Written by Lightspark staff with contributions from Sonny Pirrotta, National HVAC Manager, IAQ, Panasonic Canada and Robert Bean, ASHRAE Fellow and distinguished lecturer on energy efficiency.
The past few weeks in Alberta and around Canada have seen some of the most terrifying wildfires in provincial and national record. Scenes of towering infernos scorching forests and decimating entire landscapes have drawn the attention of news outlets around the world. Over 1,000 firefighters from across North America and elsewhere have joined in relief efforts, with dozens of fires growing across the province.
On top of the obvious wildfire risk, smoke hazards have seen Alberta’s air quality downgraded to among the worst in the entire world. In Red Deer, Edmonton, and elsewhere, the Air Quality Index has risen to ‘Very unhealthy’ levels – as high as 241 on May 22nd, on a scale where 10 is roughly the current average for cities in British Columbia. This has led to multiple air quality hazard warnings, and to repeated warnings for citizens in the affected areas to stay indoors.
Unfortunately, such warnings have seemingly become commonplace in the summer seasons. With extreme weather events becoming annual occurrences, home owners are increasingly seeking ways that they can protect their homes and families. While wildfires pose an obvious risk to those in their immediate vicinity, the spread of smoke is a very real, province-wide hazard. Here are three things you can do to help protect your home against smoke as we enter wildfire season.
1. Use a high-efficiency HVAC filter in homes with heating and cooling systems
This is an absolute must. If your home runs a centralized heating and cooling system, you should be regularly checking the quality and state of your system’s filter. Change your filters more regularly, particularly if you see a visible build-up of residue. In addition to helping cleanse the air in your home of smoke smell, HVAC filters with high MERV ratings can better remove the more harmful smoke particles from the air.
MERV – or Minimum Efficiency Reporting Value – ratings are a standardized system to help determine how effective your HVAC system is at filtering out harmful particles. The scale runs from 1-16, and the higher the MERV rating on your system, the more effective it is as filtering out particles.
When considering your HVAC system, look for systems with a MERV rating of 13 or above. Systems with a filtration rating above 13 are required for buildings that require excellent air filtration, like hospitals and laboratories. These systems are especially effective at filtering out smoke particles, and can help ensure that the air quality in your home is optimized. Make sure your home has additional filters, as they will need to be changed frequently during a smoke event. If you cannot find a system with a rating of 13 or above, you should consider a system with a MINIMUM rating of MERV-6. In the event of visible smoke, filters with MERV ratings above 6 will do a manageable job at filtering out the most harmful particulate matter. Still – the higher the rating, the better.
If you aren’t sure where to look for this information, or if you are interested in a new HVAC or filtration system for your home, Lightspark can help. We can connect you with trade professionals who can come to your home and guide you through ensuring that the air in your home is as clean and safe as possible.
2. Do NOT use portable air conditioners or evaporative coolers
The main threat to public health from wildfire smoke is considered to be particulate matter, with PM2.5 contributing approximately 90% of the total particulate mass (Vicente et al. 2013) and traveling great distances from the source of the fire. Carbon monoxide exposure from wildfire smoke does not pose a significant health hazard to the public, as it does not travel far from the original source (US EPA 2019). However, in the event of an improperly vented or malfunctioning combustion appliance, or if the source of the smoke is close,
“Fine particulate matter is a real threat to public health from wildfire, as these pollutants travel great distances from the fire and can cause respiratory issues,” says Sonny Pirrotta, National HVAC Manager, IAQ, Panasonic Canada. “Well-sealed buildings with high performance HVAC systems help you keep the nasty stuff out.”
There are still things anyone can do to boost indoor air quality during a smoke event. “Gas stove tops or exhaust fans should be limited to when outdoor smoke levels are low,” Pirrotta says. “A common mistake is to turn exhaust fans on when it’s smokey, but this can increase infiltration of outside air. Carbon monoxide is usually only a problem when the fire is close, but situations can arise when a combustion appliance is improperly vented or malfunctioning. It’s safer to use electric heating and cooling solutions — and even appliances such as induction cooktops — over fossil fuel combustion.”
Many homes without central air systems rely on single or dual-hose air conditioning systems to cool rooms down in the hot summer months. This is a convenient, generally low-cost alternative to the full-home overhaul that comes with central air installation. Condos and townhomes rely heavily on such systems, and they vary wildly in terms of energy consumption, they are understandably necessary parts of the modern home.
Unfortunately, they are also extremely inefficient at keeping out wildfire smoke. As most hose-based systems lack any sort of air filtration system, they do very little to keep out harmful wildfire smoke – and may actively be working to bring it into your home. As such, it is highly recommended that you avoid using your hose-based portable air conditioner as much as possible during instances of low air quality. While this may be difficult to do when it is particularly hot out, you should avoid such usage wherever possible.
Evaporative coolers are also not advised during times of high smoke circulation, as they act in a similar way to hose-based air conditioners. They do not filter out smoke particles, and can often worsen the air quality within a home.
3. Close your windows and check for leaks and gaps
One of the first things you should do during times of air quality warnings is to check your windows and doors. Firstly, leave them closed as often as possible. This goes without saying, and is the most effective way to keep smoke out of the home.
Secondly, check for leaks and gaps around the edges – particularly of your windows. Draft Proofing is a simple process, and can be an effective (and non-intrusive) way to ensure that you aren’t letting unwanted outside pollutants into your home.
If you are finding more significant cracks or gaps in your windows or doors, it may be time to replace them. Lightspark can help connect you with contractors in your area who can consult on or repair any deficiencies you find in your home.
If you’re looking for ways to donate to Wildfire Relief can do so through the Canadian Red Cross or by texting DONATE to 41010 to give $20 to support registered charities providing wildfire relief around the country.
4. Avoid appliances that generate heat on hot days, as this can create overheating for cooling systems
According to Robert Bean, ASHRAE Fellow and Distinguished Lecturer, “there is potential for overheating when shutting off cooling systems connected to the outdoors. As such, you should follow standard protocol, such as avoid using any heat generating devices during poor outdoor air conditions.”
This would include avoiding:
- Avoiding cooking and cleaning where the stove or dishwasher or washing machines are used and using dishwashers
- Avoid using electronics like TVs and computers which generate a lot of heat.
- Reducing where possible any solar loads on the building with shading such as exterior blinds
- Occupying the cooler areas of the home, such as basements
- Avoiding physical activity and hydrate to keep your metabolic rate down
- Using a combination of light clothing and fans to stay cool
- Consider recirculating air over a HEPA or air cleaner (with better than MERV 13 rating)
- If for whatever reason, smoke enters the home due to building physics and performance you can protect you and your family’s lungs by wearing an n95 respirator as necessary, and you might want to even consider keeping one on hand in the car, because your car can’t keep filter all the smoke on really smoky days