MHRV or PIV as an air pollution countermeasure?

[rark]

Good evening,

 

Can anyone suggest what a ventilation system would look like if the main objective was to protect the occupants of a bungalow from high levels of outdoor air pollution?

 

We live in a 1960's steel frame bungalow - not very airtight or particularly well insulated (not the worst, but not that good either). Our neighbourhood is heavy with wood burner smoke in the evenings with regular episodes of bonfire smoke during the daytime. It really is bad!  Anyway, currently we are unable to keep this pollution out of our home and our children are becoming asthmatic as a result. 

 

Obviously I need to come up with some sort of a solution. I am aware of MHRV systems which specify a F7 air filter for some protection against sub micron particles. Presumably it would be possible to upgrade to a more industrial filter with activated carbon. However I am unsure of the implications of installing in a fairly leaky property.

 

PIV seems like it would be much simpler to implement but the units I have seen advertised only seem to have  basic low grade filtration. Also don't PIV systems make for a cold house in winter?

 

Hoping to benefit from the forum's collective expertise in this area

 

Thanks 

 

Mark

[SteamyTea]

Question what you do inside the house first.

Animal detritus (including humans), lint and microfibres from clothing/furniture, cooking etc will all have a greater impact than what is happening outside.

 

And mould spores.

Edited October 22, 2022 by SteamyTea

[gc100]

Move?

Probably a MVHR would be better as you won’t have to deal with heat lose winter months and it will be distributing fresh air around your house, but you’ll need more piping and therefore more up front cost.

 

If your neighbour is really making your children asthmatic I’d be having a good conversation with them and failing any resolution I’d see what my legal options where given their actions are impacting your childrens health as I’m sure you will have some rights around this.

Edited to add : https://www.gov.uk/guidance/nuisance-smoke-how-councils-deal-with-complaints

 

That would be my first route after a discussion. Film and document a months worth before submitting all evidence including a doctors note if possible. 

 

Edited October 22, 2022 by gc100

[rark]

Thanks for the replies.

 

Moving is not on the cards ATM and I suspect you would be amazed how weak the law is in this area. For example Environmental Health would only get involved if I could prove the smoke was from a particular individual and was happening on a regular basis. They have confirmed to me that bonfires are basically allowed - no matter how obnoxious - as long as they only occur on an 'occasional' basis! Yep, treating the atmosphere as an open sewer in 21st century UK is apparently ok - the right to burn garden rubbish must be upheld :-(

 

The situation with woodburners isn't any better. Even if I present evidence of high PM2.5 levels inside my property when the air is smoky outside; if the woodburner in question complies with building regs then the law offers zero protection - sad but true. 

 

I did used to confront people over bonfire smoke but they just seem to dig their heels in and deny the smoke is in any way harmful and I can't see people who have paid the have a woodburner retrofitted agreeing not to use it especially with the antics of Mr Putin.

 

 

So unfortunately it comes back to trying to filter the incoming air.  I found another thread on here where someone added an activated carbon filter to an existing MHVR setup to protect his house from bonfire smoke so it seems there is hope!

[JohnMo]

You can do similar to PIV also.

Edited October 22, 2022 by JohnMo
Missed word

[rark]

Yes i'm leaning toward this option as it would be quick to implement  -  buy a PIV unit and join it to a filter big enough so it doesn't cause a pressure drop and see how cold it makes the house and whether it keeps the pollution out 

 

I wonder why the PIV manufactures don't sell them with high grade filtration seems they are missing a potential market...

Edited October 22, 2022 by rark

[rark]

On the subject of filters...anyone know if the activated carbon should be before or after the HEPA filter?

[JohnMo]

Not sure what flow rate you need.

 

But you could use something like this for the filter, has pre filter, H13 and carbon

 

https://uk.rs-online.com/web/p/soldering-fume-extractor-accessories/0391359

[JohnMo]

Also found this

https://www.juiceelectricalsupplies.co.uk/product/dri-eco-nox-hc-nuaire-drimaster-eco-nox-ventilation-system-piv-carbon-filters/?gclid=Cj0KCQjwqc6aBhC4ARIsAN06NmO_Ys_lzHNklnO_vJ_a1Eh14_dE_0lMrfyB9mqu8KTYSGntW5-p-IwaAhTSEALw_wcB

[Ferdinand]

On 21/10/2022 at 20:38, rark said:

PIV seems like it would be much simpler to implement but the units I have seen advertised only seem to have  basic low grade filtration. Also don't PIV systems make for a cold house in winter?

 

PIVs usually have an minimum inlet temperature at which they cut out to prevent making the house much colder. Likely to be something like 5C.

 

Alternatively, some have a heating element in the airflow that can be switched on. I presume that may also be triggerable on the temperature, but I have not checked any models.

 

F

[Carrerahill]

On 21/10/2022 at 20:38, rark said:

Good evening,

 

Can anyone suggest what a ventilation system would look like if the main objective was to protect the occupants of a bungalow from high levels of outdoor air pollution?

 

We live in a 1960's steel frame bungalow - not very airtight or particularly well insulated (not the worst, but not that good either). Our neighbourhood is heavy with wood burner smoke in the evenings with regular episodes of bonfire smoke during the daytime. It really is bad!  Anyway, currently we are unable to keep this pollution out of our home and our children are becoming asthmatic as a result. 

 

Obviously I need to come up with some sort of a solution. I am aware of MHRV systems which specify a F7 air filter for some protection against sub micron particles. Presumably it would be possible to upgrade to a more industrial filter with activated carbon. However I am unsure of the implications of installing in a fairly leaky property.

 

PIV seems like it would be much simpler to implement but the units I have seen advertised only seem to have  basic low grade filtration. Also don't PIV systems make for a cold house in winter?

 

Hoping to benefit from the forum's collective expertise in this area

 

Thanks 

 

Mark

An air handling unit of some sort, with relevant filters on the intake. Common on new flatted developments, student accommodation, hotels, etc. etc. particularly in London.

 

You don't need to buy a "system" you could buy a filter chamber on say 125mm duct inlet/outlets. Then couple with an inline fan and duct it out to the rooms, this would, at the most simple level bring in filtered air. The issue here would be that you would pressurise the space and drive out warm air, so you probably want to incorporate heat recovery on an extract system. 

 

If the WB smoke is heavy I would be asking why and looking to see if this could be addressed too - properly seasoned wood and properly run WB's should not emit heavy smoke - are you rural?

 

Edited October 24, 2022 by Carrerahill

[SteamyTea]

1 hour ago, Carrerahill said:

If the WB smoke is heavy I would be asking why and looking to see if this could be addressed too - properly seasoned wood and properly run WB's should not emit heavy smoke - are you rural?

Not going to make much difference to the PM10 and PM2.5s.

Smoke is unburnt fuel usually, it is the combustion by products that give the health problems.

 

[Carrerahill]

On 21/10/2022 at 20:38, rark said:

Obviously I need to come up with some sort of a solution. I am aware of MHRV systems which specify a F7 air filter for some protection against sub micron particles. Presumably it would be possible to upgrade to a more industrial filter with activated carbon. However I am unsure of the implications of installing in a fairly leaky property.

 

Grade F7-F9 filters. We commonly specify filter packs capable of removing down to PM1.0 (arrestance is not as high as for larger particulate but it works).

[rark]

Thanks for the replies everyone.

 

I invested in a device which measures PM1, 2.5 and 10. Interestingly the last week's readings have been generally low (less than 5micrograms/cubic meter. However the mild weather means the woodburning has not fully started yet. We haven't had any nights yet when the air has been really stinking of woodsmoke. I will report back when this happens.

 

I think a way forward would be to obtain some suitable filters and install some sort of fan in the loft to be used on demand when the pollution is bad.  I am slightly worried about mould growth within the fan unit when not being used. I suppose the unit can be kept accessible for regular inspections. Anyone know if mould is considered a real world problem when  MHRV/PIV blowers are situated in a cold loft space?

 

Regarding the F7-F9 filters - posters on other threads report bonfire/woodsmoke smells not being kept out by these filters. Some of the smoke pollutants must stay in the gaseous phase and need activated carbon to remove them

[Seren161]

Don’t know if this is of any use to you but simple standalone air purifiers can be very effective for improving air quality within properties. They are plug in and there is the relatively low background sound but usually configured as 3 filters and the option of carbon ( activated charcoal usually) filters as add ons. There is a wide price range and you probably change filters every 9 months….I have quite a few of these in my work premises( a leaky edwardian terrace) and during the pandemic which we worked through…no covid or cold transmission occurred in our workplace..so pretty effective if you get the right sizes..Have a team member who catches every respiratory virus available and in the 7 years or so we’ve had these purifiers..they have noticed an amazing reduction in colds etc. I use a company called Breathing Space.. lots of info on the website..I personally use the larger BlueAir health protect ones