“Sick Building Syndrome” is a term that has been around for a few decades to explain how and why people are affected by their buildings. As a building biologist, I am frequently assessing the health of buildings (whether they are sick or not) and how they may impact upon the health of the occupants – be that at home or at work.
Guest author Jennifer Bennett discusses sick building syndrome in relation to the workplace.
Sick Building Syndrome: Is Your Workplace Healthy?
Does it sometimes seem like everyone in your office is coming down with something?
Are you and your colleagues constantly coughing and sniffling, or complaining of headaches, dizziness and nausea?
Or perhaps you’re just really tired all the time?
And yet, when 5 o’clock rolls around and you’re on your way home, you start to feel a lot better.
You might be thinking that you just hate being at work!
Could it be more..?
However, there may be something other than burnout or a bad bout of the flu to blame.
If you’re experiencing odd symptoms that disappear when you go home, your building may well have a case of Sick Building Syndrome.
This is a somewhat mysterious condition that causes general feelings of ill health in occupants of a building, including headaches, aches and pains, skin irritation, fatigue and shortness of breath.
The precise causes of Sick Building Syndrome haven’t been identified, but the general consensus is that it’s a symptom of environmental problems within a building.
People first started reporting Sick Building Syndrome in the 1970s, when economic pressures and oil embargoes forced architects and engineers to design more airtight office buildings to cut energy costs.
As a direct result, indoor air quality drastically worsened, as polluted air became trapped in buildings rather than being recirculated outside.
Chemical pollutants such as VOCs and biological contaminants such as mould then gradually rose in concentration, resulting in the health problems in employees that we now call Sick Building Syndrome.
Poorly designed ventilation systems also resulted in uncomfortable temperatures and high humidity levels, which can further encourage mould growth.
What is the Impact?
A poor working environment doesn’t just have health implications – it can also have a profound economic impact on businesses.
Sick Building Syndrome drastically reduces productivity, with poor indoor air quality estimated to cost employers around $15 billion a year in worker inefficiency and sick leave.
It’s also been noticed that Sick Building Syndrome is most common in open plan offices, and it’s unlikely to be a coincidence that employees in open plan offices also take on average 62% more sick days than those in cellular offices.
It’s clear that something needs to be done.
This infographic…
Paint Inspection have designed this infographic to tell you everything you need to know about this important topic.
Covering everything from the symptoms and causes, to the costs to businesses and some actionable solutions, we’re sure you’ll leave this blog feeling more equipped to deal with your unhealthy office building!
About the Author
Jennifer Bennett is the Content Writer at Paint Inspection, a UK-based coating inspection and surveying company.
Humidity is not just a present in our rainforests, it is also present in our homes
Humidity is basically moisture levels in the air.
Relative humidity (RH) is what we commonly talk about, and the ideal range is between 45-55% RH.
Why? Because at this level, it is not moist enough to for most mould, bacteria and other microorganisms to grow. Thus, this is our levels of “no concern” in our Building Biology Standards.
This image depicts different activity levels at different levels of RH (Arundel, et al).
The best way to know what the levels are in your home or workplace is to use a basic hygrometer, such as this one.
RH levels affect our comfort levels as well as our experience of temperatures
When RH levels are high, temperatures feel a lot more oppressive… Think “tropics” and “wet seasons.”
When RH levels are very low, we feel dry – our eyes, throat and mouth can become irritated as a result. Too, we may experience more static electricity.
Why is Humidity an Issue?
Humidity is an issue because when a material is cold enough, this moisture will condense out of the air and can result in the proliferation of mould. Read more about condensation here.
In a recent trip to far north Queensland, I witnessed first hand what regular high levels of RH were like. The temperatures remained stable in the high 20s (celcius) and the RH levels were around 86% night and day. The buildings I saw had the air conditioning running full pelt, and as a result, there was water streaming down all the windows.
On further investigation, it was apparent that the building materials had varying temperatures, and some were cold enough to be below dew point. The result? In technical terms: mould in the interstitial spaces of the building… hidden mould – aka “invisible mould.”
Discover more…
In the video below as I share with you how to manage humidity in our homes.
Understand the difference between desiccant dehumidifiers and refrigerant dehumidifiers and which one is best for you.
Many of the homes I assess have essential oil diffusers.
Whilst I love that more people are using essential oils, I have concerns about the essential oil diffusers that harbour mould… and then potentially spread it throughout your home.
So, let me share with you ways to avoid mould – and fragrant oils!
Some key points about essential oil diffusers that require water:
they add moisture to your indoor air
the water inside them is infrequently changed
the tubes within them are impossible to dry out – and this is where I see the most mould – and they are equally impossible to clean!
Options:
use an electric oil diffuser – such as this one that requires no water at all
put essential oils on a cotton ball or tissue
grow fresh herbs and enjoy their aroma
Why we Don’t Want to Add Moisture to the Indoor Air
Mould spores are everywhere. They are an important part of our world. We just don’t want them growing in our homes.
Mould requires food and moisture to flourish. Usually the spores are sitting on food. So the thing that we CAN control is moisture.
When there is enough moisture (high humidity levels or a material is wet for 48+ hours) mould can proliferate. This sets off a chain of events, which for those who are sensitive or sensitised can be extremely problematic. Mould can be detrimental to our health as well as to the structure of the building.
Taking steps to reduce moisture levels is ideal – and avoiding adding it is even better!
Let’s first explore humidity – to set the scene and give context to the rest of this post.
What is Humidity?
Humidity is the amount of water vapour in the air. It is important to know and understand this, particularly if you have any water damage or you live in a humid environment.
Humidity is commonly measured and discussed in two ways.
Firstly, there is relative humidity – this is the one we hear about a lot. When you think of being somewhere tropical, where you feel clammy despite having just showered, these areas will have a high level of relative humidity. The level is given as a percentage, for example 62%.
Relative humidity is the measure of how much water vapour is in the air and varies according to the temperature, in that it is relative to the temperature. The warmer the air, the more water vapour can be held and thus the relative humidity level will be higher.
Specific humidity is a different measurement and does not vary with temperature. It is expressed as gpk (grams per kilogram) or gpp (grains per pound).
Ideal Levels of Humidity
There are no ideal levels for specific humidity. As a building biologist, the different readings in different rooms can show me where to look further for water damage, and this requires quite specialised equipment.
Relative humidity is the one that is easiest to measure and changes can be quite noticeable in the way it feels. This is the one more closely related to comfort. Relative humidity is easily measured using an inexpensive hygrometer, such as this one.
Most people generally feel comfortable when the temperature is between 18-24oC and the relative humidity is between 35-75%, beyond this people generally feel uncomfortable.
When relative humidity levels are high, the air is uncomfortably moist – you may feel hot and clammy, sticky or just damp.
When relative humidity levels are low, you may feel quite dry – dry eyes, dry throat, dry skin, “parched”; you may even experience more static electricity.
The optimum level for relative humidity is between 40-60%.
Bacteria, viruses, fungi and house dust mites all are less active; and these biological contaminants can be highly problematic for health, and form part of the microbial stew.
Occupant Activity and Humidity
Humidity can result in water damage.
In our homes, there are four main ways for water damage to occur. The first is a disaster of some sort, eg flooding. The second is damage to the building, eg a burst pipe, tiles coming off the roof, a leak. The third is poor building design or poor workmanship, such as not having an exterior vent on an extractor fan, having bedrooms with no opening windows, running the downpipes to the underneath of the house… And the fourth (which can often be overlooked) is occupant activity.
Occupant activity can cause a lot of water damage. Some examples are:
not using the extractor fan when bathing
using a clothes dryer
spilling liquids and not cleaning them up quickly
Examples of Moisture Created from Occupant Activity
The following is from Elkink and Pringle’s 2012 book Building Basics: Internal Moisture – and these levels, I am sure, will amaze you!
Activity
Creates
Showering and bathing
Varying levels of moisture depending on temperature of shower, length of time, ventilation.
People in a room
Awake we exhale 200ml of water vapour per hour. Asleep we exhale 20ml per hour. This is roughly 3L of moisture per day.
Unflued gas heaters
0.5-1L of water per hour.
Cooking
Varies depending on method (e.g. boiling and steaming), if the heat source is gas; and includes kettles, microwaves, dishwashers and washing dishes.
Clothes washing and drying
Up to 5L per load can be released if clothes are dried inside on a rack.
All produce enough heat and water vapour to require additional mechanical ventilation systems.
Humidifiers
Increase the humidity in a room and can result in condensation.
Accidental floods
Overflowing baths, sinks and laundry tubs can all create problems if not dried within 24-48 hours.
Roof space ventilation
This is important particularly if extractor fans are flued into the roof cavity, and not vented externally. Changes in pressure can cause moisture and other contaminants to enter the building.
Steam cleaning
A potential problem is created if the materials are not completely dry within 24-48 hours.
Leaking pipes and appliances
A very large problem, which will vary depending on what, where, how much, and how long before it is rectified.
A normal subfloor
Evaporation from a 93m2 subfloor is 45L of moisture per day, and up to 180L per day if there is standing water on the subfloor soil.
Ventilation
As you can see, there are a lot of ways that we can fill our homes with moisture – inadvertently, which is one reason why ventilation is important. My ideal would be for every home to exchange all of the air every few hours, and yet reality brings us back to at least once a day.
My favourite thing to do is to open windows and doors in the morning until I feel the temperature change, and I know that all of the air in my home has been exchanged.
I’ll come back to this a little later, but it is important to note that moisture moves to where levels are lowest… So, if there is less humidity outside, then opening your windows can allow the moisture to dissipate out of your home. If the relative humidity is higher outside, then it could be better to open your windows and doors when this has changed over.
How to Use a Dehumidifier
A dehumidifier takes the water vapour out of the air and it can be used to bring relative humidity levels back into the optimum zone – between 40-60%.
I like people to have them, particularly when the cause of the moisture is occupant activity or a lack of ventilation (such as a rented property with no extractor fan in the bathroom).
Here is a general step-by-step guide for how to use a dehumidifier for the initial deep-drying. Please note that every house is different, so this is merely a guide.
If you have pets, like birds, etc, please take them out of the room first.
Close the windows and doors of the chosen room.
Open cupboards and drawers in this room.
Set your dehumidifier to 30% relative humidity.
If temperature of the room is low, turn on the heater (or the heater on the dehumidifier) for optimum drying.
Run the dehumidifier for 24-hours a day for 1-3 days.
A good dehumidifier will automatically turn itself off when its water tank reaches capacity – so you should be able to run it while you are at work (they are a bit noisy, so this is preferable to running them overnight).
After this initial drying phase, you can use it periodically to dry the room.
NOTE: If there is water damage and/or mould, I recommend that a) the source of the water is addressed and b) if anything is wet for more than 48 hours that the resultant mould be addressed first.
When Else a Dehumidifier is Useful
A dehumidifier, as mentioned is great for moisture caused by occupant activity.
My #1 use for a dehumidifier, in an ongoing way, is to use it in the bathroom or ensuite when bathing. Despite using it regularly, it always astonishes me the amount of water vapour that a shower can produce.
It can also be used when you are exchanging the air in your home, and the outside relative humidity is higher than the indoor relative humidity.
If you get a good one, it will also have a heater on it. This is beneficial as you now have a clothes dryer – that doesn’t add moisture to the air! Simple hang your clothes on a rack and run the dehumidifier nearby (wishing I had one when I lived in the Blue Mountains, where it took weeks to dry my laundry!)
Which One Do I Recommend?
I have sought out one that I like (I stock it for this reason) – I personally own this model and use it every day.
This is the New Wide Tech All Seasons 35L Dehumidifier.
Basically, bigger is better, it does the job more efficiently and has a greater water capacity.
What else to look for?
variable humidity settings
the water tank will automatically signal when it is full and the dehumidifier will stop working
a ceramic heater to help dry more quickly and allow it to work well in cooler climates
option for continuous drainage
When a Dehumidifier is Not Enough
As much as I am a fan of the dehumidifier (pun not intended) – there are times when one is not enough. My biggest concern with recommending them is that someone may have water damage to their property with resultant mould.
Mould spores are everywhere and just need water as the spark of life… anything that is wet for longer than 48-hours can be a problem – even if it is dry now.
Read more about mould here and mould, water damage and health here.
A dehumidifier is fabulous for occupant activity, but not ideal (without professional assessment) when there is something more going on, eg structural damage…
So, these factors would give you an indication that you should look beyond just drying out the room with a dehumidifier:
You (or someone in your household) is unwell, and generally, your health improves when away from the home
You have mould
Your home (or parts of it) smell musty, mouldy, damp, dank or earthy
Your clothes are always damp
There is a history of water damage in your home
You have a leak
There is water under your house
Obviously, the above list does not cover everything. Mould is a serious problem, and it is a moisture issue. Addressing the source is paramount to resolving the issue.
(This post is intended to be informative, and not an infomercial. Given the gravity of biotoxin/mould-related illnesses, please understand that I do need to point out the limitations, and how you can action the situation.)
References
Aderholdt, J (3 August 2011) The Insulation Lab (Online) Available at http://www.ntcinsulation.com/the-insulation-lab/moisture-_psychrometrics_and_relative_humidity_-_their_effect_on_structure_and_air_quality (accessed 28 November, 2016)
Elkink, A and Pringle, T (2012) Building Basics: Internal Moisture Building Research Association of New Zealand, Porirua, New Zealand
ProAir (2011) Indoor Air Quality (Online) Available at http://www.proair.ie/the-technology/indoor-air-quality/3/ (accessed 28 November 2016)
