13VAC5-63-310: Chapter 28 Mechanical systems
Where this section sits in the code
- Title 13. Housing
- Agency 5. Department of Housing And Community Development
- Chapter 63. Virginia Uniform Statewide Building Code
- Part I. Construction
A. Change Section 2801.1 of the IBC to read:
2801.1 Scope. Mechanical appliances, equipment, and systems shall be constructed and installed in accordance with this chapter, the IMC, and the IFGC. Masonry chimneys, fireplaces, and barbecues shall comply with the IMC and Chapter 21 of this code.
Exception: This code shall not govern the construction of water heaters, boilers, and pressure vessels to the extent that they are regulated by the Virginia Boiler and Pressure Vessel Regulations (16VAC25-50). However, the building official may require the owner of a structure to submit documentation to substantiate compliance with those regulations.
B. Add Section 2801.1.1 to the IBC to read:
2801.1.1 Required heating in dwelling units. Heating facilities shall be required in every dwelling unit or portion thereof that is to be rented, leased, or let on terms, either expressed or implied, to furnish heat to the occupants thereof. The heating facilities shall be capable of maintaining the room temperature at 65°F (18°C) during the period from October 15 to May 1 during the hours between 6:30 a.m. and 10:30 p.m. of each day and not less than 60°F (16°C) during other hours when measured at a point three feet (914 mm) above the floor and three feet (914 mm) from the exterior walls. The capability of the heating system shall be based on the outside design temperature required for the locality by this code.
C. Add Section 2801.1.2 to the IBC to read:
2801.1.2 Required heating in nonresidential structures. Heating facilities shall be required in every enclosed occupied space in nonresidential structures. The heating facilities shall be capable of producing sufficient heat during the period from October 1 to May 15 to maintain a temperature of not less than 65°F (18°C) during all working hours. The required room temperature shall be measured at a point three feet (914 mm) above the floor and three feet (914 mm) from the exterior walls.
Processing, storage, and operation areas that require cooling or special temperature conditions and areas in which persons are primarily engaged in vigorous physical activities are exempt from these requirements.
D. Add Section 2801.1.3 to the IBC to read:
2801.1.3 Changes to the IMC. The following changes shall be made to the IMC:
1. Add the following definitions to Section 202 of the IMC:
Refrigerant designation. The unique identifying alphanumeric value or refrigerant number assigned to an individual refrigerant and published in ASHRAE Standard 34.
2. Change Section 401.2 of the IMC to read:
401.2 Ventilation required. Every occupied space shall be ventilated by natural means in accordance with Section 402 or by mechanical means in accordance with Section 403. Group R dwelling units shall be ventilated by mechanical means in accordance with Section 403. Ambulatory care facilities and Group I-2 occupancies shall be ventilated by mechanical means in accordance with Section 407.
3. Change Section 403.3.1.1 of the IMC to read:
403.3.1.1 Outdoor airflow rate. Ventilation systems shall be designed to have the capacity to supply the minimum outdoor airflow rate determined in accordance with this section. In each occupiable space, the ventilation system shall be designed to deliver the required rate of outdoor airflow to the breathing zone. The occupant load utilized for design of the ventilation system shall not be less than the number determined from the estimated maximum occupant load rate indicated in Table 403.3.1.1. Ventilation rates for occupancies not represented in Table 403.3.1.1 shall be those for a listed occupancy classification that is most similar in terms of occupant density, activities, and building construction or shall be determined by an approved engineering analysis. The ventilation system shall be designed to supply the required rate of ventilation air continuously during the period the building is occupied, except as otherwise stated in other provisions of the code.
With the exception of smoking lounges and other designated areas where smoking is permitted, the ventilation rates in Table 403.3.1.1 are based on the absence of smoking in occupiable spaces.
Exception: The occupant load is not required to be determined based on the estimated maximum occupant load rate indicated in Table 403.3.1.1 where approved statistical data document the accuracy of an alternate anticipated occupant density.
4. Add the following rows to Table 403.3.1.1 of the IMC to read:
OCCUPANCY CLASSIFICATION
Occupant Density #/1000 ft2 a
People Outdoor Airflow Rate in Breathing Zone,
Rp cfm/person
Area Outdoor Airflow Rate in Breathing Zone, Ra cfm/ft2a
Exhaust Airflow Rate
Cfm/ft2a
Food and beverage service
Bars or cocktail lounges designated as an area where smoking is permittedb
100
30
--
--
Cafeteria or fast food designated as an area where smoking is permittedb
100
20
--
--
Dining rooms designated as an area where smoking is permittedb
70
20
--
--
Public spaces
Lounges designated as an area where smoking is permittedb
100
30
--
--
Medical procedure roomsI
20
15
-
-
Patient roomsI
10
25
-
-
Physical therapy roomsI
20
15
-
-
i. For spaces that are located in clinic, outpatient facilities as defined in Chapter 2 of the VCC.
5. Change Section 504.9.2 of the IMC to read:
504.9.2 Duct installation. Exhaust ducts shall be supported at four-foot (1219 mm) intervals and secured in place. The insert end of the duct shall extend into the adjoining duct or fitting in the direction of airflow. Ducts shall not be joined with screws or similar fasteners that protrude into the inside of the duct.
Where dryer exhaust ducts are enclosed in wall or ceiling cavities, such cavities shall allow the installation of the duct without deformation.
6. Change Item 2 of Section 504.11 to read:
2. Dampers shall be prohibited in the exhaust duct. Penetrations of the shaft and ductwork shall be protected in accordance with Section 607.5.5, Exception 1.
7. Change Exception 1 of Section 505.3 of the IMC to read:
1. In Group R buildings, where installed in accordance with the manufacturer's installation instructions and where mechanical or natural ventilation is otherwise provided in accordance with Chapter 4, listed and labeled ductless range hoods shall not be required to discharge to the outdoors.
8. Change Item 2 in Section 505.5 to read:
2. Penetrations of the shaft and ductwork shall be protected in accordance with Section 607.5.5.
9. Change Section 505.6 of the IMC to read:
505.6 Other than Group R. In other than Group R occupancies, where electric domestic cooking appliances are utilized for domestic purposes, domestic range hoods shall be permitted for such appliances. Hoods and exhaust systems for such electric domestic cooking appliances shall be in accordance with Sections 505.2 and 505.4. In other than Group R occupancies, where fuel-fired domestic cooking appliances are utilized for domestic purposes, a Type I or Type II hood shall be provided as required for the type of appliances and processes in accordance with Section 507.1.
10. Change Section 510.6.1.1 of the IMC to read:
510.6.1.1 Shaft penetrations. Hazardous exhaust ducts that penetrate fire-resistance-rated shafts shall comply with Section 713.11 of the International Building Code.
11. Change Section 607.5.5 of the IMC to read:
607.5.5 Shaft enclosures. Shaft enclosures that are permitted to be penetrated by ducts and air transfer openings shall be protected with approved fire and smoke dampers installed in accordance with their listing.
Exceptions:
1. Fire and smoke dampers are not required where steel exhaust subducts extend at least 22 inches (559 mm) vertically in exhaust shafts, provided there is a continuous airflow upward to the outside.
2. Fire dampers are not required where penetrations are tested in accordance with ASTM E119 as part of the fire-resistance-rated assembly.
3. Fire and smoke dampers are not required where ducts are used as part of an approved smoke control system in accordance with Section 909 of the International Building Code.
4. Fire and smoke dampers are not required where the penetrations are in parking garage exhaust or supply shafts that are separated from other building shafts by not less than two-hour fire-resistance-rated construction.
5. Smoke dampers are not required where the building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 of the International Building Code.
12. Add Section 607.6.2.2 to the IMC to read:
607.6.2.2 Equipment shutdown. Where ceiling radiation dampers are listed as static dampers, the HVAC equipment shall be effectively shut down to stop the airflow prior to the damper closing using one of the following methods:
1. A duct detector installed in the return duct.
2. An area smoke detector interlocked with the HVAC equipment.
3. A listed heat sensor installed in the return duct.
13. Change Table 1101.2 to read:
EQUIPMENT
STANDARDS
Refrigeration fittings, including press-connect, flared and threaded
UL 109 and UL 207
Air-conditioning equipment and heat pump equipment
UL 1995 or UL/CSA 60335-2-40
Packaged terminal air conditioners and heat pumps
UL 484 or UL/CSA 60335-2-40
Split-system air conditioners and heat pumps
UL 1995 or UL/CSA 60335-2-40
Dehumidifiers
UL 474 or UL/CSA 60335-2-40
Air/water cooled condensers
UL 1995 or UL/CSA 60335-2-40 or UL/CSA 60335-2-89
Refrigeration equipment
UL 1995 or UL/CSA 60335-2-89
Unit coolers
UL 412 or UL/CSA 60335-2-89
Commercial refrigerators, freezers, beverage coolers, and walk-in coolers
UL 471 or UL/CSA 60335-2-89
Refrigerating units and walk-in coolers
UL 427 or UL 60335-2-89
Refrigeration condensing units
UL 1995 or UL/CSA 60335-2-89
Automatic commercial ice machines
UL 563 or UL/CSA 60335-2-89
Refrigerant-containing components and accessories
UL 207
14. Add Section 1101.2.1 to read:
1101.2.1 Group A2L, A2, A3, and B1 high probability equipment. High probability equipment using Group A2L, A2, A3, or B1 refrigerant shall comply with UL 484, UL/CSA 60335-2-40, or UL/CSA 60335-2-89.
15. Change Sections 1101.7 and 1102.2.1 to read:
1101.7 Changing refrigerant. Changes of refrigerant in an existing system to a refrigerant with a different refrigerant designation shall only be allowed where in accordance with the following:
1. The owner or the owner's authorized agent shall be notified prior to making a change of refrigerant, and the change of refrigerant shall not be made where the owner objects to the change.
2. The change in refrigerant shall be in accordance with one of the following.
2.1 Written instructions of the original equipment manufacturer.
2.2 An evaluation of the system by a registered design professional or by an approved agency that validates safety and suitability of the replacement refrigerant.
2.3 Approved by the code official.
3. Where the replacement refrigerant is classified into the same safety group, requirements that were applicable to the existing system shall continue to apply.
4. Where the replacement refrigerant is classified into a different safety group, the system shall comply with the requirements of this standard for a new installation, and the change of refrigerant shall require code official approval.
1102.2.1 Mixing. Refrigerants with different refrigerant designations shall only be mixed in a system in accordance with both of the following:
1. The addition of a second refrigerant is allowed by the equipment manufacturer and is in accordance with the manufacturer's written instructions.
2. The resulting mixture does not change the refrigerant safety group.
16. Change Table 1103.1 of the IMC to read (portions of table not shown remain):
TABLE 1103.1 REFRIGERANT CLASSIFICATION, AMOUNT AND OEL
Chemical Refrigerant
Formula
Chemical Name of Blend
Refrigerant Safety Group Classification
AMOUNT OF REFRIGERANT PER OCCUPIED SPACE
RCL
LFL
OELd
lb/MCf
ppm
g/m3
lb/MCf
ppm
g/m3
ppm
R-11c
CCl3F
trichlorofluoromethane
A1
0.39
1,100
6.1
1,000
R-12c
CCl2F2
dichlorodifluoromethane
A1
5.6
18,000
90
1,000
R-13c
CClF3
chlorotrifluoromethane
A1
—
—
—
1,000
R-13B1c
CBrF3
bromotrifluoromethane
A1
—
—
—
1,000
R-13I1
CF3I
trifluoroiodomethane
A1
1.0
2,000
16
500
R-31
CH2ClF
chlorofluoromethane
-
-
-
-
-
R-32
CH2F2
difluoromethane (methylene fluoride)
A2L
4.8
36,000
77
19.1
144,000
306
1,000
R-41
CH3F
fluoromethane (methyl fluoride)
-
-
-
-
-
R-50
CH4
methane
A3
—
—
—
50,000
1,000
R-113c
CCl2FCClF2
1,1,2-trichloro-1,2,2-trifluoroethane
A1
1.2
2,600
20
1,000
R-114c
CClF2CClF2
1,2-dichloro-1,1,2,2-tetrafluoroethane
A1
8.7
20,000
140
1,000
R-141b
CH3CCl2F
1,1-dichloro-1-fluoroethane
—
0.78
2,600
12
17.8
60,000
287
500
R-142b
CH3CClF2
1-chloro-1,1-difluoroethane
A2
5.1
20,000
82
20.4
80,000
329
1,000
R-143a
CH3CF3
1,1,1-trifluoroethane
A2L
4.4
21,000
70
17.5
82,000
282
1,000
R-152a
CH3CHF2
1,1-difluoroethane
A2
2.0
12,000
32
8.1
48,000
130
1,000
R-170
CH3CH3
ethane
A3
0.54
7,000
8.6
2.4
31,000
38
1,000
R-E170
CH3OCH3
Methoxymethane (dimethyl ether)
A3
1.0
8,500
16
4.0
34,000
64
1,000
R-290
CH3CH2CH3
propane
A3
0.59
5,300
9.5
2.4
21,000
38
1,000
R-C318
(CF2)4
octafluorocyclobutane
A1
41
80,000
650
1,000
R-400Ac
zeotrope
R-12/114 (50.0/50.0)
A1
10
28,000
160
1,000
R-400Bc
zeotrope
R-12/114 (60.0/40.0)
A1
11
30,000
170
1,000
R-403B
zeotrope
R-290/22/218 (5.0/56.0/39.0)
A1
18
68,000
290
1,000
R-406A
zeotrope
R-22/600a/142b (55.0/4.0/41.0)
A2
4.7
21,000
75
18.8
82,000
301.9
1,000
R407I
zeotrope
R-32/125/134a(19.5/8.5/72.0)
A1
16
71,100
250
1,000
R-408A
zeotrope
R-125/143a/22 (7.0/46.0/47.0)
A1
21
94,000
330
1,000
R-411A
zeotrope
R-127/22/152a (1.5/87.5/11.0)
A2
2.9
14,000
46
11.6
55,000
185.6
970
R-411B
zeotrope
R-1270/22/152a (3.0/94.0/3.0)
A2
2.8
13,000
45
14.8
70,000
238.3
940
R-412A
zeotrope
R-22/218/142b (70.0/5.0/25.0)
A2
5.1
22,000
82
20.5
87,000
328.6
1,000
R-413A
zeotrope
R-218/134a/600a (9.0/88.0/3.0)
A2
5.8
22,000
93
23.4
88,000
374.9
1,000
R-414B
zeotrope
R-22/124/600a/142b (50.0/39.0/1.5/9.5)
A1
6.0
23,000
96
1,000
R-417A
zeotrope
R-125/134a/600 (46.6/50.0/3.4)
A1
3.5
13,000
55
1,000
R-417B
zeotrope
R-125/134a/600 (79.0/18.3/2.7)
A1
4.3
15,000
69
1,000
R-418A
zeotrope
R-290/22/152a (1.5/96.0/2.5)
A2
4.8
22,000
77
19.2
89,000
308.4
1,000
R-419A
zeotrope
R-125/134a/E170 (77.0/19.0/4.0)
A2
4.2
15,000
67
16.7
60,000
268.6
1,000
R-419B
zeotrope
R-125/134a/E170 (48.5/48.0/3.5)
A2
4.6
17,000
74
18.5
69,000
297.3
1,000
R-420A
zeotrope
R-134a/142b (88.0/12.0)
A1
12
44,000
180
1,000
R-423A
zeotrope
R-134a/227ea (52.5/47.5)
A1
19
59,000
300
1,000
R-424A
zeotrope
R-125/134a/600a/600/601a (50.5/47.0/0.9/1.0/0.6)
A1
6.2
23,000
100
990
R-428A
zeotrope
R-125/143a/290/600a (77.5/20.0/0.6/1.9)
A1
23
84,000
370
1,000
R-429A
zeotrope
R-E170/152a/600a (60.0/10.0/30.0)
A3
0.81
6,300
13
3.2
25,000
83.8
1,000
R-430A
zeotrope
R-152a/600a (76.0/24.0)
A3
1.3
8,000
21
5.2
32,000
44.0
1,000
R-431A
zeotrope
R-290/152a (71.0/29.0)
A3
0.68
5,500
11
2.7
22,000
38.6
1,000
R-432A
zeotrope
R-1270/E170 (80.0/20.0)
A3
0.13
1,200
2.1
2.4
22,000
39.2
550
R-433A
zeotrope
R-1270/290 (30.0/70.0)
A3
0.34
3,100
5.5
2.4
20,000
32.4
760
R-433B
zeotrope
R-1270/290 (5.0-95.0)
A3
0.39
3,500
6.3
2.0
18,000
32.1
950
R-433C
zeotrope
R-1270/290 (25.0-75.0)
A3
0.41
3,700
6.5
2.0
18,000
83.8
790
R-435A
zeotrope
R-E170/152a (80.0/20.0)
A3
1.1
8,500
17
4.3
34,000
68.2
1,000
R-436A
zeotrope
R-290/600a (56.0/44.0)
A3
0.50
4,000
8.1
2.0
16,000
32.2
1,000
R-436B
zeotrope
R-290/600a (52.0/48.0)
A3
0.51
4,000
8.2
2.0
16,000
32.7
1,000
R-437A
zeotrope
R-125/134a/600/601 (19.5/78.5/1.4/0.6)
A1
5.1
19,000
82
990
R-439A
zeotrope
R-32/125/600a (50.0/47.0/3.0)
A2
4.7
26,000
76
18.9
104,000
303.3
1,000
R-440A
zeotrope
R-290/134a/152a (0.6/1.6/97.8)
A2
1.9
12,000
31
7.8
46,000
124.7
1,000
R-441A
zeotrope
R-170/290/600a/600 (3.1/54.8/6.0/36.1)
A3
0.39
3,200
6.3
2.0
16,000
31.7
1,000
R-443A
zeotrope
R-1270/290/600a (55.0/40.0/5.0)
A3
0.19
1,700
3.1
2.2
20,000
35.6
640
R-444A
zeotrope
R-32/152a/1234ze(E) (12.0/5.0/83.0)
A2L
5.1
21,000
81
19.9
82,000
324.8
850
R-444B
zeotrope
R-32/152a/1234ze(E) (41.5/10.0/48.5)
A2L
4.3
23,000
69
17.3
93,000
277.3
930
R-445A
zeotrope
R-744/134a/1234ze(E) (6.0/9.0/85.0)
A2L
4.2
16,000
67
21.7
63,000
347.4
930
R-446A
zeotrope
R-32/1234ze(E)/600 (68.0/29.0/3.0)
A2L
2.5
16,000
39
13.5
62,000
217.4
960
R-447A
zeotrope
R-32/125/1234ze(E) (68.0/3.5/28.5)
A2L
2.6
16,000
42
18.9
65,000
303.5
960
R-447B
zeotrope
R-32/125/1234ze(E) (68.0/8.0/24.0)
A2L
23
16,000
42
20.6
121,000
312.7
970
R-448A
zeotrope
R-32/125/1234yf/134a/1234ze(E) (26.0/26.0/20.0/21.0/7.0)
A1
24
110,000
390
860
R-449A
zeotrope
R-32/125/1234yf/134a (24.3/24.7/25.3/25.7)
A1
23
100,000
370
840
R-451A
zeotrope
R-1234yf/134a (89.8/10.2)
A2L
5.3
18,000
81
20.3
70,000
326.6
530
R-451B
zeotrope
R-1234yf/134a (88.8/11.2)
A2L
5.3
18,000
81
20.3
70,000
326.6
530
R-452A
zeotrope
R-32/125/1234yf (11.0/59.0/30.0)
A1
27
100,000
440
790
R-452B
zeotrope
R-32/125/1234yf (67.0/7.0/26.0)
A2L
4.8
30,000
77
19.3
119,000
310.5
870
R-452C
zeotrope
R-32/125/1234yf (12.5/61.0/26.5)
A1
27
100,000
430
810
R-454A
zeotrope
R-32/1234yf (35.0/65.0)
A2L
3.2
16,000
52
18.3
63,000
293.9
690
R-454B
zeotrope
R-32/1234yf (68.9/31.1)
A2L
3.1
19,000
49
22.0
77,000
352.6
850
R-454C
zeotrope
R-32/1234yf (21.5/78.5)
A2L
4.4
19,000
71
18.0
62,000
289.5
620
R-455A
zeotrope
R-744/32/1234yf (3.0/21.5/75.5)
A2L
4.9
22,000
79
26.9
118,000
432.1
650
R-457A
zeotrope
R-32/1234yf/152a (18.0/70.0/12.0)
A2L
3.4
15,000
54
13.5
60,000
216.3
650
R-457B
zeotrope
R-32/1234yf/152a (35.0/55.0/10.0)
A2L
3.7
19,000
59
14.9
76,000
239
730
R-459A
zeotrope
R-32/1234yf/1234ze(E) (68.0/26.0/6.0)
A2L
4.3
27,000
69
17.4
107,000
278.7
870
R-459B
zeotrope
R-32/1234yf/1234ze(E) (21.0/69.0/10.0)
A2L
30
25,000
92
23.3
99,000
373.5
640
R-460A
zeotrope
R-32/125/134a/1234ze(E) (12.0/52.0/14.0/22.0)
A1
24
92,000
380
950
R-460C
zeotrope
R-32/125/134a/1234ze(E) (2.5/52.5/46.0/49.0)
A1
20
73,000
310
900
R-462A
zeotrope
R-32/125/143a/134a/600 (9.0/42.0/2.0/44.0/3.0)
A2
3.9
16,000
62
16.6
105,000
265.8
1,000
R-464A
zeotrope
R-32/125/1234ze(E)/227ea (27.0/27.0/40.0/6.0)
A1
27
120,000
430
930
R-465A
zeotrope
R-32/290/1234yf (21.0/7.9/71.1)
A2
2.5
12,000
40
10.0
98,000
160.9
660
R-466A
zeotrope
R-32/125/13I1 (49.0/11.5/39.5)
A1
6.2
30,000
99
860
R-467A
zeotrope
R-32/125/134a/600a (22.0/5.0/72.4/0.6)
A2L
6.7
31,000
110
1,000
R-468A
zeotrope
R-1132a/32/1234yf (3.5/21.5/75.0)
A2L
4.1
16,00
66
610
R-469A
zeotrope
R-744/32/125 (35.0/32.5/32.5)
A1
8
53,000
1,600
R-470A
zeotrope
R-744/32/125/134a/1234ze(E)/227ea
(10.0/17.0/19.0/7.0/44.0/3.0)
A1
17
77,00
270
1,100
R-470B
zeotrope
R-744/32/125/134a/1234ze(E)/227ea
(10.0/11.5/11.5/3.0/57.0/7.0)
A1
16
72,000
270
1,100
R-471A
zeotrope
R-1234ze(E )/227ea/1336mzz(E ) (78.7/4.3/17.0)
A1
9.7
31,000
160
710
R-472A
zeotrope
R-744/32/134a (69.0/12.0/19.0)
A1
4.5
35,000
72
2,700
R-500d
azeotrope
R-12/152a (73.8/26.2)
A1
7.4
29,000
120
1,000
R-501
azeotrope
R-22/12 (75.0/25.0)
A1
13
54,000
210
1,000
R-502d
azeotrope
R-22/115 (48.8/51.2)
A1
21
73,000
330
1,000
R-503d
azeotrope
R-23/13 (40.1/59.9)
—
—
—
—
1,000
R-504e
azeotrope
R-32/115 (48.2/51.8)
—
28
140,000
450
1,000
R-507A
azeotrope
R-125/143a (50.0/50.0)
A1
32
130,000
510
1,000
R-509A
azeotrope
R-22/218 (44.0/56.0)
A1
24
75,000
380
1,000
R-510A
azeotrope
R-E170/600a (88.0/12.0)
A3
0.87
7,300
14
3.5
29,000
56.1
1,000
R-511A
azeotrope
R-290/E170 (95.0/5.0)
A3
0.59
5,300
9.5
2.4
21,000
38.0
1,000
R-512A
azeotrope
R-134a/152a (5.0/95.0)
A2
1.9
11,000
31
7.7
45,000
123.9
1,000
R-515A
azeotrope
R-1234ze(E)/227ea (88.0/12.0)
A1
19
63,000
300
810
R-515B
azeotrope
R-1234ze(E)/227ea (91.1/8.9)
A1
18
61,000
290
810
R-516A
azeotrope
R-1234yf/134a/152a (77.5/8.5/14.0)
A2
3.2
13,000
52
13.1
50,000
210.1
590
R-600
CH3CH2CH2CH3
butane
A3
0.15
1,000
2.4
3.0
20,000
48
1,000
R-600a
CH(CH3)2CH3
2-methylpropane (isobutane)
A3
0.59
4,000
9.6
2.4
16,000
38
1,000
R-601
CH3CH2CH2 CH2CH3
pentane
A3
0.18
1,000
2.9
2.2
12,000
35
600
R-601a
(CH3)2CHCH2CH3
2-methylbutane (isopentane)
A3
0.18
1,000
2.9
2.4
13,000
38
600
R-717
NH3
ammonia
B2L
0.014
320
0.22
7.2
167,000
116
25
R-1130(E)
CHCl=CHCl
trans-1,2-dichloroethene
B2
0.25
1,000
4
16
65,000
258
200
R-1132a
CF2=CH2
1,1-difluoroethylene
A2
2.0
13,000
33
8.1
50,000
131
500
R-1150
CH2=CH2
ethene (ethylene)
A3
—
—
—
2.2
31,000
36
200
R-1224yd(Z)
CF3CF=CHCl
(Z)-1-chloro-2,3,3,3-tetrafluoroethylene
A1
23
60,000
370
1,000
R-1234yf
CF3CF=CH2
2,3,3,3-tetrafluoro-1-propene
A2L
4.7
16,000
75
18.0
62,000
289
500
R-1234ze(E)
CF3CH=CHF
trans-1,3,3,3-tetrafluoro-1-propene
A2L
4.7
16,000
76
18.8
65,000
303
800
R-1270
CH3CH=CH2
Propene (propylene)
A3
0.1
1,000
1.7
500
R-1336mzz(E)
CF3CHCHCF3
trans-1,1,1,4,4,4-hexaflouro-2-butene
A1
3.0
7,200
48
400
R-1336mzz(Z)
CF3CHCHCF3
cis-1,1,1,4,4,4-hexaflouro-2-butene
A1
5.2
13,000
84
500
a. Degrees of hazard are for health, fire, and reactivity, respectively, in accordance with NFPA 704.
b. Reduction to 1-0-0 is allowed if analysis satisfactory to the code official shows that the maximum concentration for a rupture or full loss of refrigerant charge would not exceed the IDLH, considering both the refrigerant quantity and room volume.
c. Class 1 ozone depleting substance; prohibited for new installations.
d. Occupational Exposure Limit based on the OSHA PEL, ACGIH TLV-TWA, the TERA WEEL or consistent value on a time-weighed average (TWA) basis (unless noted C for ceiling) for an 8 hr/d and 40 hr/wk.
17. Change Section 1104.3.1 of the IMC to read:
1104.3.1 Air conditioning for human comfort. High probability systems used for human comfort shall use Group A1 or A2L refrigerant.
Exceptions:
1. Listed equipment for residential occupancies containing a maximum of 6.6 pounds (3 kg) of refrigerant.
2. Listed equipment for commercial occupancies containing a maximum of 22 pounds (10 kg) of refrigerant.
3. Industrial occupancies.
18. Change Section 1104.3.2 of the IMC to read:
1104.3.2 Group A3 and B3 refrigerants. Group A3 and B3 refrigerants shall not be used except where approved.
Exceptions: This section does not apply to:
1. Laboratories where the floor area per occupant is not less than 100 square feet (9.3 m2).
2. Listed self-contained systems having a maximum of 0.331 pounds (150 g) of Group A3 refrigerant.
3. Self-contained systems listed per UL 60335-2-89 having a maximum of 1.1 pounds (500g) of Group A3 refrigerant.
4. Industrial occupancies.
5. Equipment listed for and used in residential occupancies containing a maximum of 6.6 pounds (3 kg) of Group A2 or B2 refrigerant.
6. Equipment listed for and used in commercial occupancies containing a maximum of 22 pounds (10 kg) of Group A2 or B2 refrigerant.
19. Delete Table 1104.3.2 of the IMC.
20. Delete the exception to Section 1106.3 of the IMC and change Section 1106.3 of the IMC to read:
1106.3 Class 2 and Class 3 refrigerants. Where refrigerants of Groups A2, A3, B2, and B3 are used, the machinery room shall conform to the Class I, Division 2, hazardous location classification requirements of NFPA 70.
21. Delete the exception to Section 1106.4 and change Section 1106.4 of the IMC to read:
1106.4 Group A2L and B2L refrigerant. Machinery rooms for Group A2L and Group B2L refrigerant shall comply with Sections 1106.4.1 through 1106.4.3.
22. Change Section 1106.4.1 to the IMC to read:
1106.4.1 Elevated temperature. Open flame-producing devices or continuously operating hot surfaces over 1290 °F (700 °C) shall not be permanently installed in the room
23. Change Section 1106.4.2 of the IMC to read:
1106.4.2 Refrigerant detector. In addition to the requirements of Section 1105.3, refrigerant detectors shall signal an alarm and activate the ventilation system in accordance with the response time specified in Table 1106.4.2.
24. Replace Table 1106.4.2 of the IMC with the following:
Table 1106.4.2 GROUP A2L and B2L DETECTOR ACTIVATION
Activation Level
Maximum Response Time (seconds)
ASHRAE 15 Ventilation Level
Alarm Reset
Alarm Type
Less than or equal to the OEL in Table 1103.1
300
1
Automatic
Trouble
Less than or equal to the refrigerant concentration level in Table 1103.1
15
2
Manual
Emergency
25. Change Section 1106.4.3 of the IMC to read:
1106.4.3 Mechanical Ventilation. The machinery room shall have a mechanical ventilation system complying with ASHRAE 15.
26. Add the following standards to the list of referenced standards in Chapter 15 of the IMC:
Standard Reference Number
Title
UL 484-2019
Standard for Room Air Conditioners
UL/CSA 60335-2-40-2019
Household and Similar Electrical Appliances-Safety-Part 2-40: Particular Requirements for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers
UL/CSA 60335-2-89-2021
Household and Similar Electrical Appliances—Safety—Part 2-89: Particular Requirements for Commercial Refrigerating Appliances and Ice-Makers with an Incorporated or Remote Refrigerant Unit or Motor-Compressor
27. Delete the following standards from the list of referenced standards in Chapter 15 of the IMC:
Standard Reference Number
Title
UL 484-2014
Standard for Room Air Conditioners
UL/CSA 60335-2-40-2017
Household and Similar Electrical Appliances-Safety-Part 2-40: Particular Requirements for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers
UL/CSA 60335-2-89-2017
Household and Similar Electrical Appliances—Safety—Part 2-89: Particular Requirements for Commercial Refrigerating Appliances and Ice-Makers with an Incorporated or Remote Refrigerant Unit or Motor-Compressor
UL 109—97
Tube Fittings for Flammable and Combustible Fluids, Refrigeration Service and Marine Use
UL 207—2009
Refrigerant-containing Components and Accessories, Nonelectrical - with revisions through June 2014
E. Add Section 2801.1.4 to the IBC to read:
2801.1.4 Changes to the IFGC. The following changes shall be made to the IFGC:
1. Change Section 301.1 of the IFGC to read:
301.1 Scope. This code shall apply to the installation of fuel gas piping systems, fuel gas utilization equipment, and related accessories as follows:
1. Coverage of piping systems shall extend from the point of delivery to the connections with gas utilization equipment. (See "point of delivery.")
2. Systems with an operating pressure of 125 psig (862 kPa gauge) or less.
Piping systems for gas-air mixtures within the flammable range with an operating pressure of 10 psig (69 kPa gauge) or less.
LP-Gas piping systems with an operating pressure of 20 psig (140 kPa gauge) or less.
3. Piping systems requirements shall include design, materials, components, fabrication, assembly, installation, testing, and inspection.
4. Requirements for gas utilization equipment and related accessories shall include installation, combustion, and ventilation air and venting.
This code shall not apply to the following:
1. Portable LP-Gas equipment of all types that are not connected to a fixed fuel piping system.
2. Installation of farm equipment such as brooders, dehydrators, dryers, and irrigation equipment.
3. Raw material (feedstock) applications except for piping to special atmosphere generators.
4. Oxygen-fuel gas cutting and welding systems.
5. Industrial gas applications using gases such as acetylene and acetylenic compounds, hydrogen, ammonia, carbon monoxide, oxygen, and nitrogen.
6. Petroleum refineries, pipeline compressor or pumping stations, loading terminals, compounding plants, refinery tank farms, and natural gas processing plants.
7. Integrated chemical plants or portions of such plants where flammable or combustible liquids or gases are produced by chemical reactions or used in chemical reactions.
8. LP-Gas installations at utility gas plants.
9. Liquefied natural gas (LNG) installations.
10. Fuel gas piping in power and atomic energy plants.
11. Proprietary items of equipment, apparatus, or instruments such as gas generating sets, compressors, and calorimeters.
12. LP-Gas equipment for vaporization, gas mixing, and gas manufacturing.
13. Temporary LP-Gas piping for buildings under construction or renovation that is not to become part of the permanent piping system.
14. Installation of LP-Gas systems for railroad switch heating.
15. Installation of LP-Gas and compressed natural gas (CNG) systems on vehicles.
16. Except as provided in Section 401.1.1, gas piping, meters, gas pressure regulators, and other appurtenances used by the serving gas supplier in the distribution of gas, other than undiluted LP-Gas.
17. Building design and construction, except as specified herein.
2. Change Section 301.3 of the IFGC to read:
301.3 Listed and labeled. Appliances regulated by this code shall be listed and labeled for the application in which they are used unless otherwise approved in accordance with Section 112. The approval of unlisted appliances in accordance with Section 112 shall be based on approved engineering evaluation.
3. Add Section 404.11.5 to the IFGC to read:
404.11.5 Coating application. Joints in gas piping systems shall not be coated prior to testing and approval.
4. Change Item 6 of Section 410.2 of the IFGC to read (Items 1 through 5 and Item 7 remain):
6. Means shall be provided downstream of the MP regulator for the connection of a pressure measuring instrument and shall be positioned to allow connection of a pressure measuring instrument. Such means shall be permitted to be a dedicated test port on a regulator, gas control, or manifold or a plugged tee fitting or plugged manifold port.
5. Change Section 614.9.2 of the IFGC to read:
614.9.2 Duct installation. Exhaust ducts shall be supported at 4-foot (1219 mm) intervals and secured in place. The insert end of the duct shall extend into the adjoining duct or fitting in the direction of airflow. Ducts shall not be joined with screws or similar fasteners that protrude into the inside of the duct.
Where dryer exhaust ducts are enclosed in wall or ceiling cavities, such cavities shall allow the installation of the duct without deformation.
6. Add the following standards to the list of referenced standards in Chapter 8 of the IFGC:
Standard Reference Number
Title
ANSI LC1/CSA 6.26-18
Fuel Gas Piping Systems Using Corrugated Stainless Steel Tubing (CSST)
7. Delete the following standards from the list of referenced standards in Chapter 8 of the IFGC:
Standard Reference Number
Title
ANSI LC1/CSA 6.26-16
Fuel Gas Piping Systems Using Corrugated Stainless Steel Tubing (CSST)
Collected 2026-09-14T04:51:39Z. Source file · JSON