Hi alpharalpha,
You may have seen this already, but just in case:
Talalay Global’s blended Talalay comes in target ILD’s of 14, 19, 24, 28, 32, 36, 40, & 44. You can see the approximate density of each of these in post #2 here.
Radium blended Talalay comes in target ILD’s (rounded to the closest whole number) of 11, 15, 19, 22, 25, 29, 34, & 40.
Talalay Global uses a filler in their latex formula while Radium doesn’t.
Talalay Global 100% natural Talalay comes in N1 (14 - 19), N2 (20 - 24), N3 (25 - 29), N4 (30 - 34), & N5 (35 - 42) with nominal midpoints of about 17, 22, 27, 32, 38.
Radium 100% natural has ILD targets (rounded to the closest whole number) of 9, 13, 18, 23, 28, 33, 39, and 44
You can see a chart for Radium’sILDrangehere.
Most of the manufacturers that I’ve talked that work extensively with both say that they have a “comparable feel” although of course this is subjective. The difference between them would be relatively small and would probably reflect the different ILD’s, amount of filler, and any other differences in compounding formulas and pin core patterns they have. Radium has commented that they are unsure of the slight difference, and they think that perhaps is varies with how TG does their ILD testing. And remember that ILD is one of the factors determining overall foam plushness. Regardless, the differences would be small.
As for your latex “sensitivity” (imagined or real), there are different types of latex “allergies” that can be aggravated by frequent contact with the allergen (which usually aren’t the latex proteins themselves) but it would be no more likely to have an allergy to the latex proteins themselves than to many other materials that are used in mattresses and there is also no contact with the latex in a mattress because it has a cover.
While it is a complex subject, the essence of it is that there are basically 3 types of latex allergy or sensitivities (although two of them aren’t really an allergy to latex).
The first of these is irritant contact dermatitis which usually comes from an actual irritation to the skin such as from repeated donning of latex gloves or exposure to the powder on them often in combination with skin sweating or frequent hand washing. This is a result of physical skin irritation and wouldn’t apply to latex foam.
The second and most common of the “latex allergies” contact dermatitis allergies (type IV latex allergy) which is most likely a reaction to the chemicals additives or substances that are added to the latex in the manufacturing process and not the latex itself. This is more prevalent for those who have handled latex in various occupations over a period of time (such as health care workers using latex gloves). This is the less severe of the types of “latex allergies” and while it is not “common” it is also not so rare … particularly among certain occupations. Because latex foam has had most of the surface proteins and any remaining unreacted materials washed away during manufacturing (unlike other types of non foamed latex like gloves, condoms, balloons etc.), this is far less common with latex foam. This type of “latex allergy” is a contact allergy (or sensitivity) and the fact that most of the surface proteins and additives are washed away and that the latex is covered makes this type of allergy much less of an issue with latex mattresses. There is more detailed information and links in this thread and latex foam is not mentioned in any of the literature I’ve seen or linked as a possible source of this type of allergy.
The last type of latex allergy is type 1 which is much more rare but much more serious. This type of allergy can cause an anaphylactic reaction with breathing difficulties and swelling and like a bee sting in a small portion of the population can be life threatening. These people are almost always very aware of their allergy and have to go to great extremes to avoid natural latex which is very difficult because it is so widely used in our society. They for example have to check in restaurants where they eat that the workers aren’t wearing gloves with latex or they could have a severe reaction. This would be connected to the proteins found in natural latex which would be missing in synthetic latex.
You could be having a slight issue with the Type IV sensitivity, or it could be small reaction to some of the other materials present in the latex, or as latex is quite “sticky” it could simply be an issue of the high coefficient of friction of the foam causing a bit of redness. But as your finished mattress will be covered I personally wouldn’t have much of a concern.
Phoenix