In an article in tonights Marlborough Express, there were a few interesting observations.
Firstly, there's been a resource consent granted to use a Defender fan on a block out Seddon way. I'm going to assume that this means that the new Defender has been tested and has passed the requirements under the proposed plan changes. Good news for them.
I'm still a bit in the dark of course. I mean they appear to have a new fan doing the rounds, but it's a picture of the old one that appears on their web site along with their historical shocking propaganda 'testing' data from the University of Canterbury. It never fails to surprise me that people can spend a bazillion dollars on R&D and still expect to put up a public 'face' on a web site with incorrect data and in one case even a missing image.
Secondly, there's some information on the long running battle up the Waihopai with Waihopai Holdings or Mount Riley as the parent company's called. To be brutal, it would appear as if the person writing the article has got things a bit topsy turvy, unless of course there's been some RADICAL changes in the way that bun fight has developed. Interesting to see that they appear to have been granted a right to use one fan and are applying for another?? I thought this was all heading to court to sort out, so perhaps there's been some movement.
This all smells a bit fishy and half-baked fish at that.
Tuesday, 7 September 2010
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6 comments:
It also appears the vaunted new non breaking Defender still has a 5 dBA special audable noise penalty on it, taking it over the 55dBA level under the new District Plan.
To comply, just like the Orchard Rite and Amarillo blades, the speed has to be wound back to comply.
This also begs the question why are the council hell bent on putting Defender blades on the block next to Sarah Stringer when the special noise character still exists. Some one may have a gilded finger.
Interesting opinion!
Obviously one that I have presumed for some time. However, only independent testing can cover that base.
Hi Jack
from my digging of information i have found that actually all frost fans in the market today and yes that includes the Frost Boss 4 bladed machine are subject to special audible penalty so i guess they have all been turned to a certain rev limit to allow them just inside the law.So it must come back to who covers the most area therefore is further away from the next door houses when thinking of which is the quietest machine .Interesting huh?
Anonymous.
I almost agree with you on the special audible penalty issue. To my knowledge, all older models of fans have been independently assessed as exhibiting either tonal or impulsive qualities that attract a 5dB penalty. This includes the old-school 4 bladed Frost Boss.
However, I haven't seen any independent testing released for the Defender or the C-49. The University of Canterbury (the same people who developed the fan) released a report that claimed the Defender didn't attract the penalty, but it looks as if they didn't include impulsiveness (amongst other issues). So their testing was neither independent or complete in my opinion. Likewise the word on the street is that there is still a significant 'Chop-Chop' sound. The C-49 looks very pretty, but There hasn't been any independent (or otherwise) testing released. So at this stage Special Audible Characteristics is still a factor for all fans as far as I am aware.
I also think it would be a dangerous assumption to presume that fans are being tuned to comply with noise regulations. From Malcolm's testing last year (40 odd fans) only the 4 Bladed Frost Boss and a handful next to people who are at the end of their tether seem to be complying.
Likewise, making a fan cover a larger area typically means increasing the flow of the fan (apparently this relationship is linear), but this occurs while increasing the rpm of the fan and the resulting noise increases on a curve. Greater coverage = more noise I believe.
Hi Jack
sorry maybe I did not make myself very clear .I meant as of this season i would assume all fans being put in are tuned to suit current laws as the council will no doubt be checking each and every one going in ?
so the point i was making was say a fan is 50 db . If it protects a 400m circle (in theory) and another fan that also produces 50db protects a 300m circle then the noise emitted by the machine protecting the smaller area will be greater at the nearest residence and there will be more cumulative effect as more machines will be needed per hectare.correct?
Ahh.. I think I understand. In theory the net setback rule will also prevent a fan from getting too close acoustically (i.e. it doesn't matter that it is, more that it doesn't get too loud close to a residential area). So I think that problem is covered. However, you are correct in thinking that if there were a lot more machines protecting a smaller area, their cumulative noise will be greater. This could become a problem and it is an area that was deliberately not covered in the new rules on the basis that there wasn't enough data accumulated to make a ruling. They specifically stated that it should be addressed when / if the problem is properly understood. I.e, there might be a problem, but no-ones ever said "looks there's 72dBALeq at my doorstep". No science = no ruling. Strangely enough that actually makes sense. The onus is on affected people to prove there is a problem. However that doesn't ignore the fact that ignoring cumulative effects is ignorance :-)
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