ON MATTRESSES
Some friends of mine have just spent the better part of $2000 on a mattress and a box. They didn't mind the money so much as they resented the confusion and uncertainty they were subjected to by various sales people at the three or four stores they spent the last couple of days visiting.
The problem, it seems, is that there is a good deal of jargon used - which is non-standard and confusing. In fact, I suspect that it is a lot of deliberate nonsense.
Take, for example the term support. What, precisely does this mean? Is it it good to have support? If this be so, is more support better? What about a hardwood floor... does it have lots of support? If it does, then surely there has got to be a way of measuring support. "I would like a bed with support index 7 please".
Is support the same thing as firm? What about hard?
Then there is all that stuff about coil count and wire thickness and how the coils are tied together. What we need is a measure of springiness.
I went through all this crap myself a couple of years ago. I gave up. I now sleep on three layers of foam. 3 inches of firm foam on the bottom, 3 inches of softer on top of that and an eggcrate layer on top. Never been more comfortable.
Now, I appreciate that different folks have different preferences and indeed, some people will sleep best on some sort of clunky spring and box arrangement. But the problem is that there are no useful descriptors that can be used to compare one item with another.
So here is Brochmann's proposal for establishing a (there are probably several possible) measure for comparing one mattress with another.
The apparatus consists of a disk of some standard diameter, lets say 10 cm, which is pushed into a mattress by applying various weights.
The distance that the disk is forced into the mattress by each applied force is shown on a scale.
In this way one could produce graphs that would be characteristic of different mattress types.
For example, a mattress that obeyed Hooke's Law [deflection is directly proportional to applied force] in an ideal manner, would look like this:
mattress2.gif
One might hypothesize that this is what one might expect from a set of spring coils that were isolated from each other so as to be able to move totally independently.
Suppose now we made a mattress consisting of several layers of foam; with the top layer being very soft - such as an eggcrate and succeeding layers downwards being increasingly firm.
This arrangement, one would expect, might produce a graph something like this:
In any event - graphs of this type would allow one to assign meaning to commonly used terminology such as soft, firm, support, etc.One more time. If you are aware of accepted standards or descriptors in the mattress business I'd like to hear about it.
This morning, while cruising the net, I came across a number of sites that represent manufacturers of "pressure reducing support surfaces" for the wounded and bed ridden. The idea is that these people are prone to bed sores which result from high pressure areas particularly in the buttocks and shoulder blades.
Various arrangements of foams and gel layers enclose air filled cells. In some cases the air filled cells are deflated and inflated on a continuing basis by an electric pump so as to 'massage' unmoving bodies. Never having tried any of these; I'd imagine they might be the ultimate in comfort. One thing's for sure... I've never seen any of these arrangements in any sleep store.
In response to an enquiery I have received this e-mail:
December 21, 1999
To Harold Brochmann,
Thank you for your e-mail to us. Sorry for the delay in getting back to
you. Fortunately, the standards you were looking for in your e-mail exist
in the foam mattress industry. Unfortunately, we do not know if they exist
in the spring mattress industry. We deal exclusively in 100% foam
mattresses.From our web site ( www.foamshop.com ) you will find introductory
information about how we classify our mattresses. There are usually 4
numbers; the first two being the density, or measure of quality and the
second two numbers refer to the ILD or firmness.Density (the first two numbers): This is a measure of how much foam is in a
mattress per cubic foot (cuft). Any mattress that is measured at 2 pounds
per cubic foot and over is considered a high density mattress and is
suitable for every night use. We have three quality ranges of high density
foam which all provide great comfort and resilience:
our Royal 2.0lb/cuft - life span 10 years;
our Elite 2.5lb/cuft - life span 15 years;
our Ultra 3.0lb/cuft - life span 20 years.Foam that is less than the 2lb/cuft range is considered a low density foam
and is only acceptable for occasional use. It would lose its resilience
quickly if slept on every night.ILD (the second two numbers) or Firmness: This figure shows the firmness of
a foam mattress. Density does not equal firmness. You can have a 3lb
density foam mattress that is soft or hard and you can have a 1lb density
foam mattress that is soft or hard. ILD (Initial Load Deflection) is the
measure of softness and hardness. More specifically, the industry standard
for measuring ILD is:A foam block, 15 inches square and 4 inches high is pressed down 1 inch by
an 8 inch disc. The pressure reading for pressing the foam down 1 inch is
the ILD. The higher the ILD, the firmer the mattress.For all these measurements there are acceptable tolerances.
For example, if you want a medium-firm Royal (2lb/cuft) mattress, which has
a life span of 10 years, the industry code for it would be 2031. '20'
refers to a 2.0 lb/cuft foam and '31' refers to the ILD (Medium firmness).Example 2: if you want a firm Elite (2.5lb/cuft) mattress, which has a life
span of 15 years, the industry code for it would be 2540. '25' refers to a
2.5lb/cuft foam and '40' refers to the ILD (firm firmness)Please let us know if you have any further questions.
Sincerely,
Foort.*** The Foam Shop, Your Comfort Stop ***
Find us on the web at www.foamshop.com
or call us at 1(800) 567-90506 greater Vancouver locations to serve you better!
Find us in the Yellow pages under Foam or Mattresses
I include it here because it's the only really useful response I got from many enquieries.
