US3854885A - Toxic agent leak detector - Google Patents

Abstract

An optical detector plug fitted with a detecting system and inserted through the wall of the shipping container housing packaged toxic chemical agents. The escaping chemical agents upon contacting the system causes a color change indicating the presence of the agent. Shipping personnel looking through the plug will see a positive test and avoid any possible danger of contacting the toxic agent without proper precautionary steps.

Description

Elnited States Paten [191 Fromm et a1.

TOXIC AGENT LEAK DETECTOR Inventors: Bernard W. Fromm, Baltimore;

Achille Silvestri, Bel Air; Arthur R.

Jones, Jr., Elkton, all of Md.

Assignee: The United States of America as represented by the Secretary of the Army, Washington, DC.

Filed: Sept. 3, 1970 -Appl. No.: 78,316

US. Cl. 23/254 R, 23/253 R, 23/230 L, 137/551, 137/559, 252/68, 252/408, 206/84 Int. Cl. G0ln 31/22 Field of Search 23/253, 254, 230, 232; 137/551, 559; 252/68, 408; 206/84 References Cited UNITED STATES PATENTS Murray et a1. 23/254 [4 1 Dec. 17, 1974 1,619,273 3/1927 Sargent 137/559 2,716,338 8/1955 Blinn 73/73 2,951,461 9/1960 Lockwood 116/114 Primary Examiner-Benjamin R. Padgett Assistant ExaminerE. A. Miller [57] ABSTRACT 3 Claims, 4 Drawing Figures PATENTEU SEC] 7 I974 Fig.4

INVENTORS Bernard M. Fromm Ach/l/e .Sfiyesfr/ Arthur R. Jones, Jr.

BY M

ATTORNEYS DEDICATORY CLAUSE The invention described herein may be manufac tured, used, and licensed by or for the Government for governmental'purposes without the payment to us of any royalty thereon.

This invention relates to detection of toxic agents.

Among the objects of this invention is to provide a structure which is inserted into a container housing various packaged chemicals.

A further object of this invention is to provide a structure serving as a detecting means whereby escape of toxic chemical agents can be readily indicated inside the exterior cover and thus preventing the opening of the cover and exposing the free chemical agents to the atmosphere.

A further object of this invention is to protect personnel where there has been a leakage of the chemical agents. v

Prior to this invention, a shipping container sheltering broken chemical receptacles could not be detected until the container was opened. Under these circumstances, handling personnel had to be properly protected with clothing i.e. masks and/or rubber suits, before dismantling the shipping container. An alternative method was to return the container with its contents to the processor for the removal of the toxic chemicals.

In accordance with our invention, a detector plug is visibility of the detecting system and that the head is a convex optically contoured surface external to the container.

The composition of the detector plug can be commercially available polymerized methyl methacrylate,

Lucite, or any transparent material possessing optical qualities.

The detector plug can be utilized with any shipping container enclosing various chemical munitions.

FIG. 1 is a perspective view partially in section of the detecting system, in accordance with the present invendetecting system, that. is, ablank portion and a chemifitted with the detecting system andproperly inserted through the wall of the outer enclosure housing the packaged chemical agents. Escaping chemical agents will contact the detecting system causing a color change indicating a positive test. The shipping personnel looking through the optical convex head of the plug will see the positive test and avoid any possible danger of physically contacting the leaking agents. Proper handling procedures i.e. protective clothing and decontamination, can then be instituted prior to removing the chemical agents. In the event there is no escaping agents, no special procedure is required and the chemical agents can be removed with safety.

The configuration of the receptacle covering the packaged toxic chemicals can be any standard or universally acceptable form. The composition'of the receptacle may be wood, wood by products, plastic .or metal. I

The detector plug of this invention comprises transparent plastic materials coated with a chemical detecting system which is in contact with the atmosphere surrounding the toxic chemical receptacles. The plug is cal detecting indicator.

FIG. 4 is a fragmentary partially in cross section of FIG. 2, illustrating the concavity in'the outer end of the cylindrical body.

Referring more in detail to thedrawings:

FIG. 1 describes the outer enclosure by numeral 10 with the detector plug 25. The exterior of said enclosure is formed by sides 12 and 14, a base 16, a top 18, rear 23 and-front 20. Within said enslosure are one or more packaged toxic chemicals 22.

The detecting plug 25, being boltshaped,'is contiguous with the sidesof the container as shown in FIG- 2.

The plug comprising a head 27, a threaded shank 29, a smooth cylindrical body 31, chemical detecting system 33 secured at theouter end of said cylindrical body, and said head havingan optical convex surface I 35. Said outer end of body 33 can be a flat surface or concavity 34, FIG. 4, in order to receive the hardened agar-agar disodium salt of diisonitrosoacetone detectinserted by its threaded section through the wall of the shipping container at any location of choice and may be installed at the factory prior to shipping or installed at the point of destination.

The invention comprises a container housing packaged toxicchemicals and an optical detector plug with a chemical detecting system secured on said plug extending into the interior of the container so that any leakage of the chemicals can be observed through the transparent plug by personnel. In the event of darkness or dimly lit areas, as experienced in combat areas, a flashlight can be employed to aid in illumination. I

The configuration of the detector plug can vary, however, it is critical that the diameter of the smooth shaft be not less than 0.375 inches in order to have sufficient ing system. The outer end of body 33 may also have a split system, as exemplified in FIG. 3, one side a blank 32 and the other side the chemical detector 30. The split system can be employed to contrast a slight color change from a negative to positive test. Threaded shank is disposed within the wall of container 14 and may extend inside the enclosure. The'head has a flat under surface which limits the inward movement of the plug and aids in forming a seal. With respect to the invention, the configuration of the side of the head is of little account since the configuration is a means outside the container to apply sufficient torque to the detector plug for 'no leakage between the sides of the plug and the wall of the enclosure.

A gasket ring, not shown, of a generally flat shape for wedging purposes may be placed between the flat under surface of the head and the contacting portion of the exterior of the enclosure to aid in the prevention of leaks. The material of said ring may be any construction not effected by temperature or chemical agents, for example, rubber, plastic or similar material.

One or more detector plugs may be installed in any location of choice in the enclosure. A receiving hole is made in the side of the enclosure in a configuration of non-congruency to the threaded shank so that material of wall must be displaced in order for the threaded shank to be installed thus preventing escape of the chemical agents. The receiving hole may be made by various known means -i.e., drill bits. The noncongruency provides an automatically self-sealing plug.

T The plug is threaded into the prepared hole and turn; ing motion is applied to the head to the plug to firmly seat the under surface-of the head against the wall of the enclosure.

The method of preparing the toxic chemical warfare nerve agent Q-ethyl S-diethylaminoethyl methylphosphonothiolate was the result of classified research and does not form-the inventive portion of this invention.

The method of ,p'roducing O-ethyl S- diethylaminoethyl methylphosphonothiolate the steps v v The of the sni'ooth I percent by weight of an etheral solution, diethyle'the'r,

of polydimethylsiloxane fluid, Dow Corning 200, and after evaporation of the ether thes'ildxan'e coating is sprayed with the detecting system a finely divided coniposition of disodium salt of 'diisonitrosoacetone, a mixture of [(C H NC l-l -CNOH with a salt selected from the groupconsisting of zinc thiocyanat'e and mercuric bromide, orfmetanil yellow.

Substantially one-half of the tip, HO. 3, is first coated with a commercial-household cement i.e. nitrocellulose comprising to a 50.0 ml of 0.4M sodium hydroxide solution was added to 100 ml aqueous solution containing 9. 17g (0.04 moles) potassium ethyl methylphosphonothiolate, and then adding 200 ml of an aqueous solution containing 3.44g (0.02 moles) of beta-chloroethyl .di-

ethylamine hydrochloride. The" solutions were mixed and allowed to stand for five minutes. The pH of the solution was between' 1'0.0 and 10.5. After minutes, 50

f ml of 0.04M acetic acid-was added. The pH dropped to 5. l'-5. The solution was adjusted and maintained at pH 1 10.5 and extracted with-diethyl ether. The extract was dried over anhydrous sodium sulfate and distilled yield ing O-ethyl -S"-diethy.laminoethylmethylpho'sphonothiolate. l

l The detecting systems with their preparation and cent agar-agar, while fluid, is poured into a' concavity base adhesive, then adhering theuntreatedsilica gel, blank, and then adding thecement to the remainingportion of the tip with subsequentadhering the nickel chloride treated silica gel,"chemical"detector.

The 3-5' percent diisonitrosoacetone in the 1-5 peratthe tip of the smooth body. The 'fluidiupon cooling forms a hardened mass for detecting purposes.

g EXAMPLE-1' a. A sealed enclosure comprising the detector plug with the'det'ectin'gsystem secured at the terminal and thereof positioned through the wall of said-enclosure whichhouses an openvessel containing the chemical warfare nervetoxicant G-agents of ethyl dimethylphosproportions described below are identical to those utilized in Examples l-3 for indicating the presence of the toxic agents. However, it isto be understood that other detecting systems canbe employed with the detector Plug of this invention. 7 l

The -vaporized compounds at or isopropyl methylphosphonofluoridate' can bedem onstratedby contacting detecting systems of '(a) mixaquantity of at least 5' micrograms of ethyl d imethylphosphoramidocyanidate fluoridateiThedetecting systemis the disodium salt of diisonitrosoacetone adhering-to ipolydimethylsiloxanez' I a The vaporized G-agents uponcontactingjthe diisonitrosoacetone causes achange from ayellowtola mature comprising 50-95 percent by weight of [(CzH3)2 NC H -CNOH and 50-5-percent by weight of a salt of zincjthiocyanate ormercuricbromide, with a'color change from yellow to magenta; '(b) the disodium salt of diisonitrosoacetone, with a color change from'yellow to magenta, (c) 3-5 percent by weight of disodium salt ofdiisonitrosoacetone in an aqueou solution comprising about l-S percent of agar-agar, which is structurally the'sulfuric estei'ofa linear galactan and is transparent, odorless, tasteless, soluble in hot water forming a stiff gel upon cooling, with a color change from yellow'to magenta. v e

'The vapors of at least 10 micrograms of bis(beta chlorethyUsulfide, mustard gas, a vesicant chemical warfare agent are indicated by contacting with (a) the,

and'rne rcuric bromideor 1-5 percent agar-agar containing 3-5 percent disodium salt of diisonitrosoace-- tone with a colorichange, from yellow to magentaindieating the presence of atgleast' 5 micrograms of the G 7 agents, P

sodium salt of m-(p-anilnophenylazo)benzene sulfonic acid witha color change-from yellow to red, (b) -95' 50-5 percent by-weight of a salt of zinc thiocyanate or mercuric bromide with a color change from yellow to magentaindicating the sulfide at a quantity of at least 7 5 micrograms. I v The test for O -ethyl S-diethylaminoethyl methylphosphonothiolate-is to saturate commercially available silica' gel, 'U.S. screen -200,, with an aqueous solution of 0.2 gm/SO .ml of nickel chloride (NiCl HiO), The saturated silica gel is dried in an oven at C until the water has volatilizedand' is colorless. Thepresence of vaporized O-ethyl S-diethylaminoethyl methylphosfrom yellow to .65 phonothiolate at a quantity of at least 5 m crograms causes the color to change from a colorless treated silica gel to a browncoloration.

phoramidocyanidate:or isopropylmethylphosphonogenta color. The "shipping personnel looking through the optical-head of said plugseeing the magenta color know the presence ofat least5 micrograms of the G- agents without any personal 'dang'er. 1

V b. The'enclosure as defined inla) supra, was employed with thejexception os substituting for the disodium salt of diisonitrosoacetone the detecting system a mixture of [(QlighNCJ-Lly-CNOH with'a salt selected from the group consisting of zinc thiocyanate EXAMPLEZ a."l'l1e sealed enclosure and method of observation was employed as defined-in Example 1(a), with the exception of substituting bis(beta chloro ethyDsulfide and sodium salt of m-(p-anilnophenylazo)benzene sulfonic acid, metanilyellow, for the G-agents and detecting system respectively, giving rise to a color changefrom yellow to red indicating the presence of the'sultide.

b. The sealed enclosureand method as defined inta) supra, was employed -v'vith' the exception of substituting for the salt m-(p anilnophenylazo) benzene sulfonic-a employed as defined in Example'l(a),'with the excep-' tion of substituting O-ethyl S-diethylamino'ethyl methylphosphonothiolate and silica gel treated with nickel chloride for the G-agents and detecting system respectively, with a color change from colorless to brown indicating the presence of the O-ethyl S- diethylaminoethyl methylphosphonothiolate.

We claim:

1. A structure comprising a sealed outer receptacle enclosing at least one inner container containing a vaporizable toxic chemical warfare agent selected from the group consisting of nerve agent and vesicant, and at least one solid transparent threaded detector plug sealingly projecting through at least one threaded aperture in a wall of said receptacle, said plug comprising a solid one-piece transparent material in the shape of a bolt having an enlarged head means for assembling and sealing same and an elongated cylindrical shaped partially threaded body extending therefrom with the end portion of said body containing a coating of chemical detecting material from the group consisting of [(C H NC H CNOH with zinc thiocyanate, [(C H NC H -CNOl-l with mercuric bromide, di-

sodium salt of diisonitrosoacetone, sodium salt of m-(panilinophenylazo) benzene sulfonic acid, and silica gel containing nickel chloride, which changes color upon contact of said chemical warfare agent whereby if agent leakage occurs the change in color of the said detecting material is visible through the said head means and the said body from outside the said sealed outer receptacle.

2. The structure according to claim 1 wherein said outer receptacle encloses also a plurality of inner containers containing other vaporizable toxic chemical warfare agents, and wherein a plurality of transparent detector plugs project into said receptacle with different said chemical detecting systems for color reaction change upon contact with said other vaporizable toxic chemical warfare agents.

3. The structure according to claim 1, wherein said plug includes a transparent head having an optical con- I vex outer surface.

Claims (3)

1. A STRUCTURE COMPRISING A SEALED OUTER RECEPTACLE ENCLOSING AT LAST ONE INNER CONTAINER CONTAINING A VAPORIZABLE TOXIC CHEMICAL WARFARE AGENT SELECTED FROM THE GROUP CONSISTING OF NERVE AGENT AND VESICANT, AND AT LEAST ONE SOLID TRANSPARENT THREADED DETECTOR PLUG SEALINGLY PROJECTING THROUGH AT LEAST ONE THREADED APERTURE IN A WALL OF SAID RECEPTACLE, SAID PLUG COMPRISING A SOLID ONE-PIECE TRANSPARENT MATERIAL IN THE SHAPE OF A BOLT HAVING AN ENLARGED HEAD MEANS FOR ASSEMBLING AND SEALING SAME AND AN ELONGATED CYLINDRICAL SHAPED PARTIALLY THREADED BODY EXTENDING THEREFROM WITH THE END PORTION OF SAID BODY CONTAINING A COATING OF CHEMICAL DETECTING MATERIAL FROM THE GROUP CONSISTING OF ((C2H3)2NC6H4)2CNOH WITH ZINC THIOCYANATE, ((C2H3)2NCH6H4)2-CNOH WITH MERCURIC BROMIDE, DISODIUM SALT OF DIISONITROSOACETONE, SODIUM SALT OF M-(P-ANILINOPHENYLAZO) BENZENE SULFONIC ACID, AND SILICA GEL CONTAINING NICKEL CHLORIDE, WHICH CHANGES COLOR UPON CONTACT OF SAID CHEMICAL WAFARE AGENT WHEREBY IF AGENT LEAKAGE OCCURS THE CHANGE IN COLOR OF THE SAID DETECTING MATERIAL IS VISIBLE THROUGH THE SAID HEAD MEANS AND THE SAID BODY FROM OUTSIDE THE SAID SEALED OUTER RECEPTACLE.

2. The structure according to claim 1 wherein said outer receptacle encloses also a plurality of inner containers containing other vaporizable toxic chemical warfare agents, and wherein a plurality of transparent detector plugs project into said receptacle with different said chemical detecting systems for color reaction change upon contact with said other vaporizable toxic chemical warfare agents.

3. The structure according to claim 1, wherein said plug includes a transparent head having an optical convex outer surface.

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