CA1261278A

CA1261278A - Earplugs

Info

Publication number: CA1261278A
Application number: CA000502486A
Authority: CA
Inventors: Robert N. Falco
Original assignee: Cabot Corp
Current assignee: Cabot Corp
Priority date: 1985-03-29
Filing date: 1986-02-21
Publication date: 1989-09-26
Also published as: GB2173110A; CH668904A5; JPH0759240B2; GB2173110B; ZA86897B; DD246479A5; NO860426L; FI87729C; ATA44386A; FI860748A; DK165899B; AT389636B; IT1212122B; SE8600689L; AU5387686A; SE463847B; DE3605597C2; FR2579456A1; AU590540B2; FR2579456B1

Abstract

ABSTRACT

An earplug composed of a resilient polymeric material and comprising an elongate stalk member having a nose end, and a flange array comprising at least three hollow, rearwardly extending flange elements of substan-tial circular cross sections and of serially increas-ing diameters integrally affixed to the stalk member at spaced intervals along at least a portion of the length thereof, the flange element of the smallest diameter being located at the nose end. Each flange element is of generally hemispherical shape, and comprises a thin skirt having a substantially uniform thickness of between about 0.008 inch (0.20 mm) and about 0.050 inch (1.27 mm). It is composed of a resilient polymeric material of construction having a Shore A Durometer hardness value of between about 10 and about 90. The diameter of each portion of the stalk member underlying each skirt is such as to define an annular free space between the interior surface of said skirt and said stalk member. This earplug is comfortable to wear properly and provides competent acoustic sealing of the ear canals.

Description

Title: EARPLUGS
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Field nf the InventiQn The present invention relates broadly to earplug~ and ~
more specifically directed to a resilient polymeric multiple flange earplu~ construction useful as a heariny protector.

:Ch In the United State~ one of,the better known earplugs of the general type contemplated by the present invention i~ that known as the "V-51 R", the construction details of which earplug are disclosed in a report entitled ~evelopmen~ of,an_~xtra Small and Extra Large Size for the V-51 ~ Ea~plug, D. T. Blackstock and 9.
Æ. Von Gierke, April 195~, Aero Medical Laboratory, Wright Air Development Center~ Air Research and Development Command, United States ~ir Force~ WADC Technical Report 56-142. This earplug was developed during the course of World War II in order to provide improved hearing protection to memb~r8 of the military who are ~ubjected to concussive sounds, ~uch aæ gunfire or explosions or to extremely noi~y work environment~, ~uch as at airports or aircraft maintenance facilitiesO ~he V-5,1~R earplug is composed of a resilient elastomer;c material, such as neoprene rubber, and comprises a single retroverted flange element extending from the nose end of a tubular rubber stalk member~ The flange element extends rearwardly f rom the nose of the tubular rubber stalk and is so spaced theref rom as to provide a free annular space therebet~een. In use, the earplug is forceably inserted into the ear canal, thereby at least partially collapsing the rearwardly extending ~lange element into the underlying free annulàr ~pace and conforming said , . j >-~

~lange element into an acoustic sealing relationship with the constraining wall~ of the ear canalO

In U.S. Patent No. 2,427,66,4r J. Y. Dunbar and J. S. Knight, ~eptember 23, 1947 and U.S. Patent No. 2~717,596, J. S. ~ight, September 13, 1955, there are disclosed earplugs similar to the V-51 R earplug described in the aforementioned Blackstock et al.
report. In Figures 2 and 3 of U. S. Patent No~ ~,427,664, there is additionally depicted an earplug comprising four disk-shaped flange elements of serially increa~ing diameters extending substantially transversely of the supporting stalk member. As is most clearly seen in Figure 3~ all ~our flanye elements of the construction are disclosed to be insertable into the ear canal and are biased somewhat rearwardly by the constraining walls thereof~

Unfortunately, earplugs of the type disclo~ed in the foregoing publications and in those varianks thereo~ known to the present applicant are of ten possessed of several disadvantages. Firstly, when properly worn a certain significant proportion of the wearar population often experiences discomfort in the use o~ such plugsO Generally this discomfort is perceived as a sense of excessive pressure being brought to bear on the walls of the ear canals, which pressure can be of such magnitude as to be painful. A common user response to such di scom~ort is to withdraw the offending earplug from the ear canal to the point where the perceived exce~sive pressure is relieved and, when this is done~ as often as not the acoustic seal between the plug and the eax canal is broken 9r weakened, thereby destro~ing or at least compromising the intended Aearing protection fl~nction ~f the earplug. This is a particularly pernicious deficien~y because, while the sub~ect .

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person involved may seem from outward appearances to be suitably hearing protected in fact, he or she may not be protected at all. Secondly, due to the well known anatomic variability of sizes and shapes of ear canals throughout the population, including the variabilit~ which often exi8t8 a~ between the ear canals of an individual user and the variations in 8iZ e of individual ear canals which occur naturally, it is generally required that flanged earplugs be produced in a number of size~
and that they be carefully fitted by trained pe~sonnel in order ~o to as~ure the attainment o~ competent hearing protect1on. For instance, the V-51 R plug mentioned above is presently produced in five different di~crete size~ whlch, according to the a~orementioned Blackstock et al~ report, provides the ability to properly fit 80-85% of the adult male user population : 15 therewith. Obviously, the requirement to produce multiple ~izes of an earplug adds greatly to the cost and complexity of manufacture thereof. In accordance with the pr~sent invention, however, there is provided a multiple flange earplug which can be produced in a single si~e and yet com~ortably fit and provide effective hearing protection for the great majority of the population.
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Objects of~h~ I~Yention It is a principal object of khe present invention to provide a new and novel multiple flange earplog.

: 25 It is another obj ect oiE the invention at once to provide a novel multiple ~lange earplug con~truction which is comfortable to wear properly and which provides competent acoustic sealing o~ the ear canals.

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It is still another object of the invention to provide a novel multiple flange earplug con~truction which may be produced in a single size and which earplug will properly and comfortably fit up to 98~ of the entire adult user population.

It is still another object of the invention to provide a novel multiple flange earplug construction wherein the flange elements may be readily manipul.ated to expose normally hidden portions of the earplug ~uch as for purposes of cleansing thereof.

Other objects and advanfages of the present invention will in part be obvious and will in part appear hereinafter.

In accordance with the invention there is provided a multiple flange earplug composed of a resilient soft polymeric material, said earplug comprising a stalk member carrying thereon an array of at least three hollow rearwardly directed and spaced apart flange elements of substantially circular cross ~ections, the first o~ which elements extends from the nose end of t~e s~alk member~
; 20 Each of the flange elements of ~he array comprises a skirt of relatively thin uniform thickness and is compo~ed of a soft resilient polymeric material having a Shore A
:~ Durometer hardness value of between about 10 and abou~ 90 The flange elements of the array increase serially in diamelter, ~tarting from the nose end o the stalk member, The diameter of the stalk member underlying each flange element is selected to provide an annulaL f ree ~pace . ~ between the inner surface oiE the ski rt of the .

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~t~ 8 associated flange element and the stalk member of ~uf~icient dimension as to allow said skirt portion to collapse into and occupy said space upon in~ertion of the earplug into the ear canal.

Bri~f Descri~tion of the ~L~

The drawing forming part hereof is a schematic~ diagrammatic longitudinal sectional view o~ ,an earplug in accordance with the invention, including various preferred embodiments thereof.

Reference being made to the drawing hereof, the earplug of the invention broadly comprises a stalk member 1 and an arra~ of at least three rearwardly oriented and spaced apart flange elements 10, 20 and 30, each being o~ generally circular cross section. Preferably, each flange element of the array extends rearwardly from its point of attachment to the stalk member 1 in a convexly arcuate manner and, most preferably, will be of generally hemispherical conformationO By "generally hemispherical" it is meant that the flange element deflnes no less than about 45% and no more than about 55% of a chordally sectioned hollow spherical body whose external surface is, at essentially all points thereon, substantially equidistant from its single geometric center. The earplug of the invention can be fabricated by any suitable polymer molding technique~ such as by injeotion molding thereof. An essential to the attainment of the benef its of the invention is the selection of the resilient polymeric material utilized in the fabrication of at least the skirts 12, 22 and 3Z o~ flange element~ 10, 20 and 30. Said -- _ . _ . .

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~ '7~3 material should have a Shore A Durometer hardness value (by the technique of ASTM ~240-81) of be~ween about 10 and about 90 and, preferably, of between about 30 and about 60. The stalk member 1 can, of course, be composed of a resilient polymeric material of the same type employed for thle flange skirts 12, 22 and 32 elements or, if desired, can be composed of a resilient polymeric material having a somewhat higher Shore A Durometer hardness value of, say, up to about 100. In one preferred embodiment of the invention, he material of construction of the stalk member 1 will have a Shore A Durometer hardness value of between about 50 and about 70. In another pre~erred embodiment of the inven~ion, however, for purpose~ of ea~y fabrication, lt will be preferred to utili~e a single polymeric material for the entirety of the constructivn.

Obviously, there are many known resilient polymeric materials which may be utiliz~d effectively in the fabrica~ion of the earplugs of the invention. For instance, natural rubber, neoprene rubber, SBR rubber, silicone rubber, EPDM rubber, polybutadiene rubber/ polyurethane elastomers, ethylene vinyl acetate elastomer~, elastomers based on acrylic acid precursors and vin~l halide polymers are all generally suitable materials of construction which can generally be procured from commercial sources with the necessary Shore A Durometer values or whlch can be suitably compounded (such as by internal and~or external plasticizing thereof) so as to confer the necessary hardness values thereto. Particularly preferred polymeric materials are the thermoplastic silicone rubber compositions such as exemplified by a family of thermoplastic injection moldable elastomers sold under the trademark, C-FL~ ~, Concept Polymer Technolo~ies, Inc., Clearwater, Florida ~hese ~ilicone rubber compositions are available in a considerable range of Shore A
Durometer hardness values, can be thermally formed into ':

intricate shapes by any conventional thermoplastic moldiny technique and the wares produced there~rom can generally be sterili~ed or cleansed without degradation thereo~. Another preferred materlal of construction of the earplug~ of the invention is a thermoplastic SBR block copolymer such as produced and ~old in a number of grades under the trade marlc, KRATON, by Shell Chemical Company, Synthetic Rubber Dlvision, NY, NY.

The first flange element 10 extellds outwardly and rearwardly froM the nose end 3 of stalk member 1, thereby to deEine a uni~ormly thin skirt 12 which is 3paced apart along its length from that portion of atalk member 1 lying thereunder. The second flange element 20 extends outwardly and rearwardly from a first intermediate location along the length of stalk member 1, thereby to define a uniformly thin skirt 22 which 1~ spaced apart along its length from that portion o~ stalk member 1 lying thereunder. Similarly, the third ~lange element 30 extends outwardly and rearwardly from a second intermediate location along the length of stalk member 1, thereby to define a uniformly thin skirt 32 which is spaced apart along its length from that portion o~ stalk member 1 lying thereunder. AS w111 be noted from the drawin~, the root portions 16, 26 and 36 of flange skirts 12, 22 and 32 respectively, ln other words, the points of junature of the interior ~urfaces of said skirts with the stalk member 1, are preferably con~ormed such a~ to provide minimum radiusing therebetween, consistent with good molding practices, thereb~ to mlnimize thickening and consequential stif~ening of the material of construction at said points. This design feature of the construction not only assures that the skirt~ 12, 22 and 32 are afforded maximum flexibility at said root portions, but also provides the skirts 12, 22 and 32 with a .: . .

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desirable "over center" eversion capability whereby each skirt can be readily manipulated 80 as to be everted ~rom its normally rearwardly directed orientation to a forwardly directed orientation. When so forwardly everted, the interior ~urfaces of said skirts and the portions of the stalk member 1 normally underlying said skirts are expolsed, thereby affording the user with the ability to readily inspect and/or cleanse areas o~ the earplug normally hidden from viewO

It is also to be noted that the diameters of the hollow flange elements 10, 20 and 30 increase ~erially and that, in a preferred embodiment of the invention, said elements are spaced along the length of stalk member 1 such that, in the finished earplug, a single stra~ght line of construction, L, can be drawn so as to be in at least point contact with all flange elementæ
of the array. In this pr~ferred embodiment, said diameters and ~pacing are also selected such that the half-angle 0 defined between said line of construction L and the forwardly extended centerline CL of the stalk member 1 will re~ide within the range of between 10 and 16, the preferred range for the half-angle e being between about 12 and about 14~ By adherence to these dimensional criteria it i8 a~sured that the earplug constructed in accordance therewith will be utilizable by and effective for the great majority of the user population.
For instance~ where the half-angle ~ is 13, the flange elements are generally hemispherical and the radiu~ of the first flange element 10 is about 0.165 inch (4.19mm), it has been found that the earplug of the invention can produce acoustically : effective seal for up to 98% of the entire adult user population, including females~

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It will be apparent to those of skill ln the art that many of the functional benefits of the present invention arise, at least in part, because the flange elements of the con~truction are embued with the ability to r~esiliently deform, ln use, to the extent necessary under relatively small and e~sentilly linear forc~s exert~d by or refl~ected into the walls of the ear canal upon inserton of the ea~pl~g thereinto. Thus, there exists a complex interplay betwe~en the specific geometries and sizing of the elements of the ea,rplug construction taken in combination with the hardness(es) of the resilient polymeric material(s) of construction employed therefor. Accordingly, it i9 not only important that the material of construction employed for each of the skirts 12~ 22 and 32 have a Shore A Durometer hardness value of between about 10 and about 90, but it is also important that the thickness of each o~ said skirts 12, 22 and 32 fall within the range of from about 0.003 (0.20 mm) and about 0.050 inch (1.27 mm)~ While no hard and fast rule of construction can be ~et in this regard, generally speaking the softer the material of construction the greater can be the thickness o~ the skirt 12, 22 or 32. Where materials of construction fallin~ within the preferred range of Shore A
Durometer hardness value~ of between about 30 and about 60 are employed, it has been found that the benefits of the invention are gen4rally substantially forthcoming when the thickness uf each of the skirts 12, 22 and 32 is within the range of 0.030 inch ~0.76 mm) and 0DO12 inch (0.30 mm~. Obviously/ the proper balancing of thickness of each of the sklrts 12, 22 and 32 and the Shore A Durometer hardness value of the resilient polymeric material of construction thereof can be readily determined experimentally. In a pr~ferred embodiment of the invention, it has been found that a nominal thickness of about 0~020 inch (0.50 mm) of each of the skirts 12, 22 and 32 and the use . , .

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therefor of a resilient polymeric material of construction having a Shore A Durometer har~ness value of about 40 yields an earplug construction having an excellent overall combination of effective acoustic sealing and wearer comfort propertiesr As mentioned previously, the diameter of that portion of the stalk member underlying each of the skirts 12, 22 and 32 of the : flange elements 1~, 20 and 30, respectively, is selected such as to provide an annular free spac:e 11, 21 or 31 thereunder and into which free space said skirt i~ enabled to deflect during insertion of the earplug ~nto the ear canal. The specific dimensions of the annular free spaces 11, 21 and 31 are not particularly critical provided~ of course, that each be adequate to serve the ~oregoing function. It is, however, ~enerally desirable that each said annular free space have a dimen~ion thereacross, determined by subtracting the diameter of $he underlying stalk member f rom the internal diameter of the open end of the skirt and dividing the result by two, of at least twice the thickness of the particular ~kirt 1~, 22, or 32 disposed thereover. By ~annular free ~pace", it is meant that

2~ the annular space 11, 21 or 31 contain no element or material therein which would tend to obstruct or restrict ~he movement of the as~ocia~ed skirt thereinto.
Bearing the foregoing in mind, it is within the ambi~ of the invention to form the stalk member 1 of a single uni~orm diameter. Where this is done, however~ it will be obvious that due consideration of the annular f ree space underlying each : flange skirt will ordinarily dictate that the uniform diameter selected for the stalk member 1 will be based up~n consideration of the annular free space for the smallest skirt, ln other words, the skirt 12 of the nose flange element lOo Thus~ unless the contemplated constant diameter stalk member is formed ~rom a .

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'7~3 relatively stiff resilient polymeric material, ~ch as one having a Shore A Durometer hardness value of greater than about 50, it can be found that the re~ulting earplug construction can be somewhat flaccid along the stalk member 1 and that ~aid stalk member does not provide ~ufficient support for the ~econd and third flange element~ 20 and 30 as to permit them to be readily inserted into the ear canal solely by manipulation oP the ~talk member. For these rea~ons, then, ~t is generally preferred that the diameter of the ~talk member 1, particularly where it i8 formed of a matexial of construction having a Shore A Durometer ; hardness value of less than about 50, be progresslvely or serially increased rearwardly from flan~e element to flange : el~ment, thereby to progressively or serially stiffen that portion of said member supporting the flan~e el~ments thereon~

In order tha the earplugs of the invention can be readily inserted and removed f rom the ear canal, it is desirable that the stalk member 1 extend rearwardly to any convenient length beyond the trailing edge 34 of the rearmost flange elemen 30 such that the rearmost portion thereof defines a handle 42 to be readily grasped between the thumb and forefinger o~ the user.

It is often desirable to provide pairs of ~arplugs tethered together by means of a length of pliant cord~ Such a tethered earplug construction can serve to prevent accidential dropping or loss thereof. This can be of importance~ for lnstance, where the earplugs are to be utilized in an industrial food processin~
environment or in an environment wherein a dropped earplug would be likely to be so dirtied as to be rendered unusable or to be lost altogether. In order to provide such a tethered earplug constructionr the ~ree end 40 of stalk member 1 can be provided , ~2-with an axially oriented channel or aperture 41 of a ~ize adapted to receive the end of a length of a pliant cord (not shown) therein. Said cord can be ~ecured in the channel or aperture 41 by any suitable means, such as ~y solvent or thermal welding thereof or by use of a suitable adhesive or b~ use of a cord whose ends are of somewhat greater diameter than the diameter of the receiving ~hannel or aperture 41, thereby to cau~e the resilient polymeric material surrounding said channel or aperture 41 to resiliently grasp the cord ends in a secure manner. For further general detail~ relating to tethered earplug constructions reference may be had to ~uch literature as: U.S. Patent No. D-241,881~ to Peterson et alO ~ u. s. Patent No. 4,193,396, to Wacker; U~S. Patent No. 4,219,018, to Draper, Jr.; U.S. Patent No. D~245,202, to Asker~

Additionally, while earplugs in accordance with the present invention may, as hereinbefore indicated, be utilized as individual ear insertable wares, they may also be utilized as stopple elements of a hearing protector device comprising a generally U-shaped spring headband to the ~ree ends of whicb headband the ~topple elements are affixed in an inwardly directed manner. In this embodiment, the earplugs of the invention are inserted into the ear canals of the wearer and are maintained under the continuous inwardly directed biasing forc~s . of the spring headband. Further detail relatlng to hearing protectors of this general type can be had by reference to such lit~rature as U.S. Patent No. 4,461,290, to Gardner, JrO et al., or U.K. Patent Ilo. 1,355,052, to Metal Box Company, Limi~ed.

Utiliz ing the foregoing principles of construction and for illustrative, non-limiting exemplary purposes, a plurality o~
three-flange earplugs substantially conformin~ to the drawing -.
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hereof was produced by injection molding of a thermoplastic silicone rubber (C-FLE ~ elastomer) havLng a Shor~ A Duro~neter hardness value of about 40. Referring to the drawing, the dimensions of the earplugs so produced are set forth below:

Overall length of ~talk member 1 1.183 inches (30.05~n) Diameter of stalk member 1 at end 40 0~203 inch ( 5.15mm~
Diameter of stalk member 1 ~nderlying skirt 32 0.203 inch ( 5.1Smm) Diameter of stalk member 1 underlylng skirt 22 0~188 inch ( 4.78mm) Diamete r of stalk member 1 underlying skirt 12 0.134 inch ~ 3~40mm) Radius of hemispherical flange element 10 0.165 inch ( 4.19mm) Radius of hemispherical flange element ~o 0~203 inch ( 5.15mm) Radius of hemispherical flange element 30 Or255 inch ( 6.48mm) Axial length of hemispherical flange element 10 0.174 inch ( 4.42mm) Axial length of hemispherical flange element 20 0.206 inch ( 5~23mm) Axial length of hemispherical flange element 0.262 inch ( 6.65mm~
Thickness of skirts 12, 22 and 32, each 0.019 inch ( 0~48mm) Length~ nose 3 to nose 24 0.385 inch ( 9~78mm) Length, nose 3 to nose 34 0~649 inch ~16.48mm) ~ :

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Annular space 11 0.085 inch ( 2.16mm) Annular ~:pace 21 t).090 inch ( 2.28mm) Annular space 31 0.135 lnch ( 3.43mm) Half-angle ~ 13 ~he earplugs were tested in accordance with the test procedure of ANSI S3.19-1974, utilizing ten ~ubjects. In the first test series (hereinafter "l~aximum Comfort Testn) 'che subiects were instructed to insert the plugs into their ear canals only to the point of maxim-~m perceived wearer comfort.
In the second test series (hereinafter "Maximllm Attenuation Testn) the subjects were individually fitted by a trained technician to the point of maximum acoustic sealing of the ear canals by the plugs. ~he Maximum Comfort Test yielded an NRR
value of 22 wh~le the Maximum Attenuation ~est yielded an NRR
value of 25., During the course of the Maximum Comfort Test the subj ects were asked to assess the relative comfort of the f itted earplugs in accordance with the following scale:

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, HEARING PROTECTIVE DEVICE COMFORT RATING SCALE

Comfortable Comfortable Und~scided Uncomfortable Painful O 1 2 3 4 5 6 . . _ _ ~ g 10 The average comfort rating afforded the earplugs of the invention by the test subjects was about 3.

For comparative purposes, a similar test serie~ was carried out with the same cadre of te~t subjects utilizing a commercially available multiple flange earpl~g of the prior art. The Maximum Comfort ~est yielded an NRR value of only 16.
: The ~aximum Attenua~ion Test yielded an N~R value of about 23 The average comfort rating afforded these commercial.earplugs by the test subjects durin9 the course of the Maximum Comfort Test was about 4. --Another Maximum Comfort Test was carried out with the same cadre of test subjects utilizing yet another commercially available multiple flange earplug of the prior art. The NRR
value was about 13 and the average comfort rating accorded the earplugs was about 6.

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Slnce many embodiments, modifications and variations of the present invention may be made in view of the ~bove teachings without departing from the spir.it of the invention, it will be understood that, within the ~cope of the appended claims, the invention may be practiced othe.rwise than as specifically described here~nbefore.
What is claimed is:

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An earplug composed of a resilient polymeric material and comprising:
an elongate stalk member having a nose end;
a flange array comprising at least three hollow, rearwardly extending flange elements of substantial circular cross sections and of serially increasing diameters integrally affixed to said stalk member at spaced intervals along at least a portion of the length thereof, the flange element of the smallest diameter being located at said nose end;
each said flange element being of generally hemispherical shape, comprising a thin skirt having a substantially uniform thickness of between about 0.008 inch (0.20 mm) and about 0:050 inch (1.27 mm) and being composed of a resilient polymeric material of construction having a Shore A Durometer hardness value of between about 10 and about 90;
the diameter of each portion of said stalk member underlying each skirt being such as to define an annular free: space between the interior surface of said skirt and said stalk member.

2. The earplug of Claim 1 wherein the spacing of said flange elements and the diameters thereof are such that a straight line of construction can be drawn which is in at least point contact with each of the flange elements of the array and that said line of construction intersects the forwardly extended centerline of said stalk member to define a relatively shallow half-angle therebetween.

3. The earplug of Claim 2 wherein said half-angle is between about 10° and about 16°.

4. The earplug of Claim 2 wherein said half angle is between about 12° and about 14°.

5. The earplug of Claim 1 wherein said material of construction of each of said flange elements of said array has a Shore A Durometer hardness value of between about 30 and about 60.

6. The earplug of Claim 5 wherein the thickness of the skirt of each said flange element is between about 0.030 inch (0.76 mm) and about 0.012 inch (0.30 mm).

7. The earplug of Claim 1 wherein said material of construction of each said skirt has a Shore A Durometer hardness value of about 40 and wherein the thickness thereof is about 0.020 inch (0.50 mm).

8. The earplug of Claim 1 wherein the diameter of each portion of said stalk member underlying each skirt increases rearwardly from flange element to flange element.

9. The earplug of Claim 8 wherein the resilient polymeric material of construction of said stalk member has a Shore A
Durometer hardness value of less than about 50.

10. The earplug of Claim 1 wherein the resilient polymeric material of construction of said stalk member has a Shore A
Durometer hardness value of between about 50 and about 70.

11. The earplug of Claim 1 wherein the dimension across each annular free space is at least twice the thickness of the skirt associated therewith.

12. The earplug of Claim 1 wherein said stalk member extends rearwardly from the last of said flange elements to a sufficient length as to define handle means; by which to manipulate the earplug.

13. The earplug of Claim 12 wherein the free end of said stalk member comprises an axially oriented channel of a size adapted to receive therein an end of a length of a pliant cord acting as a tether therefor.

14. The earplug of Claim 1 wherein the junction of the interior portion of the skirt of each said flange element of the array with said stalk member is of minimum radius, thereby to minimize thickening of the material of construction at Raid junction and to confer to said skirt the capability of manual eversion thereof to a forwardly extending conformation, whereby the interior surface of said skirt and that portion of said stalk member underlying same are exposed.

15. The earplug of Claim 1 wherein each hollow, rearwardly extending flange element of said array is convexly arcuate.

16. The earplug of Claim 1 wherein each hollow, rearwardly extending flange element of said array is of generally hemispherical shape.

17. The earplug of Claim 1 composed of a thermoplastic silicone rubber.

18. The earplug of Claim 1 wherein the spacing of said generally hemispherically shaped flange elements along said stalk member is such that the trailing edge of each skirt of each flange element is at least coplanar with respect to the nose end of the succeeding flange element thereto.

19. The earplug of Claim 1 wherein the spacing of said generally hemispherically shaped flange elements along said stalk member is such that the trailing edge of each skirt of each flange element slightly overlies the nose end of the succeeding flange element thereto.