L I Q U E F I E D P E T R O L E U M G A S E S

1229 LPG-- I

Report of Committeeon Liquefied Petroleum Gases

H. V. Keepers, Uhairman Fire Prevention and Engineering Bureau of Texas, 1320 Mercantile Securities Bldg.

Dallas, Texas 75201

W. L. Wa l l s , t 8wretary National Fire Protection Association, 470 Atlantic Avenue, Boston, MA. 02210

$. A. Cederval l , Underwriters' Laboratories, Inc.

j . J . Crowe, Compressed Gas Assn., Inc. J . A. D a v e n p o r t , Factory Insurance Assn. w i l b u r n Dodge, Fire Marshals Assn. o f

North America W. H. Doyle, Simsbury, Ct. L. H. F l ande r s , Factory Mutual Research

Corp. H. J . Haiges , J r . , National Park Service E. J . H e r r o n , Grinnell Mutual Reinsurance

Company H. T. Jones , Ontario Department of Labour L. L. K e n n e y , International Association of

Fire Chiefs P. H. K r o m a y e r , American Iron & Steel

Institute Donald M a d d o c k , Fire Equipment Manu-

facturcrs Assn. J o h n T. M c K e n n a , J r . , American Gas

Assn. Sam R. Mon t~ ,omery , t Industrial Truck

Assn. E. A. Olsen, Compressed Gas Assn., Inc. R. E. Poe th ig , National LP-Gas Assn. Don S c h u l t z , National LP-Gas Aasn.

tNonvotin8.

F. E. Se l im, American Petroleum Institute E. C. S o m m e r , American Petroleum In-

stitute J a m e s E. S t o c k t o n , Fire Marshals Aasn. of

North America H. E. T h o m a s , National LP-Gns Assn. J . H. Wi t t e , Gas Vent Institute R o b e r t Zlegler , American Insurance As-

sociation

A l t e r n a t e s

J a m e s E. Bates , Fire Equipment Mann- facturers Assn. (Alternate to Donald Mad-

dock) A. E. Cichel l i , American Iron and Steel

Inst i tute (Alternate to P. H. Kromayer) W. H. J o h n s o n , National LP-Gas Assn.

(Alternate to R. E. Poethig, H. E. Thomas and Don Sehultz)

A. A. M u l l i k e n , J r . , American Petroleum Insti tute (Alternate to F. E. Sellm and E. C. Sommer)

F. E. R a d e m a c h e r , Fac tory ' Insurance Assn. (Alternate to J . A. Davenport)

A. Santo@, Factory Mutual Research Corp. (Altexnate to L. H. Flanders)

TM~ text represents the memberddp at the time the Committee was balloted on th~ text of this edition. Since that time, changes in the memberehip may ham occurred.

The report of the Committee on Liquefied Petroleum Gases is in two parts.

Part I submits a m e n d m e n t s to N F P A No. 58 - - 1972.

Part I has been submitted to Letter Ballot of the Committee which consists of 23 voting members. 21 members voted affirmatively. The Messrs. Maddock and Olsen did not return their ballots.

1230 LPG-2 AMENDMENTS TO NO. 5 8

P a r t H submits a m e n d m e n t s to N F P A No. 59 - - 1968.

Part H has been submitted to Letter Ballot of the Committee which consists of 23 voting members. 21 members voted affirmatively on the report as a whole. Mr. Selim voted negatively on Par. 240(c)(3). Mr. Davenport Voted negatively on Par. 731. The Messrs. Maddock and Olsen did not return their ballots.

Part I P r o p o s e d A m e n d m e n t s to

Standard for the Storage and Handling of Liquefied Petroleum Gases

NFPA No. 58 ~ 1972

1. Revise existing'Note to 1000 and relocate at end of Paragraph 1000 as follows:

For example , the lower f l ammab le l imits . . . r e m a i n d e r un. changed.

2. Revise 1120(b) as follows:

(b) M a r i n e and pipel ine terminals , na tu ra l gas processing plants, refineries or t ank farms ( " t ank f a r m " storage a t indus t r ia l lo- cat ions is covered by N F P A No. 58) *

*For LP-Gas installations (including refrigerated storage) at such facilities, it is recommended that ANSI B138.1--1972 (API Standard 2510), "The Design and Construction of Liquefied Petroleum Gas Installatiofis at Marine and Pipeline Terminals, Natural Gas Processing Plants, Refineries and Tank Farms," be applied. Available from the American Petroleum Institute, 1801 K Street N.W., Washington, D.C. 20006.

3. Revise 1130 as follows:

1130. Unless otherwise stated, the provisions of this s tandard shall not be app l i ed re t roact ively.

(a) and (b) U n c h a n g e d

4. Revise 1201 as follows:

1201. A p p r o v a l appl ies to the comple te system, or t o the indi- v idual componen t s . . . r ema inde r unchanged .

LIQUEFIED PETROLEUM GASES

1231 L P G - 3

5. Revise parenthetical expression in 7300 as Jollows:

(See 1000 and Appendix A for f lammable limits of the LP-Gases.)

6. Revise 1307 as"follows:

. .1301..The odorization provisions of 1300 shall be considered to be met by the use of 1.0 pound of ethyl mercaptan or 1.0 pound of thiophane (tetrahydrothiophene) per 10,00_0 gallons . . . remainder unchanged.

7. Revise 76 definition of, " D I S T R I B U T I N G P O I N T " by deleting "(see definition)" in the last sentence.

8. Revise 16 definition o"f "LP-GAS S E R V I C E S T A T I O N " as follows:.

LP-GAs SERVICE STATION. See DIsTRIBuTING POINT.

9. Revise 76 definition of " V A P 0 ' R I Z E R - B U R N E R " as"follows:

VAPORIZING-BuRNER (also called VAPORIZER-BuRNER and SELF- VAPORIZINO LIQUID BURNER). A burner containing an integral vaporizer which receives LP-Gas in liquid form and which uses par t of the heat generated by the burner to vaporize the liquid in the burner so that it is burned as a vapor.

lO. Revise 2103 as follows:

2103. Containers for general use shall not have individual water capacities greater than 120,000 gallons. Containers in service stations . . . remainder unchanged.

71. Revise 2130(a) as follows:

(a) Recessing connections into the container so that valves will not be struck if the container is dropped upon a flat surface, or,

12. Revise 2130(b) as"follows:

(b) A ventilated cap or collar capable of withstanding a blow from any direction equivalent to that of a 30-pound weight dropped four feet. Construction shall be such that the force of the blow will not be transmitted to the valve.

73. Revise 2201 as follows:

2201. Container appurtenances shall be fabricated of materials

LPG--4 AMENDMENTS TO NO. 58

suitable for LP-Gas service and resistant to the action of LP-Gas under service conditions. Cast iron shall not be used. Cast malleable or ductile iron is not considered as cast iron in this standard. The following also shall apply:

(a) Pressure containing metal parts of appurtenances, such as those listed in 2200, except fusible elements, shall be of steel, ductile (nodular) iron, malleable iron or brass. Ductile iron shall meet the requirements of ASTM A395-71 or A445-71 or equivalent and malleable iron the requirements of A S T M A47--68 or equivalent. Approved or listed liquid level gages are exempted from this pro- vision.

14. Add a new 2203 asJollows:

2203. Gaskets used to retain LP-Gas in containers shall be re- sistant to the action of LP-Gas. They shall be made of metal or other suitable material confined in metal having a melting point over 1500°F. or shall be protected against fire exposure, except that aluminum O-rings and spiral wound metal gaskets are acceptable. When a flange is opened, the gasket shall be replaced.

15. Add the Jollowing sentence to 2221.

Cylinder valve oudet connections on all D O T cylinders except those used for engine fuel, from which vapor can be withdrawn shall not be interchangeable with those used for liquid withdrawal.

16. Renumber existing Note to 2221 as 2221(a).

17. Revise reference in 232(0(1) to " ( A S T M B-88 - - 1973)"

18. Revise reference in 232(c)(2) to " A S T M B-280-71(a)"

19. Revise Table 2-3 as Jollows:

T a b l e 2 - 3 . F i l l i n g W i t h d r a w a l a n d E q u a l i z i n g C o n n e c t i o n s

Type of Use

Type of Container

Water Capaci ty Pounds of Containers Gallons

Conditions under which Container is Uecd

Connection" Use (Note I) : " F " - - Filling, " W " - - Withdrawal,

" E " - - Equalizing

Appurtenances to be provided (Note 2):

1. Positive (Manual) Shutoff Valve

2. Positive (Manual) Shutoff & In- ternal Excess Flow Check Valve

3. Positive (Manual) Shutoff & External Excess Flow Check Valve (Note 4)

4. Single Back Flow Cheek Valve

5. Positive (Manual) Shutoff & Internal Back Flow Check Valve

6. Excess Flow Check Valve & Back Flow Check Valve

7. Double Back Flow Cheek Valve

8. Quick Closing Internal Valve

Column Number

General Uses

DOT Cylinder Specifications

1 to 1,000 50 to 1,000

Replacement Filled a t or Exchange Point of Use

Outdoors Outdoors

F W E F W E

3* 3* 5* 5"

1 1 2

2.5 to 2,$5

~[hen Used Inside

Buildings

F W ' E

I I

~/ ~/ v ~

ASME

Up to 120,000

Filled a t Point of Use

Outdoors

F W E

6*

Used as Fuel on Vehicles

DOT or ASME

Any

Any

Replacement or Fixed

F [ W E

Portable 1 Cargo Tanks Tanks

ASME ASME

Any Any

Any Any

Trans- Trans- portat ion por ta t ion

of LP-Gns of LP-Gas

F I w E F W E

i

I. 7*

6

Note Number.

1234 LPG-6 AMENDMENTS TO NO. 58

20. Revise 2340 as follows:

2340. Pressure containing metal parts of valves (except appliance valves), including manual positive shutoff valves, excess-flow cheek valves, backflow check valves and remotely controlled valves (either manually or automatically operated) used in piping systems, shall be of steel, ductile (nodular) iron, malleable iron or brass. Ductile iron shall meet the requirements of ASTM A395-71 or A445-71 or equivalent and malleable iron the requirements of ASTM A47-68 or equivalent. All materials used, including valve seat discs, packing, seals, and diaphragms shall be resistant to the action of LP-Gas under service conditions.

21. Revise 2402 as foUows:

2402. Equipment shall be fabricated of materials suitable for LP-Gas service and resistant to the action of LP-Gas under service conditions. Pressure containing metal parts shall be of steel, ductile (nodular) iron, higher-strength gray iron or brass meeting the re- quirements of ASTM A395-71, A445-71 or A536-:72 (grade 60- 40-18 or 65--45-12), A47--68 or A126-71 (Class B or C), or equiv- alent. Cast iron shall not be used for strainers or flow indicators which shall comply with provisions for materials for construction of valves. (See 2340.) Aluminum or zinc may be used for approved regulators.

22. Revise heading of 243 as foUows:

243. Vaporizers, Tank Heaters and Vaporizing-Burners.

23. Revise 2434 as follows:

2434. Vaporizing-burners shah b e . . • remainder unchanged.

24. Revise 2434(a) as follows:

(a) The vaporizing-burner, o r . . . remainder unchanged.

25. Revise 2434(b) as follows:

(b) Vaporizing co i l s . . , remainder unchanged.

26. Revise 2434(c) as follows:

(c) The vaporizing section shall be protected by a hydrostatic relief valve, located where it will not be subjected to temperatures in excess of 1400F, and with a pressure setting such as to protect the

LIQUEFIED PETROLEUM GASES L P G - 7

components involved but not lower than 250 psig. The relief valve discharge shall be directed upward and away from the component parts of the vaporizing burner. Fusibleplugs shall not be used.

2Z Revise 2434(0 as,follows:

(e) Vaporizing-burners shall be provided with an automatic safety device to shut off the flow of gas to the main burner and pilot in the event the pilot is extinguished. See Prevention of Fire and Dust Explosions in Grain Elevators and Bulk Grain Handling Facilities, NFPA No. 61B, for ignition and combustion controls applicable to vaporizing-burners associated with grain dryers.

28. Revise 2470 and Table 2-5 as,follows:

2470. Final stage regulators (excluding appliance regulators) shall be equipped on the low pressure side with one or both of the following: (See 3141(b) for required protection from the elements which may be integral with the regulator.)

(a) A relief valve having a start-to-discharge pressure setting within limits specified in Table 2-5.

(b) A shutoff device that shuts the gas off at the inlet side when the downstream pressure reaches the overpressure limits specified in Table 2-5. Such a device shall not open to permit flow of gas until it has been manually reset.

Regulator Delivery Pressure in pslg"

1 or less Above 1, not over 3 Above 3

Table 2-5

Relief Valve Start-to-Discharge Pressure Setting, % of Regulator Del ivery Pressure •

Min imum Maximum

17o% 300% 140% 250°/0 12S% 250%

29. Revise 2522 as follows:

2522. Appliances using vaporizing-burners shall . . . remainder unchanged.

30. Add a new 2524(b) as -follows and renumber existing 2524(b) as 2524(c).

(b) Catalytic heating appliances shall be equipped with an ap- proved automatic device to shut off the flow of gas in the event of combustion failure.

1 2 3 6 -" L P G - 8 AMENDMENTS TO NO. 58

31. In 2524, change reference to "2524(a) and (b) ''~ to "2524(a) th rough (c) ."

3Z Revise Table 3-1 as follows:

Table 3-I Water Capacity Minimum Distances Per C, ontalner Containers Between Aboveground

Gallons Underground Aboveground Containers Less than 125 10 feet None None (Note (a)) (Note(b)) 125 to 250 10 feet 10 feet None 251 toS00 10 feet 10 feet 3 feet 501 to 2,000 25 feet 25 feet 3 feet

(Note(c)) (Note(c)) 2,001 to 30,000 50 feet 50 feet 5 feet 30,001 to 70,000 50 feet 75 feet 70,001 to 90,000 50 feet 100 feet t ( ~ of sum of diameters 90,001 to 120,000 50 feet 125 feet of adjacent conthiners)

33. Revise .Note(a) to Table 3-1 as follows:

NOTE (a). At a consumer site, if the aggt~ate water capacity of a multi. container installation comprised of individual containers having a water capacity of less than 125 gallons is 501 gallons or more, the minimum d i s t ance . . , remainder unchanged.

34. Add a new 3113(a) as follows:

(a) T h e i n s t a l l a t i o n of. fire wa l l s shall be such as to minimize pocket ing of escaping LP-Gas , red i rec t ion of gas. f lames against conta iners and imped ing the app l i ca t ion of wate r to fire-exposed containers .

35. Revise 3115(c) as follows:

(c) Su i tab le means shall be used to p reven t the accumulation or flow of f l ammab le l iqu ids under ad j acen t LP-gas containers such as by dikes, d ivers ion curbs or grading .

36. Revise 3115(0 as follows:

(e) The minimum horizontal separation between aboveground LP-Oas containers and aboveground flammable liquid tanks shall be 20 .feet. Th i s provis ion shall not a p p l y when LP-Gas containers of 125 gal lons or less wate r capac i ty a re instal led ad jacen t to fuel oil

1237 LIQUEFIED PETROLEUM GASES L P G - 9

f

tanks of 550 gallons or less capacity (see 3116). No horizontal separation is required between aboveground LP-Gas containers and ,mderground flammable liquid tanks installed in accordance with ~IFPA No 30, Flammable and Combustible Liquids Code.

37. Add a new 3115( f ) and new Table 3-2 (see page LPG---IO)

(f) The minimum separation between LP-Gas containers and ox.vgen or gaseous hydrogen containers shall be in accordance with "~;al~le 3-2 except that lesser distances are permitted where protective structures such as fire walls, interrupt the line of sight between uninsulated poruons ot the oxygen or hydrogen containers and the LP.Oas containers (see 3113(a)). Also, see NFPA Nos. 50 and 51 for oxygen systems and NFPA No. 50A on gaseous hydrogen systems. The minimum separation between LP-Gas containers and liquefied hydrogen containers shall be in accordance with NFPA No. 50B.

38. Renumber existing 3115(f) and (g) as 3115(g) and (h).

39. Revise 3126(c) as follows:

(c) Containers shall be protected against corrosion for the soil conditions at the containersite by a method in accordance with good engineering practice. Precaution s h a l l . . , remainder unchanged.

40. Revise 3135(a) ( I) as follows:

(1) Except for D O T cylinders, excess flow or backflow check valves shall be located between the LP-Gas in the container and the shutoff valves, eitherinside the container, or at a point immediately outside where the line enters or leaves the container. If outside, installation shall be made so that any undue strain beyond the ex- cess flow or backflow check valve will not cause breakage between the container and such valve. On DOT cylinders, the excess flow valve where required may be located at the outlet of the cylinder shutoff valve.

41. Revise 3141 as.follows:

3141. Regulators shall be securely attached to container valves, containers, supporting standards or building walls.

(a) First stage regulators shall be either directly connected to the container shutoff valve or attached thereto by means of a suitable flexible connection.

(b) All regulators for outdoor installations, except regulators

LP-Gas Contalnefs Having An

T a b l e 3-2

Separation From OzyQen Containers Having An

AgKregate Water Aggregate capacity Capacity of of 400 CF* or le~

Separation From Gaseous Hydrogen C o n t a t n m Having An

Aggregate capacity Aggregate capacity of more than 400 of more than 20,000

CF* to 20,000 CF,* including CF*, including un- unconnected connected reserves, reserves.

Aggregate capacity of less than 400 CF*

Aggregate capacity Aggregate capacity of 400 CF* to of more than

3000 CF* 3000 CF*

1200 Gallons or l e~ None 20 Feet 25 Fee t

Over 1200 Gal. None 20 Feet 50 Fee t

500 Gals. or leas

Over 500 Gals.

None 10 Feet 25 Feet

None 25 Fee t 50 Feet

*Cubic feet measured a t 70°F and atmospheric p re~ure .

oo

LIQUEFIED PETROLEUM GASES

1,39 LPG-11

used for portable industrial applications, shall be designed, in- stalled, or protected so their Operation will not be affected by the elements (freezing rain, fleet, snow, ice, mud, or debris). This pro- tection may be integral with the regulator.

42. Revise 3192 as follows:

3192. The installation of vaporizers of the types covered by 243 is covered in Section 36 and of engine fuel vaporizers in Section 35. Integral vaporizing-burners, such . . . . remainder unchanged.

43. Revise 3223(a)3 as follows:

3. An excess flow valve properly 3135(a) (3).

sized in accordance with

44. Revise 3223(02 as follows:

2. An excess flow valve properly sized in 3135(a) (3).

accordance with

45. Revise 3312 as follows:

3312. Regulators, if used, shall be suitable for use with LP-Gas. Manifolds and fittings connecting containers to pressure regulator inlets shall be designed for at least 250 psig service pressure.

dO. Add a new 3316(a) as follows:

(a) Filling containers on roofs is prohibited. See 4010.

47. Revise 3317(b) as Jollows:

(b) The provisions of 3317 a r e . . , remainder unchanged.

48. Revise 3370 as follows:

3370. Containers having a maximum water capacity of 12 pounds (nominal five pounds LP-Gas capacity) may be used temporarily inside buildings for public exhibitions or demon- strations, including use in classroom demonstrations. If more than one such container is located in the same room, the containers shall be separated by at least 20 feet.

49. Revise 3372 as follows:

3372. Containers have a maximum water capacity of 21/~

1240 LPG-12 AMENDMENTS TO NO. 58

pounds (nominal 1 pound LP-Gas capacity) may be used in build. ings as part of approved self-contained torch assemblies or similar appliances other than mobile cooking appliances.

50. Revise 3560(a) as follows:

(a) The fuel system is leak free and the container(s) is not filled beyond the limits specified in Chapter 4.

51. Revise 3600 as follows: "

3600. This section applies to tile installation of vaporizing de- vices covered in 243. It does not apply to engine fuel vaporizers, or to integral vaporizing-burners s u c h . . , remainder unchanged.

5Z Revise 3620 by changing reference to 3626 to 3625.

53. Renumber existing Table 3-2 as 3-3 and change refererwe in 3625.

54. Delete 3626.

55. Renumber existing Table 3-3 as 3-4 and change reference in 3630(a).

56. Revise Table 3-4 (old 3-3) as Jollows:

Table 3-4

Container Water Capacity Minimum Distance .Required

500 gallons or l e s • 10 feet

501 to 1200 gallons 25 feet

Over 1200 gallons 50 feet

57. Revise heading o~ 364 as Jollows:

364. I n s t a l l a t i o n o f V a p o r i m ~ u g - B u r n e r s

58. Revise 3640 as foUows:

3640. Vaporizing-burners shall comply with 2434, and shall be installed as follows:

(a) Vaporizing-burners shall be installed outside of buildings. The minimum distance between any container and a vaporizing- burner shall be in accordance with Table 3-5.

(b) No change.

LIQUEFIED PETROLEUM GASES

-1241 LPG-13

Container Water Capacity

Table 3-5

Minimum Distance Required 500 gallons or less 10 feet

501 to 2000 gallons 25 feet Over 2000 gallons 50 feet

(c) Change "vaporizer" to "vaporizing section."

(d) Equipment utilizing vaporizing-burners shall be equipped with automatic devices both upstream and downstream of the vaporizing section. These dev i ce s . . , remainder unchanged.

(e) Change "vaporizer-burners" to "vaporizing-burners".

59." Renumber existing Table 3-5 as 3-6 and change reference in 3711 and 372?.

60. In Figure 3-1, change reference to Table 3-5 to Table 3-6.

61. Revise 3800(b) as follows:

(b) Commercial, industrial (including forklift trucks), construc- tion or public service vehicles such as trucks, sernitrailcrs, trailers, portable tar kettles, mobile laboratories and clinics.

62. Revise 3812(b) as follows:

(b) Fuel containers shall be securely mounted to prevent jarring loose and slipping or rotating, and the fastenings shall be designed and constructed to withstand without permanent visible deformation static loading in any direction equal to four times the weight of the container filled with fuel. When containers are mounted w i t h i n . . . remainder unchanged.

63. Add a new 3813 as follows and renumber existing 38?3, 381,4 and 3815 as 3814, 3815 and 3816.

3813. Containers installed on portable" tar kettles alongside the kettle, or on the vehicle frame, shall be protected against radiant or conveeted heat from open flame or other burners by the use of a heat shield or by the loeadon of the container(s) on the vehicle so as to prevent the temperature of the fuel in the container from becom- ing abnormally high. In addition, the following shall apply:

(a) Container location, mounting and protection shall comply with 3812(a), (b) and (c) except that the protection for DOT con-

1242 LPG-14 AMENDMENTS '1'O NO. 5 8

tainer valves need not be permanently attached to the container, however the protection.shall comply with 2130!a) and (b) ;

(b) Piping shall comply with 3816 (a), (b), (d), (e), (g), (h), and (i);

(c) Flexible connections shall comply with 2350, 2351 and 2352; (d) Container valves shall be closed when burner is not in use; (e) Containers shall not be refilled while burners are in use as

provided in 4061 (b) ;

64. Change referenc'e'i. "3814 (~ld.3813) from 38i3 to 3814.

65. Change reference in 3814(c) (old 3813(c) ) from 38"13 to 3814.

66. Revise 3815 (old 3814) as follows:

3815. Regulators, other than those used in engine fuel systems, shall c o m p l y . . , remainder unchanged.

67. Change reference in 3816 (old 3815) from 3815 to 3816.

68. Revise 3831(b) asJollows:

(b) All gas-fired heating appliances shaU :be equipped with safety shutoffs in accordance with 2524(a) except those covered in 3317(b).

69. Revise 3841 as follows: ,:

3841. Mobile units containing hotplates .and other cooking equipment, including mobile kitchens and Catering vehicles, shall be provided w i t h . . , remainder unchanged.

70. Revise 4010 asJollows: 4010. Liquid shall be transferred into containers only outdoors

or in structures especially designed for this purpose. Such structures constructed or converted for container filling after December 31, 1972 shall comply with Chapter 7. The transfer of fiquid into con- tainers on the roofs of structures is prohibited.

71. Revise 4060(c) as follows:. '.

(c) Sources of ignition, such as pilot lights, burners, electrical appliances, and engines, located on the vehicle being refueled shall be turned off during the filling of any LP-Gas container on the vehicle.

LIQUEFIED PETROLEUM GASES

1243 L P G - 1 5

72. Relocate existing 4222 and 4222(a) and (b) as a new 4061 and dool(a) and (b).

73. Add a new 5103 as follows:

5103. Containers not connected for use shall not be stored on roofs.

74. Revise 5200 as follows:

5200. DOT specification cylinders with a maximum water capacity of 21/~ pounds, used with completely self-contained hand torches and similar applications, may be stored or displayed in a building frequented by the public. The quantity of LP-Gas shaft not exceed 200 pounds except as provided in 522.

75. Delete existing 5201.

76. Revise 6220(d) as follows:

(d) Pipe joints may be threaded, flanged, welded or brazed using fittings as specified i n 6220(c). While it is recognized that welded joints are preferred, it is not always practical or possible to use them. In addition, t h e . . , remainder unchanged.

77. Add a new 6223(a) and (b) as follows:

(a) Flexible connectors assembled from rubber hose and cou- plings installed after December 31, 1974, shall be permanendy marked to indicate the date of assembly of the flexible connector and the flexible portion of the connector shall be replaced within six years of the indicated date of assembly of the connector.

(b) The rubber hose portion of flexible connectors shaft be re- placed whenever a cargo unit is remounted on a different chassis, or whenever the cargo unit is repiped, if such repiping encompasses that portion of piping in which the connector is located, unless the remounting and/or" repiping is performed within one year of the date of assembly of the connector.

78. Revise 6500 as foUows:

6500. This section applies to the parking (except parking as- sociated with a liquid transfer operation) and garaging of vehicles used for the transportation of LP-Gas. Such vehicles include those used to carry portable containers (See Section 61) and those used to carry LP-Gas in cargo tanks (cargo vehicles, See Section 62).

79. Revise heading of 051 to read "Parking"

1244 LPG=16 AMENDMENTS TO NO. 58

80. Revise 6510 as follows:

6510. Vehicles carrying or containing LP-Oas parked . . . re- mainder unchanged.

81. Revise 6510(a) as Jollows:

(a) Vehicles, except i n . . . remainder unchanged.

82. Revise 6510(b) as follows::

(b) Vehicles shall not be parked in congested areas. Such vehicles may be parked off the street in uncongested areas if at least 50 feet from any building used for assembly, institutional, o r mul. tiple residential occupancy. This shall not prohibit the parking of vehicles carrying portable containers or cargo vehicles of 3500 gallons water c a p a c i t y . . , remainder unchanged.

83. Revise 6511 as.follows:

6511. Vehicles parked indoors . . , remainder unchanged.

84. Revise 6511(a) as follows:

(a) Cargo vehicles parked i n . . . remainder unchanged.

85. Adda new 6511(b) as follows:

(b) Vehicles used to carry portable containers shall not be moved into any public garage or building for parking until all portable containers have been removed from the vehicle.

86. Redesignate existing 6511(b) as 6511(c) and revise as follows:

(c) Vehicles carrying or containing LP-Guq are permitted to be parked . . , remainder unchanged.

87. Revise 6511(c)(4) (old 6511(b)(4) ) asJollows:

(4) Primary shutoff valves on cargo tanks and other LP-Gas containers on the vehicle (except propulsion engine fuel containers) are closed and delivery hose outlets plugged or capped to contain system pressure before the vehicle is moved inside. Primary shutoff valves on LP-Gas propulsion engine fuel containers shah be closed when the vehicle is parked.

8s. Reuse 0511(0(5); otd 051KO(o'), as fotlows:

(5) No LP-Gas container is located near.., remainder unchanged.

LIQUEFIED PETROLEUM GASES

1245 L P G - 1 7

89. Revise 6511(c)(6), old 6511(b)(6), as follows:

(6) LP-Gas containers are gaged or weighed to determine that they are not f i l l e d . . , remainder unchanged.

90. Revise 6512 as jfollows:

6512. Vehicles are permitted to be serviced . . . r emainder un- changed.

91. Revise 6512(a) as follows:

(a) W h e n it is necessary to take a vehicle into . . . remainder unchanged except change 6511 (b) to "6511 (a) or (c)".

92. Revise 6512(b) as follows:

(b) W h e n it is necessary to take a vehicle carrying or containing LP-Gas into any public garage or repair facility for service on the engine or chassis, the provisions of 6511(a) or (b) shall be . . . re- mainder unchanged.

93. Revise 6512(b)(2) as follows:

(2) P r imary shutoff valves on cargo tanks, portable containers and other LP-Gas containers installed on the vehicle (except propulsion engine fuel containers) are closed: LP-Gas liquid shall be . . . re- mainder unchanged.

94. Revise 6512(b) (3) asJollows:

(3) N o container shall be located n e a r . . , remainder unchanged.

95. Revise 6512(b)(4) as follows:

(4) LP-Oas containers shall be gaged or weighed to determine that they are not filled . . . . remainder unchanged.

96. Revise 6512(c) as follows:

(c) I f repair work or servicing is to be performed on a cargo tank system, all L P - O a s . . . remainder unchanged.

97. Revise C-101 as foUows:

C-101. Pressure vessel codes, following boiler safety relief valve practice, require that the safety relief valve start-to-discharge setting be the design pressure of the container. I n specifying safety relief valve capacity, however, they stipulate that this capaci ty be

1240 LPG-18 A M E N D M E N T S T O N O . 5 8 '

adequate to prevent the internal pressure from rising above 120 percent of the design pressure under fire exposure conditions.

98. In C-210(b) second sentence, change "should" to "shall".

99. In D-OlO first sentence, change "may, in general" to "shall." In second sentence, change re~erence fiom 3801 to 3810.

100. In D-111 third sentence, change "can" to "shall".

101. In D-130 second sentence, change "are not" to "shall not be."

102. In E-lOl(c), change "should" to "shall" in all four locations.

103. Revise E-230 as follows:

E-230. Due to the diversity of fixed liquid gages, and the many sizes (from DOT cylinders to 120,000 gallon ASME vessels) and types (vertical, horizontal, cylindrical and spherical) of containers in which gages are installed, it is not possible to tabulate the liquid levels atwhich such gages indicate the maximum permitted loading densities (see Table 4-1 and $125(b) ).

104. Revise E-231 as foUows:

E-231. The percentage of container capacity which these gages shall indicate is computed by use of the formula of E-201. The liquid level this gage indicates is obtained by applying t h i s . . , remainder unchanged.

LIQUEFIED PETROLEUM GASES 1247

LPG--19

Part II

proposed Amendments to Standard for the Storage and, Handling of

Liquefied petroleum Gases at Utility Gas Plants

: NFP~L No. 5 9 m 1968

I. Revise 110 as follows: " "'

110. The purpose of this standard is to outline methods for protection of persons and property by providing a standard of reference . . • remainder unchanged.

~. Correct a¢~ editorial error in 115 by changing "Paragraph 113" to"114".

8. Revise 1~ as follows:

12. Application of Standard 120. This standard applies to utility gas plants for the de-

sign . . • remainder unchanged.

121. Where existing plants, equipment, buildings, structures and installations meet the applicable design, fabrication or con- struction layout provisions of the edition of this standard in effect at the time of installation, they are permitted to be con- tinued in use provided they do not constitute a distinct hazard to life or adjoining property.

122. Existing 1~1 unchanged except to change "USA Standard Z106.1" to "ANSI Z106.1".

123. Existing 1 ~ unchanged except to change "USA Standard Z106.1" to "ANSI Z106.1".

$. Add a new 137 as follows:

137. The term "gas-air mixer" refers to a device, or system of piping and controls, which mixes LP-Gas vapor with air to pro- duce a mixed gas of certain heating vMue but not within the flammable range. Any gas-air mixer which is designed to pro- duce a mixture containing more than 85 percent air by volume shall be considered a combustion device not subject to the pro- visions of this standard.

1248 LPG-20 AMENDMENTS TO NO. 59 '

5. Revise 1~1 as follows:

141. The odorization provision of 140 shall be considered to be met by the use of 1.0 pound of ethyl mercaptan or 1.0 pound of thiophane (tetrahydrothiophene) per 10,000 gallons of LP-Gas. However , . . . remainder unchanged.

6. Replace 150(a), (b) and (c) with the following:

(a) Listing by Underwriters' Laboratories, Inc., or other nationally recognized testing laboratory, or,

(b) The authority having jurisdiction. .:.

7. Revise 160 as follows:

160. Where damage to liquefied petroleum gas systems from vehicular traffic is a possibility, precautions against such damage (such as warning signs or devices, or barricades) shall be taken (see ~91).

8. Change reference in 170 from "USA Standard C 1 - 1968" to "ANSI CI".

9. Revise 171 as follows:

171. Adequate lighting shall be provided to illuminate operat- ing facilities, such as walkways and essential control valves, and particularly loading and unloading facilities.

10. Change reference in I80 from "USA Standard C 1 - 1968" to "ANSI CI". "

11. Revise 181 as follows: "

181. Fixed electrical equipment oii LprGas carg0vehicles shall comply with the provisions of Chapter 6 of the Standard for the Storage and Handling of Liquefied Petroleum Gases, NFPA No. 58 (ANSI Z106.1).

I $. Revise 195 as follows:

195. Smoking shall be prohibited in the vicinity of LP-Gas facilities and suitable signs to that effect shall be displayed at each point of entry.

13. Revise Note 3 to Table I as follows:

~v'cntilation is considered adequate when provided in accordance with the provisions of this standard.

LIQUEFIED PETROLEUM GASES

1249 L P G - 2 1

I~. Revise Note $ to Table 1 by changing the reference from " U S A C1 - - 1968" to " A N S I C I " .

15. Delete 210(a).

I6. Add a reference to " ( S e e 121)" at the end of ~11.

17. Revise 220 as follows:

• 220. S h o p f a b r i c a t e d c~n t a ine r s for n o n r e f r i g e r a t e d s t o r a g e shall be in a c c o r d a n c e w i th T a b l e 2.

Table 2 For Oaecs with Vapor Pressure Minimum Design Preasure in pslg

in pslg at 100 F (37.8C) not ASME Code~ Section VIII, 1971 to Exceed Edition (Notes 1, 3)

80 100 (Note 2) 100 125 125 156 150 187 175 219 215 250

NOT~. 1. See Appendix C of NFPA No. 58 - - 1974 for information on earlier ASME or API-ASME Codes.

Ncer~. 2. New containers for 100 psig design pressure (or equivalent under earlier codes) not authorized after December 31, 1947.

NoT~ 3. Because of low soil temperature usually encountered, and the insulating effect of the earth, the average vapor pressure of products stored in underground containers will be materially lower than when stored aboveground. This reduction in actual operating pressure there- fore provides a substantial corrosion allowance for these containers when installed underground.

18. Revise ~ 1 as follows:

221. F i e l d - e r e c t e d n o n r e f r i g e r a t e d con t a ine r s sha l l be b u i l t in acco rdance w i t h a p p l i c a b l e p rov i s i ons of t h e 1971 e d i t i on of t h e A S M E Code , excep t t h a t c o n s t r u c t i o n us ing j o i n t efficiencies in Tab le U W 12, C o l u m n C, D i v i s i o n 1 is no t p e r m i t t e d .

19. Revise ~ 0 as follows:

240. N o n r e f r i g e r a t e d A b o v e g r o u n d C o n t a i n e r s

(a) Unchanged.

(b) C o n t a i n e r s sha l l be l o c a t e d in a c c o r d a n c e w i t h T a b l e

1250 LPG-22 AMENDMENTS TO NO. 59

3 with respect to the distance between containers and the distance between containers and the nearest important building or group of buildings not associated with the LP- Gas plant, or a line of adjoining property which may be built upon. '

Table $

Water ~ .p~m'~ ea,~h eontaine~

2,001 to 30,000 30,001 to 70,000

70,001 to 90,000 90,001 to 120,000 120,001 to 200,000 200,001 to 1,000,000 1,000,001 or more

Minimum Distanoes ,

Between eont~iuent in feet

5 of sum of diameters of adjacent containers

From container to h e a r s t ira. ~ . ~ , . t building or groul~ of b t t i / d ~ not mlaoc~,ted with the LP-Gas plant, or a line ~f adjoining property which

may be built upon.

50 75

100 125 200 300

4 0 0

t In heavily populated or congested are~, where .se~o.us mutual exposures between container(s) and adjacent propert,es prevail, ,t,m re~mmended that greater distances or specia, protection m accoraance wire gooa nre protection engineering practices be provided. Special protection may consist of mounding or burying containers, or providing fixed water spray or monitor nozzle pro- tection.

(c) If water for container fire protection is to be applied only by hose streams, the following shall apply:

(1) Containers shall be arranged into groups with each group limited to a maximum of six containers.

(2) Each group shall be separated from the nearest container in another group by a distance of at least 50 feet.

(3) Containers shall be oriented so tha t their longi- tudinal axes do not point toward other containers, vital process equipment, control rooms, any of the buildings cited m 240(b), loading stations and flammable liquid storage tanks.

(d) If water for container fire protection is to be applied by fixed monitor nozzles, the following shall a p p l y :

(1) Containers shall be arranged into groups with each group limited to a maximum of six containers.

(2) Each group shall be separated from the nearest con- tainer in another group by a distance of at least 25 feet.

LIQUEFIED PETROLEUM GASES

1251 L P G - 2 ~

(e) If water for container protection is to be applied by fixed, water spray pro tec t ion in compliance with NFPA. No. 15, Water Spray Fixed Systems, the following shall apply:

(1) Containers shall b e a r r a n g e d into groups with each group limited to a maximum of nine containers.

(2) Each group shall .be separated from the nearest container in another group by a distance of at least 25 feet.

(3) In the design of water spray fixed systems, the area of container surface to be protected may reflect portions of containers not likely to be subject t o fire exposure as deter- mined by good fire protection engineering practice.

(f) A container or containers with an aggrega te water capacity in excess of 120,000 gallons shall be located 100 feet . . . remainder offirst paragraph of existing ~,~O(c) un- changed.

Such a container or containers shall be 100 feet . . . remainder of second paragraph of existing ~$0(c) unchanged.

(g) Existing ~40(d) unchanged.

(h) Existing $40(e) unchanged.

~0. Revise ~1(c) bychanging " m a y " to "are permit ted to" .

~1. Revise ~$1(d) as follows:

(d) Containers shall be l o c a t e d . . . remainder unchanged.

$$. Revise ~4) (e) as follows:

(e) Containers shall be located . . . remainder of first sentence unchanged.

They shall be l o c a t e d . . , remainder of second sentence and rest of ~ I (e) unchanged.

~8. Revise ~1~ as follows:

244. Containers connected to a common manifold shall be in- stalled so tha t their maximum liquid filling levels present sub- stantially . . . remainder unchanged.

~4. Revise ~50(b) as follows:

(b) Supports for containers shkll be of solid masonry, concrete or steel. S t ructura l metal suppor t s are permit ted

1252 LPG--24 A M E N D M E N T S TO NO. 59

to be employed when they are protected against fire in an approved manner. Metal supports shall be protected against fire with a material having-a fire resistance rating of at least two hours. Steel skirts having only one opening 18 inches or less in diameter shall be protected in accordance with the preceding, but fireproofing need only be applied to the out- side of the skirt.

25. Revise 250(e) by changing "should" to "shall".

26. Revise 251 (c) as follows:

(c) Containersshall be set upon a firm foundation (firm earth is permitted to be used) and surrounded with earth or sand firmly tamped in place. Backfill shall be free of rocks or other abrasive materials. Provision shall be made to take care of settling and rotation.

27. Designate the Note to 251(e) as 251(f) and revise as.follows:•

(f) If the area above a container is to be used for purposes not prohibited by this standard, consideration shall be given to depth of cover and loads that may be imposed.

28. Revise 255 as follows:

255. To minimize the possibilities for trespassing and tamper- ing, the area which includes container appurtenances, pumping equipment and loading and unloading facilities, shall be pro- tected by one of the following methods:

(a) Enclosure with at least a 6-foot high industrial type fence unless otherwise adequately protected. There shall be at least two means of emergency access through the fenced or other enclosure.

(b) As an alternative to fencing the operating area, suit- able deviceswhich can be locked in place, shall be provided. Such devices, .when in place, shall effectively prevent un- authorized operation of any of the container appurtenances, system valves or equipment.

(c) Locks with frangible shanks shall be used.

29. Revise 282 by changing "may" to "is permitted to".

• 30. Editorially clarify Table ~ by moving "Underground Con- tainers" in the right hand column upwards in line with "Above- ground Containers."

LIQUEFIED PETROLEUM GASES 1253 LPG-25

M. Add a new ~9 as follows:

29. Loading and Unloading Facility Spacing

290. Loading and unloading connections shall be at least 75 feet from uncontrolled sources of ignition, process areas, control buildings, offices, shops and other occupied or important plant structures. This does not apply to structures or equipment directly associated with the transfer operation.

:291. The filling pipe inlet terminal shall not be located inside a building. Such terminals shall be located at least 25 feet from a container, shall be properly supported and protected from physical damage by vehicular movement, and shall be located at least-5 feet behind any barriers provided for such protection.

Revise 310(a) as follows:

(a) For pressures of 15 psig or more, use the 1971 edition of the ASME Code, Section VIII except that construction using joint efficiencies in Table UW 12, Column C, Division 1 is not permitted. Last sentence unchanged.

83. Revise reference in 310 (b) by changing date to I973 and change A P I address in footnote.

85. Revise 312 as follows:

312. When austenitic steels or nonferrous materials are used, API 620, Appendix Q shall be u s e d . . , remainder unchanged.

35. Delete 313

36. Revise 320(g) by changing "may" to "is permitted to".

37. Revise 330 as follows:

330. Refrigerated Aboveground Codtainers

(a) Unchanged (b) Containers shall be located in accordance with Table

5. z

xIn heaxdly populated or congested areas, where serious mutual exposures between container(s) and adjacent properties prevail, it is recommended ..t~t greater distances or special protection m accordan..ce with good fire pro~ectaon engineering practices be provided. Special protection may cons.m~ ox mounmug or burying containers, or providing fixed water spray or monitor nozme pro- tection.

1254 LPG-26 AMENDMENTS TO NO. 59

Table 5 ~ unchanged

(e) A container or containers with a n aggregate water capacity in excess of 120,000 gallons shall be located 100 f e e t . . , remainder offirst sentence unchanged.

Such a container or containers shall be 100 feet . remainder of second sentence and rest of 880(c) unchanged:

88. Revise 851 by changing "may" to "is permitted to".

89. Revise 3/~3 as ]allows:

343. Aboveground LP-Gas containers shall be inside a diked area except where spillage of hydrocarbon can be contained in a designated area within the plant si te by topography.

~,0. Revise 3]~3~ as follows:

3432. More than one container is permitted to be installed in a single diked area or topographical enclosure provided:

(a) Unchanged (b) Unchanged

(1) Unchanged (2) Unchanged

(c) Container foundations are constructed of concrete properly designed for fire exposure.

M. Revise ~ $ as follows:

3434. The walls of the dikes shall be not less than 5 feet in height. Where t o p o g r a p h y . . , remainder unchanged.

/~. Revise 357 as follows:

347. To minimize the possibilities for trespassing and tamper- ing, the area which includes container appurtenances, pumping equipment and loading and unloading facilities, shall be protected by one of the following methods:

(a) Enclosure with at least a 6-foot high industrial type fence unless otherwise adequately protected. There shall be at least two means of emergency access through the fenced or other enclosure.

(b) As an alternative to fencing the operating area, suit-

LIQUEFIED PETROLEUM GASES

1255 LPG-27

able devices which can be locked in place, shall be provided. Such devices, when in place, shall effectively prevent un- authorized operation of any of the container appurtenances, system valves or equipment.

(c) Locks with frangible shanks shall be used.

]j3. Revise 370 by changing "may be" to "is" in the next to the last line.

~ . Add a new 88 as follows:

38. Loading and Unloading Facility Spacing

380. Loading and unloading connections shall be at least 75 feet from uncontrolled sources of ignition, process areas, control buildings, offices, shops and other occupied or important plant structures. This does not apply to structures or equipment directly associated with the transfer operation.

381. The filling pipe inlet terminal shall not be located inside a building or diked area. Such terminals shall be located at least 25 feet from a container, shall be properly supported and pro- tected from physical damage by vehicular movement, and shall be located at least 5 feet behind any barriers provided for such pro- tection.

~ . Revise $10 as follows:

410. Piping shall be suitable for its intended use at the temperatures of the application and shall be designed for not less than the maximum pressure and for the minimum temperature to which it may be subjected. The temperature change occurring during the conversion from the gaseous to the liquid phase per- mits the use of several materials, each having its own specific utilization temperature range. The design and fabrication of piping systems shall be in accordance with ANSI B31.3, Petroleum Refinery Piping, 1973, except as modified by the pro- visions of this Section and any applicable Federal pipeline regulations.

/~. Revise $I~ as follows and delete Footnote 2

412. The use of cast iron valves, pipe and fittings shall be pro- hibited in piping carrying LP-Gas. This does not prohibit the use of container valves or fittings made of malleable or ductile iron if used within the limitations set forth in Paragraph 323.3 of ANSI B31.3 - - 1973.

1256 LPG-28 AMENDMENTS TO NO. 59

47. Revise 416 by changing "may" to "is permitted to".

48. Revise 4~7 by changing "may" to "are permitted to".

49. Revise .480 by changing "should" to "shall".

50. Revise 481 as follows:

431. Where practical, liquid manifold connections shall b e . . . remainder unchanged.

51. Delete existing 438 and 434

5~. Renumber existing 4841 as 488

63. Renumber existing 435 as 485 and revise as follows:

434. In the design of the liquid piping system, shutoff or block valves shall be installed to limit the volume of liquid that could be discharged in the vicinity of containers or important structures in the event of a liquid line failure. Automatically or remotely con- trolled valves, or both, of the fail-safe type, shall be used. The mechanism for such valves shall be provided with a secondary control equipped with a fusible release (not over 220°F melting point) which will cause the valve to close automatically in ease of fire. Such valves shall also be capable of being manually operated at the installed location. Such valves within 300 feet of a container or important structure shall be arranged to limit the quantity that could be discharged to a maximum of 300 cubic feet of liquid. In no case shall there be more than 150 feet be- tween valves on the same line within 300 feet of a container or" important structure.

65. Add a new 485 as follows:

435. In addition to the valving specified in 434, suitable safe- guards shall be provided to prevent the uncontrolled discharge of LP-Gas in the event of failure in the flexible connecting hose or swivel type piping, located as close as practicable to the points where connections are made between the flexible and fixed parts of the piping system, as follows:

(a) The connection, or connecting piping, into which the liquid or vapor is being transferred shall be equipped with:

(1) A back-flow check valve, or (2) An excess flow valve properly sized in accordance

with 422.

LIQUEFIED PETROLEUM GASES

1257 LPG-29

(b) The connection, or connecting piping, from which the liquid or vapor is being withdrawn shall be equipped with an excess flow valve properly sized in accordance with 422.

55. Delete ~37

56. In the next to the last line, editorially revise $$0 by adding a comma after "device" and deleting the colon.

57. Relocate ]~6 as ~$01 and revise as follows:

4401. Unlisted gauge glasses of the columnar type shall not be permitted.

58. Revise $$I as follows:

441. Refrigerated containers shall be equipped with a liquid level gauging device of approved design. A n . . . remainder un- changed.

59. Revise $5 as follows:

45. Hose Specifications for Nonrefrigerated LP-Gas.

60. Revise $50 as follows:

450. Hose shall be fabricated of materials that are resistant to the action of LP-Gas and shall be approved.

61. Revise $51 as follows:

451. Hose, hose connections and flexible connections shall comply with 451(a) and (b).

(a) Hose shall be designed for a minimum bursting pressure of 1,750 psig (350 psi working pressure) and shall be identified "LP-Gas" or "LPG" at not greater than 10-foot intervals.

(b) Hose assemblies, after the application of connections, shall be capable of withstanding a test pressure of not less than 700 psig.

6~. Delete 1e5~.

68. Revise $61 as follows:

461. Avoid the use of pits containing LP-Gas equipment. If pits axe u s e d . . , remainder unchanged.

1258 LPCr-30 AMENDMENTS TO NO: 59

64. Revise ~80 by incorporating the Note as new second sentence as follows:

If locks are used, they shall be of the frangible shank type.

65. Revise title of Section 5 as follows:

SECTION 5. VAPORIZERS AND GAS-AIR MIXING

66. Revise 5 ~ as follows:

522. Building or structural enclosures in which vaporizers and/or gas-air mixers are-installed shall be of lightweight non- combustible construction with nonload-bearing walls. If rooms containing such equipment are located within or attached to buildings in which LP Gases are not handled, i.e., control rooms, shops, boiler rooms, etc., the common walls shall be limited to no more than two in number, shall bedesigned to withstand a static pressure of at least 100 psf, have no doors or other communicating openings, and shall have a fire resistant rating of at least one hour. Such buildings or structural enclosures shall be ventilated to minimize the possibility of hazardous ac- cumulations of flammable vapors by a gravity system composed of a combination of wall openings near the floor line and roof ventilators. The ventilation rate shall be at least 1 efm of air per square foot of floor area.

67. Revise ~ 5~3 as follows:

523. A shutoff valve shall be installed on the liquid line to a vaporizer at least 50 feet away from the vaporizer or a building housing a vaporizer. : ,.

68. Delete

69. Revise

5~5

5S~ by changing " m a y " to."are permitted to" .

70. Revise 588I as follows:

5331. Such buildings or structural: enclosures in which vaporizers are installed shall be constructed and ventilated in accordance with 522.

71. Delete 585 and renumber existing 535 through 537 as 58~ through 586.

7~. Delete 538 and renumber existing 589 as 537.

LIQUEFIED PETROLEUM GASES

1259 LPG-31

75." A d d a new 5~ as follows: -~

54. Gas-Air Mixing

540. Gas-air mixers shall be designed for air, vapor and mix- ture pressures in accordance with good engineering design prac- tice. Piping materials shall be in accordance with Section 4 of this standard. Gas-air mixers shall be so designed as to prevent the accidental formation of a flammable mixture.

541. Gas-air mixers shall be equipped with safety interlocks on both the LP-Gas and air supply lines to shut down the system if flammable limits are approached. Gas mixing .control valves which provide tight shutoff of the LP-Gas and air supply lines when actuated by safety interlocks shall be considered as ac- ceptable shutdown devices. Such valves shall fail in closed position.

542. A means shall be provided to prevent air from entering mixed gas lines without LP-Gas being present.

543. A means, such as a check valve installed in the air supply line close to the mixer, shall be provided to prevent back-flow of gas into the air supply system.

544. Where it is possible for condensation to take place be- tween the vaporizer and the gas-air mixer, an interlock shall be provided to prevent LP-Gas liquid from entering the gas-air nnxer. This interlock shall be thermally actuated, liquid level actuated or actuated by another method which can be demon- strated to be effective.

545. Gas-air mixers which utilize the kinetic energy of the LP-Gas vapor to entrain air from the atmosphere, and are so designed that maximum air entrainment is less than 85 percent of the mixture, need not include the interlocks mentioned in 541 and 542, but shall be equipped with a check valve at the air in- take to prevent the escape of gas to atmosphere when shut down. Gas-air mixers of this type receiving air from a blower, com- pressor, or any source of air other than direct from atmosphere, shall include a means for preventing air without LP-Gas from entering the gas system.

546. Gas-air mixers may be installed in buildings or structural enclosures used exclusively for gas-air mixing or for vaporizing LP-Gas and mixing, provided that the vaporizer is not directly heated with open flame. Such buildings orstructural enclosures shall be constructed in accordance with 522.

1260 LPG-32 AMENDMENTS TONO. 59

74. Revise 611 as follows:

611. Each container relief device shall be plainly and per- manently marked with the pressure in pounds per square inch gauge at which the device is set to start to discharge, with the actual rate of discharge in cubic feet per minute of air at 60°F and 14.7 psia, and with the manufacturer's name and catalog number. For example, a safety relief valve marked "250-15,000 AIR" indicates that it is set to start to discharge at 250 psig and ~that its rate of discharge is 15,000 cubic feet per minute of air.

75. Incorporate the Note to 616 into 616 as additional sentences as foUows:

This exception is made to cover such arrangements as a three, way valve installed under two relief devices, each of which has the required rate of discharge. The installation shall allow either of the relief valves to be closed, but shall not allow both to be closed at the same time. In another arrangement, two separate relief valves are permitted to be installed with individual shutoff valves if the shutoff valve stems are mechanically interconnected in a manner which will allow full required flow from one relief valve at all times.

76. Revise 618 as follows:

618. Discharge lines from two or more relief devices located on the same unit, or similar lines from two or more different units, except those located on storage containers, are permitted to be run . . . remainder unchanged.

77. Revise 620 as follows:

620. Relief devices shall be tested for proper operation a t inter- vals not exceeding five (5). years.

78. Revise 685 as follows:

632. Container relief valves shall be set to start to discharge with relation to the design pressure of the container in accordance with Table 6.

1261 LIQUEFIED PETROLEUM GASES LPG-33

Table 6

Containers ..'. Minimum Maximum

All ASME Codes prior to the 1949 Edition, andthe 1949 Edition, paragraphs U-68 and U-69 • 110% 125%*

ASME Code,. 1949 Edition, Paragraphs U-200 and U-201, and all ASME Codes later than 1949 88% 100%*

AYI Standard 620 100%*

*Manufacturers of relief valves are allowed a plus tolerance not exceeding 10 percent of the set pressure marked on the valve.

79. Revise 633 as follows:

633. Relief devices on containers shall be constructed to dis- charge at not less than the rates shown in Appendix A or E before the pressure is in excess of 120 percent of the maximum (not in- cluding the 10 percent referred to in the asterisked note of Table 6) permitted start to discharge pressure setting of the de- vices.

0,

81.

8~.

88.

84.

Delete 634.

Renumber existing 635 as 634.

Revise 640 by changing "should" to "shall" in the last line.

Revise 64t by changing "should" to "shall" in the third line.

Revise the second sentence of 660 as follows:

The start to discharge pressure of such relief devices shall be not in excess of 500 psig.

85. Revise 710 by changing existing "may" to "is permitted to".

86. Delete 710(b).

87. Revise the second sentence of 711 by changing "may" to "is permi.tted to".

88. Revise 711(a) by changing "must" to "shall" in the first line.

89. Delete 711(e).

1262 LPG-34 AMENDMENTS TO NO. 59

90. Renumber existing 711(d) as 711(c) and change "should" to "shall".

9I. Revise 7I~ as follows:

712. Transfer operations shall be conducted by competent trained personnel. At least one qualified person shall remain at or near the transfer operation from the time connections are made until the transfer is completed, shutoff valves are closed, and lines are disconnected.

9~. Revise 71~ as follows:

714. Unloading piping or hoses shall be provided with suit- able bleeder valves or other means for relieving pressure before disconnection.

95. Delete existing 7~8, 7 ~ , 7~5 and 7~6.

J 9~. Add a new 73 as follows:

73. Tank Truck Loading and Unloading 730. The area of tank truck transfer shall be relatively level.

731. A tank truck loading and unloading area shall be of sufficient size to accommodate the vehicles without excessive movement or turning. Tank trucks or transports unloading into storage containers shall be at least 10 feet from the container and so positioned that the shutoff valves on both the truck and the container are readily accessible.

732. While trucks are loading or unloading, the wheels shall be blocked.

95. Revise 810 by changing "should" to "shall" in two places in the second 8~rtterw~.

96. Revise 811 as follows:

811. Gas fires shall normally not be extinguished until the source of the burning gas has been shut off. Remotely operated or remotely located pipeline valves are advantageously used for fire control under many circumstances.

97. Revise 8If~ by changing "should" to "shall".

98. Revise 814 by changing "may" to "is permitted to".

99. Revise 817 by changing "should" to "shall".