1
in the Chemical laboratory Edifed by NORMAN V. STEERE, 140 Melbourne Ave., S.E. Minneapolis, Minn. 55414
1x1. Safety Manuals and Handbooks SAFETY GUIDE, Research Center, Monranfo Chemical Co., 800 N. Lindbergh Blvd., St. Louis Mo. 63147
f.
Editor's Note To help t,hose who may have responsibility for developing written safety for a laboratory, we COILtinue a series of excerpts from some laboratory safety manuals and handbooks. The series will include examples of detailed safety practices, basic safety paliciw, reasonable safety regulations, and flexible administrative proeednres. Table of contents is listed only to show extent of coverage and variations between organizations. Specific questions or comments about any manual or handbook excerpt should be directed to the contact persol, noted a t the end of the srticlc. Whether or not t,hey can provide copies of their manual will depend on the policy of their organizabion. I n 8. later issue, we plan to have a report of progress on the development of a eomprehensive laboratory safety manual by the Research and 1)evelapment Section of the Nat,ional Safety Council, one of three g r o u p active in laboratory safety. The Amet.ican Chemical Society and the National Fire Protection Assooiat,ion both have committees working on guidelines and standards that will be ilppropriate in a. laboratory safety manual. Purposes and activities of the three groups will be described here in the near future.
TABLE OF CONTENTS Bibliography Eating & Smoking Areas Electrical Wiring Evacuation Procedure Eye Protection General Safety Practices 1.oek O ~ t Procedure t konsanto Safety Policy Pressure Research Q & S Buildings Respiratory Protection Safet,y Department Function Safety Organization Chart Safety Shoes Solvent Handling Speaker System Tag Out Procedure Take Cover Procedure Waste Ilispoual
~pollsibility for safety. This is consistent with the principle of management which places responsibility for making decisions as close as pissible to the point where the action takes place. Action to achieve acceptable safety performenoe is a function of first line of supervision since they are closest to the people most subject to injury. However, responsibility for policy and for support of first line supervision rests wit,h bhe management of each research depertment,. The Safety Department is resnonsihle for the establishment and maintenance of t,he highest safety standards and will call on all levels of management to attain t,his objective
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the camplebe reaction period. This is particularly true when reactants form n two phasesystem and are exothermic. 7. Same reactions require an illduetion period, e.g., limiting concentrations or t,emperatnres may have to he reached before resction occurs. Readions should be heated gradually and under c ~ n t ~ l d l e d conditimm since the .ate of renetion is in general increased by raising the temperature. Adequate means should be readily available to bring a reaction under eontrol, e.g., sufficient cooling water, ice baths, proper fire extingoishers, ctc.
8. Solidific&m of reactants or products in an open system may lead to hazards from pressure build-u e.g., the solidification in condensers or I) ~ e s .
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GENERAL SAFETY PRACTICES FOR LABORATORIES 1. Safety should stsrt before experimentation by a survey of existing literature. The t.axicit,y and other haaards connected with the reactants and products should 'be investigated thoroughly before starting any laboratory reaction. The efTects of logical impurities on the safety aspects of the proposed react,ion should be considered. Safety information is available in the Library and from the Snfet,y I k partment. Another very valuable source of informctt,ion is the accumulated experience of t,he other research personnel both a t *,hislooation and company-wide. 2. The safety of other personnel in the laboratory should be considered as well ss the safet,y of the person running t,he reaction. Other personnel should be made cognizant of the nature of the react,ion to be carried out. 3. Before turning a. reaction over to another person he should be thoroughly instruded in the potential hazards and methods of counteracting such hazards.
4. Any reaction not completely described should he run on n small scale before attempt,ing full laboratory-scale reaction. Ilurirrg this phase of the experimentation the resction should tx presumed h a ~ a r d o i ~ s and the nertinont items of individual
SAFETY DEPARTMENT FUNCTIONS The Creve Coour Site Safeby Department xs a st,afTto the Administrative Director and General Offices Manager will, by teaching, counseling and advising, assist the members of line management of the divisions and of Office Management to fulfill t,o the highest degree their re-
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9. Glass equipment should be assembled carefully to avoid strains brought. about by increased temperat.nre and vibrations. Ball joints give greater freedom of movement than do standard tapered joints.
10. Joints, atopcocks, ebc. are not leak proof and provisions should be included for catching any material which may leak out. This is particularly t,rue when lenving a reaction overnight,. 11. Any vacuum, pressure or high tomperature distillation should be considered potentially hamrdous and the proper safety equipment such ns safety shields should be used.
12. Sufficient freeboard should be allawed when sizing equipment. to dlow for liquid expansion due to increased temperatwe. This is particularly trne in nowglass equipment when the volume of the reactants cannot be observed during all philses of the reaction.
13. I t should be borne in mind that the high boiling components tend to concentrate in the still pot and many s u b stances which are non-hasardons in diinte ooricent,rat,ian can be very hazardous i n concentrated forms. 14. With temperature sensitive matel.ial itshonld be remembered that when adding heat. to a reaction the temperature of the surface of the vessel may be considerablv higher than the temperature of the reaet.iorl mass in which case i t may be advisable to use a controlled temperature bath.
16. All electrical equipment shonld be grounded. in glass equipment is inherently dangerous as is the use of flabbottomed equipment in pressure and vacuum reactions. 6. Agitation sbould he employed during
16. Heating mantles are preferred over open flames or hot plates.
17. Sand trays should be placed u~ider (Catintccd o n page A S S Z )
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RESPIRATORY PROTECTION
distillation of flammable materials exceeding 2 liters.
18. Warning signs should be used as required. They should be removed when the hazard has been corrected or no longer exist,s. 19. All cont,ainers nor bottles containing chemicals shoold be clearly labeled. 20. Bottle carriers should he used when transporting glass bott,les containing hazrtrdoua chemicals (acids or other corrosive liquids) or any large glass bott.les (distilled water bottles.) 21. Always use robber gloves and goggles when t,rilnsferring corrosive liquids. 22. All gas cylinders must be firmly secured by means of safety clamps and straps or chains which are available from chemicd stockroom.
23. All electrical service cords should be in good condition, especially since most laboratories have metal partitions and furnitnre.
Respirators (both dust and fume) are available in the store-mom and are to be used its the need indicates. For more complete ~.espiratory proteotion both "all-service" Gas Masks and Scott Air-Psks are available from the storeroom in S-building and the shop area of N-building. Since Gas Masks are generally ineffective for concent,rations above 1 to 2%, the Scott Air-Pak wit,h its evlinder of su~oliedair is recommended for use if there is any chance of high concentration of toxic material. Scott Air-Paks, or other supplied air equipment must he used in abmospheres with low oxygen concentration. The cylinder of air is spproximately a 15-minute supply with heavy physical activity. Spare cylinder of sir are available in the storeroom and shop. Respiratory protection should he used when there is any likolihoad of a toxic gas or dust being present in levels above the TLV as set by ACGIII. Safety Department has dsta on file and is available for consultation. Before beginning an operation which is expected to require rospiratory protection, thesafety Department should first be consulted to be sure the planned coverage is adequate.
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EYE PROTECTION Safety glasses are minimum eye proteotion for the following areas: 1. All laboratories in Q-building including unit operations and sub-storerooms; all laboratories and pilot plant in Inorganic Lab; all laboratories aud green houses in Ag Lab.
Scott Air-Paks on the Safety Islands a w for emergency use ONLY. Units for routine or anticipated use must be obtained from the st,oreroom.
SAFETY SHOES
strip, relay boxes, etc. I t is further recommended that wiring for voltage above 110 v be done only by the Engineering Services group. Personnel in the laboratory and unit operat.ions should be free to make installations from existing outlets to and through variacs and to equipment, us in^ electrical cords, provided the cords are not, run on the floor. All laboratory electrical equipment should have threewire cords eit,her at time of purchase or s t t,hefirst opportunity for revision. Exceptions to this guide should be made only if the circuit is cheeked by the Engineering Services group prior to illntallat,ion by laborator). personnel, and inspected and approved after installation.
EATING AND SMOKING AREAS All Q, S, & W building laboratories are off limits for eating lunches. (This does not apply to machine-dispensed drinks or wrapped candy). A lunch room is provided. Laboratory glass is not approved for brewing coffee,heating soup or for any food or beverage use. Smoking is no1 pemitted in any of the following areas: Laboratory halls, pilot plant, stockroom and solvent storage. Unit Operations, all four floors, drum storage room and freight elevator. All sub-storerooms and solvent substorerooms. Ground level where "NO SA'IOKING" signs are posted.
2. All analytical laborabories.
The following areas are designated as safety shoe sreas for those people regularly working there:
Ground level-Group storage area and where "NO SMOKING" signs are posted.
3. Shop areas.
1. Shops
4. Chemical & solvent stores area.
2. Unit Operations labs
Solvent storage areas on first floor, paint shop on gmund floor, storage area 5-402 and freight elevator.
5. W-building laboratories, operating corridors.
cells
and
6. Waste neutralisation building. While safety glasses are not required a t laboratory desks, in halls or offices, their use is encouraged. Other areas may he designated as "Safety Glasses" areas if a hazard develops. More complete eye protection is required for extra. hazardous operations, for example; chipping, grinding, etc., either eover goggles, or safety glasses plus a full face shield are required. For handling strong acid, alkalis, etc., full cover (splash proof) goggles are required. All items listed above are available from the storerooms. Prescription safety glasses are obtained through the consulting optomet,rist who is in R-building a n the first and third Thursdays of each month from 1:00 p.m. to 4:00 p.m. He is also available a t these times to adjust any safety glasses whether prescription or not. For prescription safet,y glasses the employee bears the cost of obtaining the prescription and the ilivision pays the cost of the glasses.
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3. Cells, Corridors and Clave Shops 4. Shipping, Receiving & Stores
Safety shoes are furnished by the divisions for Lheir employes regularly working in the above areas. Other sreas may be deemed safety shoe areas by division management and shoes furnished a t their option. Wearing of safety shoes is recommended for all areas and safety show may be purchased through the storeroom on personal purchase account. Canvas or open sport shoes are not. acceptable for experimental areas.
Cells & operating conidom. storage areas.
Solvent
Drum storage area. Smoking is permissible in halls (except laboratory halls in N-bldg.) offices, lobbies and on passenger elevators. Smoking may be withdrawn in added areas depending on evaluation of, or change in occupancy. Control of smoking in laboratories is left to the oceupilnts. When operations are such that smoking is a risk, signs provided are to be posted on all doors signifying"N0 SMOIUNG."
PRESSURE RESEARCH ELECTRICAL WIRING Inst,allation of all t,ypes of electrical wiring by individual research groups may result in some sub-standard installat,ions with attendant hazards. To avoid this, only qualified electricians from the Engineering Services group will make alteration3 or additions to the building wiring. This includes all switch gear in the electrical cabinets and all permanent. installat,ions such as conduit, wire-mould
(A)
Q & S BUILDING
Research requiring pressure is st,rongly discouraged in the laboratories. The cells in the W-building are the designated areas for pressure research and should be used. Exceptions to the policy are on a cme basis with approval by an Assistant (Continued o n page A884)
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Ilirector in consultation with the Safety Ilepartment and a third person skilled in pressure research. I n general, for presw r e work iu laboratories, the following conditions will be necessary:
cedures developed by the Advanced Technology Laboratory. Vessels of undetermined chsracteristics are to he evaluated prior to use, including x-ray and/or ultrasonic tests where applicable.
For N-building see Inorganic Research Laboratory safety policies.
2. Drum Storage and Dispensing Areas Drums of flammables are stored in the X-building drum area, the Q Unit Operations storage room and the S-building solvent area.
1. No erplomtory pressure reactions are accept,able for lab modules.
3. Elevators
2. Reaction is well known as to energy re-
T1.nnsport,ation of flammable solvents is t,ohe hy freight elevators only.
lease, stability of materials involved, means of control, etc., and is either not exothermic or is readily and positively controlled.
4. Grounding
3. Volume under pressure is small500 ce. maximum.
100
6. Relief valve or roptwe disc must be used on all pressure equipment (reactors, receivel.~,etc.), and these must be set not over 125% of normal procesn pressure. Rolief devices must, vent int,o hood opening, must be properly sized for equipment to be vented, and have adequately sized discharge piping.
7. Pressure vesselr must. be tested prior to use and retested a t periodic intervals, consistent with usage, and following pro-
300 400
500
VOI of Reactor-Mi
5. Containers
4. Pressure to volume relations falls under att,ached curve with maximum pressure 1000 psig.
5. Pressure equipment is rated for 5 times anticipated pressure.
200
All drums for dispensing must be grounded and contninel.~also must be grounded t,o the drum when beingfilled.
SOLVENT HANDLING 1. Limitations By agreement with the Insurance carrier each laboratory module is limited to:
20 gallons oi flammable solvent in ~ a i e t y C&11S.
20 liters of flammable solvent in 1 liter glass bdtles-5 liters per experiment. Areas where exceptions to this limit are necessary must be provided with special fire protection above that normally provided.
Safety. cans and 1 liter glass bottles we t,he only approved containers for laboratmies. Other t,ypes of containers may be kept in the solvent sub-storeroom subject t,o the limitnt,imof space.
6. Acetone System
A piped-in Acetone System is provided to each solvent suh-storel.oom in Q-building. Cunt.ainers must be gt.onuded to the Acetune system before being filled. Any atmolmalit,ies of opemtion or indication. of leaks should be reported to the s t o w room immediately. SPEAKER SYSTEM The speaker system in the Q, R, S, N and W buildings is for emergency announcements only. Emergency is defined as a situat,ion involving injury or potential injwy to person~~el or property damage in the Research Center. Exceptions to this are only for purposes of testing the system or for allnonncing a test of other emergency mstems and will usnally be done after
WASTE DISPOSAL General
Waste disposal is a necessary task m-hich requires individual thought, cooperstion and ellort t o get. t,he job done saiely. The following idems give t,he usual mode of disposal. If iu doubt as t.o the proper method or in need of assistance, please check with your group leader or bhe Safety Ikpartment.
Waste Papw is disposed of via the waste baskets. All waste paper is burned in our incinerator for security reasons. NOTE: I h not thmw other materials in waste baskets where janitors or power house personnel may be injured. Examples: broken glass, pressurized spray ca1,s. Broken Glass and Arm-Toxic, ATonFlammable Solids are disposed of via the small yellow plsst,ic containers which are provided under the sinks in all laboratory
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modules. Larger containers which are marked for these materials are available in sub-storerooms. I n N-building broken glass is placed in red waste baskets. Water Soluble, Nonhazardous Materials may be flushed to the sewers via drains. Acids or Corrosive Malerials may be flushed to sewers via the drains with a t least 50 to 1dilution with water. Special precautions must he taken when disposing of strong acids like chlorosulfonic or perchloric acid. Check with the Safety Department if assistance is required. Nontozie Water Miscible Liquids such as acet,one or alcohol may be flushed to
the sewers via, the drains with a t least 50 to 1 dilution with water. Large quantities of water soluble organic solvents may also he drsposed of via the waste solvent drums as described below. Waste Soluent (Water-Immiscible Organic Soluents). These solvents are disposed of via. waste solvent cans and waste solvent drums. Wast,e solvent cans must be clearly marked safety cans. Waste solvent drums are located in the (1)solvent dispensing area in Q-building annex; (2) south of W-building; (3) outside Nbuilding pilot plant; and (4) in solvent room of V-building. Each gmup is responsible for depositing their waste solvent into the wastesolvent drums. Toxic Wastes. These materials are collected in the Toxic Dumpsters located near the loading dock west of Sbuilding and outside N-building Pilot Plant. If the hazard is too great for this type of disposal the Safety Department will advise as to the method to be used. Corrosive materials, including corrosive waste solvent, may be disposed of via. the Toxic Dumpster. NOTE: All material placed in the Toxic Dumpster must he properly labeled and packed in a. manner to reduce the chance of breakage. Proper labels includes the following: 1. Nameof material 2. Responsibleperson 3. Building, Cab. No. and Station No. P p p h o r i e Materials or Active Metals. These materials will he handled and labeled in the same manner as the Toxic materials. Toxic or Obnozious Gases. All toxic gases, including toxic vacuum pump exhausts, must he exhausted through hoods. These should be destroyed a t the source, if possible, by scrubbing, sdsorption, reaction or burning. Radioactive Materials. These materials must be disposed of according to AEC procedures a8 specified in AEC Rules and Regulations, Title 10, Paragraphs 20.30120.305. (See the Safety Department for these documents.) (Continued on page A886) Volume
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EVACUATION PROCEDURE If an adverse condition, such as fire, toxic gas, etc., arises in an area it may be necessary to evacuate all personnel from t,he area. involved. Such an evacuation will be announced over t,he P.A. system or by the Emergency Team in the area, or by the horn alarm in V-building. The following routes and evacnation areas have been set u p to regulate the flow of tr&c so that the evacuat,ion is quick and orderly. I t may be necessary, in some instances, t,o change or detour these routes to avoid congestion a t the site of the emergency or to circumvent the hazard. You will be advised of any changes over t,he P.A. system or by an emergency t,esm member a t the time of the emergency. You will also be advised of the urgency of the evacuxt,ian over the P.A. system. This will regulate the timing youmay have to shut ORequipment in order to leave i t in a safe sbate. If equipment is left in operation and needs attention, be sure to pass thiv word on to your Evacuation Area Leader. As possible, the Emergency Teams will check to make sure that everyone is safe and out of their area and to see if everybhing in t,he labs is normal. The first person to arrive a t a. door should hold i t open for others. NOTE: I n some cases these routes nre different far Evacuation and Take Cover. I n general for Evacuation the Ezterior stairways are used, and for Take Cover theinterior stairways aareused. Open Stairways. The center ytairway near the elevator in N-building, +.hestairway immediately North of the passenger elevator in Q-building and the stairway immediately South of the passenger elevetor in S-building will be kept free from traffic during evacuation for use by the Emergency Squad.
TAG OUT PROCEDURE General Policy This procedure forrnalises the minimum to he fallowed by personnel safe while inspecting, cleaning, installing or repairing any mechanical, electrical, hydraulic or pressure equipment or service thereto, to prevent personal injury. Lockout with a combinst,ion lock supplied to personnel is the preferred method. See Lock Out Procedure.
Responsibility Each worker is responsible for "tagging out" all switches, valves or other control devices to equipment upon which he is going to work if starbup of the equipment might expose him t o danger. He is further responsible to remove the tag when he is finished and inform his supervisor of the condition of the work when he leaves the job. The enforcement of this procedure is the direct responsibility of the supervision of the department or group performing the work. T h i ~may involve more than one group. For example, the UOL snpervi-
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sion might be responsible for "tagging out" equipment for shut-down snd cleaning operations and the Engineering Services Section supervision for repairs and installations. The group leader using t,he equipment, or his designate, is responsible for "tagging out" equipment which is taken out of service for an extended period of time. When work is done by outside contractors or any person unfamiliar with this procedure or the equipment, t,he responsibi1it.y for safe practices and "tag out" lies with the hlonsanto supervisor in charge.
Procedure 1. A "Danger" tag with proper instruetions must he placed on the control device or devices of d l electrical, mechanical, hydraulic or pressure equipment by each worker who will be exposed to danger by equipment starbup during inspection, cleaning, adjustment,, repair or installation. All auxiliary equipment which creates a hazard should also be tagged out. These tags are mailable in the Chemical Stockroom, the substorerooms in W and Q-Buildings, area. ioreman's offices in S-Building and N-Building, and the U O L ATL supervisors' office. 2. The person using the tag will include
his name, phone number, and the date the tag wasplaced. 3. Each worker must remove his tag when his pert of the work is complete. He must report the complet,ion of his part of t,he job to his supervisor. The last worker to remove his t,ag must also report the completion of the work t,o the person requesting the work. 4. A worker's tag cannot be removed or t,he equipment operated without his authorization except in an emergency situation. I n these cases where the worker cannot he located, the person request,ing tho work and the worker's snpervisor must check the equipment and determine that it, is safe bo opcrate. They assume full responsibilit,y upon removal of the tag. 5. If s. worker leaves t,he labarittory or work area, for an extended period of time without removing his tag, he must inform his supervisor that he is leaving the equipment "t,agged out" and his reason for doing so. When he returns to t,he job he should check to see that t,he equip ment is still ~ r o p e r l ytsgged and the equip ment is in a safe condition before proceeding again wibh the work.
6. Equipment, cannot be tested until all workers have removed their tags.
LOCK OUT PROCEDURE General Policv This procedure formalize3 safe practices to be followed whenever locking out equipment or services for inspection, cleaning, installation or repair. This procedure must he followed to insure safe working conditions and prevent personal injury. Equipment to be worked on, which is not equipped to take a lock, must he tagged
Safety
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out of selviee.
See Tag Out Procedure.
Procedure and Responsibility Each workel. is respousible for physically locking out all equipment before sbarting his work a~signment,,if st,art-np of e q u i p ment endangers him. (See "Tag Out" procedure for minimum safety practices). H e will secure the loek, check with the supervisor using t,he equipment, to make certain t h a t it, is properly lacked and r e move the lock whcn finished. 'Tho enforcement, of t,his brocedure is t,he direct respoosihilit,y of the group - ~- performing .the w&k. The aven foreman will issue a comhinat,ion lock to esoh shop t,echniciitn. He will keep n lag of all ismes. The log will include tho technicians' name, the stamped ident,ificat,ion number, and t,he eamhins, tion of t,helock. Any group can secure locks for their own permanent "lack out" use. However, the Safety Direct~ormust, approve this use. The supe~uisorof the g r o q then becomes responsible for the lock and it,#use. When work is done by out,side eont r d o r s or ot.her persons uufamilisr wit,h this prucednrc or the cqnipment,, the responsibility for safe "lock out" praet,ices lies with the Monsanto supervisor in charge. All equipment fitted to accept a lock must be properly "locked out" before any work is begou on the equipment or services thereto. If more than one worker is assigned to the job, each worker must "lock out" the equipment with his own lack. The ares. foreman has locking bars which provide for sevei,al locks to be used on the same "lock out" switch. After (.he lock is in place, the switch or contml device must be tested to see if the "lack out" is safe and t,hat all hasardous auxiliary oquipment is also inoperable. The switch or control device must he in the "OK" or safe position after testing the "lock out". After completiar~af his portion of t,he job the worker will remove his lock. At, this time he will inform his supervisor that his portinn of the job is completed. Before the last lack is removed, replace all gur~rdsand safety interlocks and inspect equipment thoroughly to insure that s t a r e 11p will not cause personal injury or damage. Following inspect,ion, the last lack can be removed and the operation of the equipment, tested. The person rcmoving t,he last lock will inform the persou rorpesting the work and his own supervisor t,hat all locks have been removed. Removal of Locks in Emergency I f t,he equipment is needed and d l locks have not been removed, t,he person desking to use tho equipment will h m e to cont,act, the area foreman or the Group Leader in charge of the equipment to ident,ify (.he worker. The lock cannot be removed withoot the worker's aathorimtion linless i t is an emergency sit,uat,ion, (Continued on page A888)
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and the worker is known to have left the plant and cannot be located. The Group Leader in charge of the equipment, the worker's supervisor and the Safety Ilirector must be present when the lock is removed without the worker's aufhorization. All must be sure the equipment can be operated safely. (Excerpts reprinted with permission, The Safety Guide of the Research Center, Monsanto Chemical Co., 800 N . Lindbergh Blvd., St. Louis Mo. which was pvepared by I,. C. Weger who recently died suddenly.)
LABORATORY SAFE Explosion Proof Hot Plate*
*UL Listed for use in Class 1 , Group D hozordous orem
Thermolyne (Sybron Corp.) 2555 Kerper Blvd., Dubuque, Iowa 52001, has introduced a, hot plate which is classified as explosion praaf and is UL listed. I t is designed for use in Class 1 locations where flammable gas or vapors are present in sufficient quantities to create a h a ~ a r d . The Group D classification specifies atmospheres containing gasoline, hexane, naphtha, benzine, butane, propane, alcohol, acetone, benzol, lacquer solvent vapors or natural gas. This hot plate is so designed that if vapors should seep in and ignite from contact point sparks, no secondary external explosion would occur. Enclosure joints are sufficiently long to cool escaping gases to where they present no danger. Maximum operating temperature is 220°C (428'F). If, for any reason, the temperature should overrun the maximum, a limit thermostat would cut the unit off when the temperature reached 243'C (470'F). A thermometer well. 17/64 in. diameter bv 2'/" in. deeo. ~, &vides a mountine p w k c . t fc,r cir twr ~ l w t m m w t wor thern.0coulrle for arc l l r n r v 11111 plntr tenlprvnturv measurement. Integral thermostatic control provides feedback action to maintain east aluminum top plste temperature within 2'/n°C. Red vinyl covered steel is durable, corrosion resistant and easy to clean. For maximum safety, this hot plate is designed for permanent installrttion. Design features permit coontertop mounting and conduit hook-up.
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