Breathe easy

It’s ubiquitous, invisible, and seemingly boring — but the quality of the air in a casino can make a significant difference to the well-being of customers and staff, as Barnaby Page reports.

Bad news came twice last year for Caesars from an unexpected and seemingly innocuous source: its Cherokee Casino Resort in North Carolina, and earlier the Laughlin Hotel & Casino in Nevada, were both investigated for suspected outbreaks of Legionnaire’s disease.

The investigations were routine — this severe form of pneumonia is always checked out by health authorities — and the countermeasures well-established: disinfecting water and improving water management to prevent the disease spreading through microscopic droplets, notifying guests who might have been exposed.

But they highlighted a problem that faces all casinos, in common with any large public facilities. Legionnaires’ disease is spread not by individuals, but by the building itself, and it is just one of the more spectacular ways in which management of indoor air quality (IAQ) can have a significant effect on businesses.

Air quality is a broad term; one dictionary defines it as “the degree to which air is suitable or clean enough for humans to remain healthy”. The United States Environmental Protection Agency, an influential authority on the subject, pins it down more precisely as “the quality of the air inside buildings as represented by concentrations of pollutants and thermal (temperature and relative humidity) conditions that affect the health, comfort and performance of occupants”.

Pollutant levels

It’s important because people spend about 90% of their time indoors, where pollutant levels can be as much as five times higher than outdoors, and indeed the recent Air Quality Life Index produced by the University of Chicago identified air pollution as the world’s biggest killer.

And for businesses like casinos, maintaining good air quality is more than just an abstract matter of social responsibility. Poor air quality can affect reputation, customer satisfaction and retention, and employee performance; it can also lead to liability and compliance issues.

Impacts on affected individuals can be both long-term (chronic) and short-term (acute); they can arise from a single exposure to a pollutant, or be the result of long-term exposure. Common short-term symptoms include headaches, sinus congestion, coughs, skin or eye irritation, nausea and fatigue; more serious longer-term issues include cancer — the most common major chronic condition associated with poor IAQ — as well as heart disease and respiratory diseases.

Poor IAQ is usually the primary cause of Sick Building Syndrome (SBS), typified by headaches and respiratory difficulties, particularly in white-collar workers. Other conditions caused by specific factors in the air are often grouped together as building-related illness (BRI); these include hypersensitivity pneumonitis and humidifier fever as well as Legionnaires’.

Linking specific conditions with particular IAQ factors may be difficult, because individuals’ reactions vary, also people are exposed for different periods of time in different parts of the premises, and because some pollutants — for example tobacco smoke — have both acute and chronic effects. If a smoky gaming floor is causing asthmatic customers’ condition to worsen, improved ventilation can quickly solve that problem, but it won’t remedy any long-term effects that prolonged exposure to the secondhand smoke might have had on staff, for example.

Perhaps less well-known is the contribution of IAQ to employee performance. As the EPA puts it: “Significant measurable changes in people’s ability to concentrate or perform mental or physical tasks have been shown to result from modest changes in temperature and relative humidity [and] similar effects are associated with indoor pollution due to lack of ventilation or the presence of pollution sources. Estimates of performance losses from poor indoor air quality for all buildings suggest a 2-4% loss on average.”

Danger lurking everywhere

There’s no single measure of IAQ; the factors influencing it are complex, and they depend on the design of the building and the way it is used, as well as specific pollutants. Effects of IAQ — such as unpleasant odours, stuffy or stale-feeling air, and physical symptoms — clearly indicate that there is a problem, but air quality can also be measured more objectively by collecting samples of air and of particles deposited on surfaces.

Other techniques, such as computerised modelling of air flow and calculation of the frequency with which the air inside a space is replaced, do not in themselves tell you whether or not IAQ is a problem but they can suggest whether it might be.

But why does the problem arise at all — why can air quality be so much worse inside buildings than outside?

Substances used in building materials, decoration and furnishing are a major factor; asbestos is the most famous, but others include formaldehyde (found in particle board, fabrics and furniture) as well as the volatile organic compounds (VOCs) that abound in paints, adhesives and polishes. Tiny particles can in themselves be an issue, for example when they become detached from insulation materials; some of the everyday paraphernalia of business contributes too, for example with VOCs from printers, and particles from paper.

Tobacco smoke is another well-known factor, albeit one that is increasingly under tight control in most jurisdictions, but it is not the only “combustion contaminant” that plays a role; furnaces and generators can also emit harmful by-products.

Then there are the natural and biological factors. Radon, coming from the soil or rock on which a building sits, is a major IAQ issue in North America and Europe. Molds can develop on wet materials, and humidifiers can encourage them. Rodents and dust mites may also contribute to IAQ, as ironically can pesticides.

Exacerbating all these root causes are factors in building design and facilities management. As the EPA observes, “the tendency toward tighter building envelopes and reduced ventilation to save energy, and pressures to defer maintenance and other building services to reduce costs have fostered indoor air quality problems in many buildings”.

Finally, air quality problems from outside can penetrate indoors, including pollutants caused by vehicles or construction work.

Given all this, it’s clear that completely avoiding the causes of IAQ is almost impossible. Some — for example cleaning materials — can be removed relatively easily. But in cases where the fabric of the building or the geology of the site itself are concerned, that may be unrealistic, and building management strategies need to concentrate on reducing their effects. For example, a construction material might emit pollutants that degrade IAQ, but if the building is adequately ventilated they can be kept to acceptably low levels.

In search of a solution

There are three main approaches to addressing IAQ issues, which can all be used in combination.

First, you can clean the air,using commercial air purifiers to remove pollutants. This is something of a brute-force approach (it does not solve the problem of undesirable matter getting into the air in the first place) but it can be effective on a small scale, for example where one area of the building has especially high levels of pollutants from a local source.

Implementing it throughout a large facility is, however, unlikely to be practical.

More realistically, you can control the pollutants at their source.

As we’ve said, this is straightforward in some cases but impractical in others. However, a large number of apparently small initiatives can combine to have an appreciable impact.

One of the most obvious is to impose a non-smoking policy, either totally or by confining smoking to a smoking lounge. This should have negative pressure (see box “All About Air”) and be ventilated directly to the outside.Vehicle emissions can be controlled in a similar way, with negative pressure in the parking garage, and by discouraging the running of engines at the loading dock.

Emissions from maintenance products can be minimised by choosing low-emitting products, of course, but also by avoiding sprays and aerosols in general. They should be stored in sealed spaces, again ventilated to the outside.

Construction materials may be a harder issue to address if the facility has already been built, but improved ventilation will still help. When new construction is underway, recommendations include airing materials in an open area before use; keeping them dry; and ensuring that there is ventilation during work.

Similarly, issues with the earth or rock cannot simply be eliminated through changing behaviour as tobacco smoke can. But foundations can be sealed, and the ducts that bring air into the building can be kept away from the ground.

Finally, as so often with buildings, moisture is the enemy. Steps that can be taken here include insulating pipes as well as exterior walls and ceilings to avoid sweating and condensation; ventilating areas that produce steam, such as kitchens; and ensuring there is adequate drainage around the outside of the building. The aim is to keep the relative humidity (a measure of the amount of water in the air) to around 50% or less.

Temperature is a consideration too. Emissions, for example from building materials, are often greater at higher temperatures. So simply addressing heat and humidity within the building can pay dividends, while bearing in mind that a heating system is not the only influence on temperature — other heat sources such as electrical equipment, sunlight, and the outdoor temperature all have an effect too.

And then the third approach, complementing control of emissions, is ventilation. This means regularly replacing the air in the building by sending it outside and bringing in cleaner air. However, effectively ventilating a large space requires a lot more than opening a few windows.

Ventilation has several main components: outside air is introduced and indoor air exhausted by mechanical means, but there is also natural “air exchange” in both directions through doors, windows and other gaps in the building’s skin.

In an IAQ strategy, ventilation can have two quite different effects, though frequently they are used in combination. Exhaust ventilation means removing contaminated air, sending it outside. By contrast, dilution ventilation does not try to get rid of the pollutants entirely, but instead aims to dilute them by introducing clean air from the outside.

Exhaust ventilation is an option when the pollutant source is small and local (an exhaust hood on a kitchen stove is a familiar example); dilution ventilation is more practical when the sources are multiple and widespread.

Professional advice will likely be needed, because like most aspects of managing big buildings, ventilation is more complex than it sounds. And so, indeed, is air quality — air and its potential for causing problems might be invisible, but as building owners sometimes find out, the consequences are not.

All about air

Air is not a static thing. It moves around a building, and contaminants move with it as it flows. The flow is affected by many factors in the building’s design, including doors and windows, air intakes, fans, flues, ducts, stairwells, and elevator shafts.

Pressure is also key: like any other gas, air will naturally move from places where it is under high pressure to places where the pressure is lower. Temperature affects pressure, and so it too is a factor.

The upshot of this is that air pollutants can be found a long distance from the source of the pollution. For example, they can easily travel up several floors via a stairwell, or along a lengthy corridor if there is a pressure differential between one end and the next. A local pollutant can become a building-wide one.

Fortunately, this constant motion of air can be exploited to improve IAQ, too, and pressure differences are a powerful tool. Ventilation systems can create areas of lower or higher pressure in different rooms or areas of the building, by adjusting the relative rates at which air is brought into and expelled from that particular space.

Air, and the pollutants it carries, will never flow from an area of low (or “negative”) pressure into one of higher (or “positive”) pressure — the flow will always be in the other direction. So, if the main sources of pollution are kept under negative pressure while other areas of the building that people use are under positive pressure, the tendency will be for clean air to flow into the polluted space rather than vice-versa.

An obvious example of this is seen in smoking booths inside confined spaces, for example in airport departure lounges. Negative pressure within the booth means that air will flow into it, but not out into the rest of the lounge.

Ultimately, of course, the air is then expelled from the building altogether.

It’s the law

Regulation of IAQ — or of the factors affecting it — varies widely around the world. Probably the most common IAQ-related laws are those dealing with smoking in public places, and indeed the phrase “clean indoor air” in legislation is typically code for a smoking ban, as in the Nevada Clean Indoor Air Act.

The effect of smoking bans on casinos has been much discussed. Measures such as Macau’s are often seen as harmful to the industry, and casinos are sometimes among the few public premises exempt from such bans.

However, some countries go further in mandating clean indoor air, typically as a form of worker protection. In the United States, for example, the Occupational Health and Safety Act requires employers to provide a safe workplace, and the agency responsible for its enforcement — OSHA — has produced guidelines on IAQ.

While standards such as these address the actual air quality within a premises, building codes can also be drawn up to ensure that structures are likely to ensure good air quality.

In the US there is a patchwork of local codes but in some countries, for example the UK, they are more standardised. Britain’s Building Regulations provide detailed guidance on airtightness, ventilation, and radon, although they have been criticised as being more concerned with energy efficiency than air quality.