and galleries will limit how much and for how long an exhibit is exposed to both natural and artificial light sources. Temperature and humidity will also be closely regulated to prevent damage to artifacts and exhibits. But just as important is ensuring the quality of air. Air pollution is harder to identify than light, temperature or humidity issues, so can often go unnoticed. But even at low levels, gaseous and solid contaminants can cause irreparable damage to entire collections – taking a cumulative toll on exhibits that have been around for hundreds, if not thousands of years.

Acidic contaminants

Museums and art galleries are usually located in city centers, with high passing footfall and good transport links. But being located in urban environments means that these institutions are particularly at risk from sulfur dioxide and nitrogen dioxide. These contaminants – generated by the burning of fuel in vehicles, power generation and industrial applications – react with other substances, such as water, to form acidic compounds that attack organic materials and cause permanent damage. Limestone and marble can dissolve and discolor, metals can corrode, leather can become brittle, and textiles and paper items can weaken and fade.

Oxidizing contaminants

Some contaminants are generated indoors and are equally as dangerous. When nitrogen dioxide reacts with sunlight, it forms ozone, which causes oxidation reactions with various organic and inorganic materials. This can cause dyes and pigments to fade, rubber and plastics to crack, metals to tarnish, and textiles to become brittle.

Volatile organic compounds (VOCs)

Paints, cleaning products, adhesives, and other products commonly found internally emit VOCs, such as formaldehyde, into indoor environments. Some display cabinets can have particularly high levels of VOCs due to the adhesives and sealants used in their construction. So, while the protective glass may protect the exhibit from acidic or oxidizing contaminants, items such as photographs, metal objects and certain types of glass can still be at risk of permanent damage.

Particulate matter

Particulates may not cause any acidic or oxidation damage by themselves, but they can react with gaseous contaminants, such as sulfur dioxide, to cause corrosion and fungal growth. Particulates also cause soiling, which poses a potential threat to exhibits during cleaning, and also promotes the growth of mold, bacteria and fungal spores. Salt particles can also accelerate corrosion in metals and are a particular problem for museums and galleries in coastal locations.


Protecting People

92% of the World’s population breathe unsafe air2, which has elevated air pollution to the fourth highest risk of death3. Scientists have linked the inhalation of particulates with a myriad of health complaints, ranging from asthma and inflammation of the respiratory system to heart disease and various forms of cancer.

As awareness of air pollution increases amongst the general public, so too does the expectation that public buildings will be safe places to spend time, away from the dangers of air pollution. But, as pollution levels are typically two to five times higher than those found outside, this is not always the case. Forward-thinking building owners and operators recognize that providing a safe, clean indoor environment is not only a responsible thing to do, it can also make commercial sense too – with people choosing to visit buildings with good air quality more frequently and for longer periods.

It also makes sense from a productivity aspect too, with numerous studies showing that good indoor air quality reduces sickness and staff absence, while boosting output and decision making.


What can you do?

Many museums, galleries and other cultural institutions will already have an extensive air filtration system in place. But there are still some actions that you can take to ensure that it is performing to its very best level.

Think about removing a gas filter stage

Gas adsorption filters are well proven in museum settings. These filters adsorb gaseous compounds with a media impregnated with activated carbon. Acidic and oxidizing contaminants along with VOCs are captured and removed from the air flow, before they have a chance to damage precious or priceless assets.

If you already have a gas adsorption stage in your building, the idea of removing it may seem counterintuitive. But new combined particle filtration and gas adsorption filters offer performance that is close to that of separate filter elements for each function. And that means you can access significant cost reductions by removing a filter stage.

The pressure drop of an air filter system is a cumulative total of all its stages. Remove a stage and the overall pressure drop – and so, energy demand – will reduce significantly. Switching to combined particle and gas adsorption filters will also mean you have fewer filters to purchase, store, fit and throw away.

If you do not currently have a gas filter stage in your system, combined particle and activated carbon filters make it easy to integrate this capability into your air handling unit. Simply swap your existing particle filters for combined filters with no need to retrofit your HVAC system.

Review your system performance regularly

When it’s time to change, air filters are typically replaced like-for-like, or with what’s similar and in-stock. The problem with this approach is that it does not account for changes in the surrounding environment. Increases in traffic levels or patterns, local construction activity or new industrial buildings nearby can all contribute to changing the type and level of pollutants entering an HVAC system.

If it has been a while since your air handling system was last inspected, ask your filtration partner to conduct a review of your facility. This should include an air quality survey with numerous measurements taken inside and outside of your building. This evidence should then form the basis of a customized filtration solution that is tailored to your exact requirements.

As pollutants can vary massively from room to room, the air filtration system should be verified for performance after installation. Museums and galleries hold our more cherished items. It’s imperative that the filtration system is up to the job of protecting them.

Learn more about the eco16 filter management program that guarantees you safe air quality at the lowest possible cost.


1 World Health Organization, 7 Million Premature Deaths Annually Linked to Air Pollution, March 2014

2 World Health Organization, WHO releases country estimates on air pollution exposure and health impact, September 2016.

3 BBC, Polluted air causes 5.5 million deaths a year new research says, February 2016