CBC · California Building Code
Laboratory ventilation, means of egress and percentage-of-MAQ limits
For homeowners: labs must have continuous exhaust sized to 1 cfm per sq. ft. or 6 air changes per hour, rooms with hazardous materials over 500 sq. ft. need two exits with doors swinging outward and panic hardware, and chemical storage limits are set by Table 453.7.2.1 in the CBC; consult the code table for exact percentages.
Last reviewed: July 5, 2026
What the code requires — 2-4 sentences
Laboratory suites must have continuously operating mechanical exhaust sized to provide at least 1 cubic foot per minute per square foot of floor area or 6 air changes per hour, whichever is greater (CBC § 453.4.7.5) . Rooms in laboratory suites that contain hazardous materials and are 500 square feet or larger must have access to at least two exits; exit and exit‑access doors serving hazardous areas must swing in the direction of exit travel and may only be secured with panic or fire‑exit hardware (CBC § 453.6.1–.3) . The allowable percentage of the maximum allowable quantity (MAQ) of hazardous materials that may be stored per laboratory suite on each story is set by Table 453.7.2.1 (CBC § 453.7.2 and Table 453.7.2.1) .
Requirements in detail
Ventilation (design and operation)
- Minimum continuous exhaust: 1 cubic foot per minute per square foot of floor area OR 6 air changes per hour, whichever is greater (CBC § 453.4.7.5) .
- Lab exhaust must not be recirculated and must be ducted independently to outdoors or to an approved rooftop outlet (CBC § 453.4.7.4.1–.4.2) .
- Fire/smoke/fire‑smoke dampers are not permitted in mechanical exhaust ducts used to maintain a safe laboratory environment; where exhaust ducts penetrate suite boundaries they must be located within assemblies with the same fire resistance as the barrier or be enclosed in a rated shaft (CBC § 453.4.7.2 and § 453.4.7.4.3) .
- Mechanical systems must be designed and balanced so that door opening forces comply with § 1010.1.3 and Chapter 11B during normal and emergency conditions (including fan failure, damper closure or emergency power changes) (CBC § 453.4.7.7) .
Means of egress (doors, exits, thresholds)
- Two exits or exit‑access doorways are required for every room of a laboratory suite that contains hazardous materials with floor area ≥ 500 sq ft, per the exit access rules in § 1006.2 (CBC § 453.6.1) .
- Exit and exit‑access doors serving hazardous areas must swing in the direction of exit travel, regardless of occupant load (CBC § 453.6.2) .
- Exit/exit‑access doors from hazardous areas must not be provided with a latch or lock unless it is panic hardware or fire exit hardware (CBC § 453.6.3) .
- For buildings four stories or more, at least one exit must be provided to serve each side of required 2‑hour fire barriers, per Chapter 10 requirements (CBC § 453.6.4) .
Hazardous materials limits (percentage of MAQ)
- The permitted percentage of the MAQ of hazardous materials per laboratory suite, per story, is set in Table 453.7.2.1; design and storage must be compared to the MAQ values and the table’s percentage limits (CBC § 453.7.2 and Table 453.7.2.1) .
- Note: the uploaded CBC preview shows the table header and reference to Table 453.7.2.1 but the numeric percentage entries for each story level are not available in the retrieved preview; consult the full Table 453.7.2.1 in the published CBC for the actual percentages before final design or storage calculations (CBC § 453.7.2 and Table 453.7.2.1) .
Quick reference table (decision‑relevant values)
| Decision item | Value / threshold | Code Reference |
|---|---|---|
| Minimum continuous exhaust ventilation | 1 cfm per sq ft OR 6 ACH, whichever is greater | § 453.4.7.5 |
| Exhaust recirculation | Not permitted; exhaust must be independently ducted outdoors | § 453.4.7.4.1–.4.2 |
| Fire/smoke dampers in lab exhaust | Not permitted in exhaust ducts for safe lab environment | § 453.4.7.2 |
| Multi‑exit threshold (room with hazardous materials) | Room ≥ 500 sq ft requires access to ≥ 2 exits | § 453.6.1 |
| Exit door swing | Must swing in direction of exit travel | § 453.6.2 |
| Latches/locks on exit doors serving hazardous areas | Only panic hardware or fire‑exit hardware allowed | § 453.6.3 |
| Percent of MAQ allowed per story | See Table 453.7.2.1 (numeric percentages in the published table) | § 453.7.2 and Table 453.7.2.1 |
Exceptions & special cases
- Performance‑based design alternatives to the ventilation minimums may be approved by the Fire Code Official under the California Fire Code Section 5001.3; where used, document the approved alternative (CBC § 453.4.7.5 Exception) .
- Separate laboratory suites’ exhaust ducts may be connected to a common duct within a fire‑rated vertical shaft provided a sub‑duct extends vertically upward at least 22 inches (CBC § 453.4.7.4.2 Exception) .
- When an exhaust duct penetrates the laboratory suite boundary it must be located within a horizontal or vertical assembly having a fire resistance rating equal to the fire barrier, or be enclosed in a rated shaft per § 713 (CBC § 453.4.7.2 and § 453.4.7.4.3) .
- If a hazardous material has multiple hazards, those multiple hazard characteristics must be addressed per the applicable provisions of the CBC and the California Fire Code (CBC § 453.7.1) .
Common mistakes
- Undersizing exhaust by using only ACH or only cfm/sf without checking both — you must meet the larger of the two criteria in § 453.4.7.5 .
- Recirculating laboratory exhaust into the building or tying it into general HVAC return — lab exhaust must be independently ducted to outdoors (CBC § 453.4.7.4.1–.4.2) .
- Installing fire/smoke dampers inside lab exhaust ducts intended to protect occupants — the code prohibits dampers in these exhaust ducts because they can impede continuous removal of contaminants (CBC § 453.4.7.2) .
- Providing a single exit for rooms ≥ 500 sq ft that store or use hazardous materials (CBC § 453.6.1) .
- Using keyed, latched doors that do not have panic or fire‑exit hardware for exit doors serving hazardous areas (CBC § 453.6.3) .
- Assuming percentage‑of‑MAQ allowances without consulting Table 453.7.2.1 — the table controls per‑story limits and must be checked against actual MAQs (CBC § 453.7.2 and Table 453.7.2.1) .
Worked example — concrete scenario
Scenario:
- Single laboratory room, floor area = 1,200 sq ft, ceiling height = 10 ft; the room stores and uses hazardous materials.
Step 1 — Ventilation sizing:
- By area: 1 cfm/sq ft → 1,200 cfm.
- By ACH: 6 ACH → required cfm = (6 ACH × room volume) / 60 = (6 × (1,200 sq ft × 10 ft)) / 60 = (6 × 12,000) / 60 = 1,200 cfm.
- Result: Both criteria equal 1,200 cfm; provide continuous exhaust at 1,200 cfm (CBC § 453.4.7.5) .
Step 2 — Means of egress:
- Room area = 1,200 sq ft (> 500 sq ft) and contains hazardous materials → must have access to not less than two separate exits or exit‑access doorways in accordance with § 1006.2 (CBC § 453.6.1) .
- Ensure exit doors serving the laboratory swing out in the direction of exit travel and are equipped with panic or fire‑exit hardware if they are latched (CBC § 453.6.2–.3) .
Step 3 — Hazardous material quantity check:
- Determine MAQ for each hazardous material from the hazardous materials tables and calculate the suite total as a fraction of MAQ.
- Compare that fraction to the percentage allowed by Table 453.7.2.1 for the story where the suite is located.
- Note: The numeric percentage entries from Table 453.7.2.1 were not available in the retrieved preview; consult the full CBC Table 453.7.2.1 to know the allowable percentage for your story before final approval (CBC § 453.7.2 and Table 453.7.2.1) .
Related provisions (CBC sections)
- § 453.4.7.1 — Compatibility and duct conveyance rules for lab exhaust
- § 453.4.7.2 — Prohibition of fire/smoke dampers in lab exhaust ducts and duct penetration/fire‑rating requirements
- § 453.4.7.4 — Laboratory suite exhaust air (no recirculation, independent ducting, shaft exceptions)
- § 453.4.7.7 — Ventilation system balancing and door opening force requirements (references § 1010.1.3 and Chapter 11B)
- § 1006.2 — Exit access doorway requirements (referenced by § 453.6.1)
- § 1010.1.3 — Door opening force requirements (referenced by § 453.4.7.7)
- § 453.7.1 — Multiple hazards handling and technical report authority (applies when materials have multiple hazard classifications)
- § 453.7.2 and Table 453.7.2.1 — Percentage of MAQ per laboratory suite by story (consult table in the CBC)
Code references
Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:
California Building Code High relevance — show source text
4|1|086|216|130|3|602| |4:00|2|000|408|280|6|805|1|093|226|820|3|780| |4:10|2|012|427|670|7|128|1|100|237|590|3|960| |4:20|2|025|447|180|7|453|1|107|248|430|4|140| |4:30|2|038|466|810|7|780|1|114|259|340|4|322| |4:40|2|050|486|560|8|110|1|121|270|310|4|505| |4:50|2|062|506|450|8|441|1|128|281|360|4|689| |5:00|2|075|526|450|8|774|1|135|292|470|4|874| |5:10|2|088|546|580|9|110|1|142|303|660|5|061| |5:20|2|100|566|840|9|447|1|149|315|910|5|248| |5:30|2|112|587|220|9|787|1|156|326|240|5|437| |5:40|2|125|607|730|10|129|1|163|337|630|5|627| |5:50|2|138|628|360|10|473|1|170|349|930|5|818| |6:00|2|150|649|120|10|819|1|177|360|620|6|010| |6:10|2|162|670|000|11|167|1|184|372|230|6|204| |6:20|2|175|691|010|11|517|1|191|383|900|6|398| |6:30|2|188|712|140|11|869|1|198|395|640|6|594| |6:40|2|200|733|400
California Building Code High relevance — show source text
: min.|°Fahr.|°Fahr.|°Fahr.
min.|°Fahr.
min.|°Fahr.
hr.|°Fahr.
hr.|°Cent.|°Cent.|°Cent.
min.|°Cent.
min.|°Cent.
hr.|°Cent.**
hr.| |3:00|1|925|294|610|4|910|1|052|163|670|2|728| |3:10|1|938|313|250|5|221|1|059|174|030|2|900| |3:20|1|950|332|000|5|533|1|066|184|450|3|074| |3:30|1|962|350|890|5|848|1|072|194|940|3|249| |3:40|1|975|369|890|6|165|1|079|205|500|3|425| |3:50|1|988|389|030|6|484|1|086|216|130|3|602| |4:00|2|000|408|280|6|805|1|093|226|820|3|780| |4:10|2|012|427|670|7|128|1|100|237|590|3|960| |4:20|2|025|447|180|7|453|1|107|248|430|4|140| |4:30|2|038|466|810|7|780|1|114|259|340|4|322| |4:40|2|050|486|560|8|110|1|121|270|310|4|505| |4:50|2|062|506|450|8|441|1|128|281|360|4|689| |5:00|2|075|526|450|8|774|1|135|292|470|4|874| |5:10|2|088|546|580|9|110|1|142|303|660|5|061| |CBC § 1.859 High relevance — show source text
78|–|1.859|0.463| |35.31|–|2.247|0.559| |38.84|–|2.667|0.663| |42.37|–|3.121|0.775| |45.90|–|3.607|0.895| |49.43|–|4.125|1.022| |52.97|–|–|1.157| |56.50|–|–|1.299| |60.03|–|–|1.449| |63.56|–|–|1.607| |67.09|–|–|1.772| |70.62|–|–|1.944| |81.21|–|–|2.503| |91.81|–|–|3.127| |102.40|–|–|3.813|
For SI units: 1 standard cubic foot per minute = 28.32 SLPM, 1 inch = 25 mm, 1 foot = 304.8 mm, 1 pound-force per square inch = 6.8947 kPa
Notes: 1 Based on pressure of 14.7 psig (101 kPa) at 68°F (20°C). 2 Based on pressure of 55 psig (379 kPa) at 68°F (20 °C).
2025 CALIFORNIA PLUMBING CODE 291
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS
TABLE 1323.1.4(5) PRESSURE LOSS FOR VACUUM (continued)
FLOW
RATE
(SCFM)1VACUUM LOSS (inch of mercury)
PER 100 FEET FOR COPPER TUBE2Col3 Col4 Col5 Col6 FLOW
RATE
(SCFM)13⁄4 INCH
TUBE1 INCH
TUBE11⁄4 INCH
TUBE11⁄2 INCH
TUBE2 INCH
TUBE49.43 – – – 3.645 0.956 52.97 – – – 4.122 1.081 56.50 – – – 4.626 1.212 63.56 – – – – 1.495 70.62 – – – – 1.803 77.68 – – – – 2.138 84.74 – – – – 2.497 91.81 – – – – 2.882 98.87 – – – – 3.291 105.93 – – – – 3.724 112.99 – – – – 4.181 CBC § 105.5.49 High relevance — show source text
Defined 202
Permit 105.5.49, 105.6.23 Ventilation 2403.3.5.2 Spraying Space Defined 202 Sprinkler Express Riser 202 Sprinkler System (see Automatic Sprinkler System) Stage Canopy, Temporary (see Temporary Stage Canopy) Stages, Fire Protection for 905.3.4, 914.6 Stairway 1011 Accessible means of egress 1009.2, 1009.3, 1009.6 Capacity 1005.3.1 Exit, exterior 1027 Exit, interior 1023, 1024, 1025 Exit access 1019
Identification 1023.8, 1023.9, 1104.21,
1104.24 On flammable and combustible liquid loading racks 5706.5.1.12 On flammable and combustible liquid storage tanks 5704.2.9.4 Roof access 1011.2 Spiral stairways 1011.10 Standby Personnel (see Fire Watch)
3108.16
Standby Power System 202, 1203, 5005.1.5 Accessible means of egress 1009.4.1 Elevators 604.3 Emergency voice/alarm communications systems 907.5.2.2.5 Energy storage systems (ESS) 1207.6.1.2.1 Gas detection systems 916.5, 1207.6.1.2.4
Hazardous materials 5004.7, 5005.1.5 Higher education laboratory 3804.1.1.6
Hoistway pressurization systems 909.21.5 Hydrogen storage rooms 5808.7 In-building emergency responder communications system 510.4.2.3 Organic peroxides 6204.1.11 Platform lifts 1009.5 Smoke control systems 909.11 Pressurized stairways 909.20.5.2 Special purpose doors 1010.3.3 Stairway and ramp ventilation systems 909.20.5.2
Standpipes 905 Buildings under construction/ demolition 3307.5
Classes of 202
Dry 905.8 Existing buildings 1103.6, 1103.6.1 Heliports and helistops 905.3.5, 1103.6.2, 2007.5 Landscaped roofs 905.3.7 Permit 105.6.24 Rooftop gardens 905.3.7 Types 202 Static Piles (wood products) 202 Protection 2808.6
Static Protection 5706.5.1.7 Stationary Storage Battery Systems (see Battery System, Stationary Storage) Stills, Dry Cleaning 2104.2.4, 2107.1 Stop Work Order 114 Storage Aerosol, inside 5104 Ammunition 5606
Attics 315.3.4
Automated 3209
Boiler rooms 315.3.3
Calcium carbide 3507.1
Carousel 3209.3 Combustible fibers, baled 3705 Combustible fibers, detached structure
CBC § 43-7 High relevance — show source text
2, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, Joint Fire Research Organization, London, HMSO, 1961. 116. Robinson, W. C., The Parker Building Fire, Underwriters’ Laboratories, Chicago, c. 1908. 117. Ferris, J. E., “Fire Hazards of Combustible Wallboards,” Commonwealth Experimental Building Station Special Report, No. 18, Sydney, Oct. 1955. 118. Markwardt, L. J., Bruce, H. D., and Freas, A. D., “Brief Description of Some Fire-Test Methods Used for Wood and WoodBased Materials,” Forest Service Report, No. 1976, Forest Products Laboratory, Madison, 1976. 119. Foster, H. D., Pinkston, E. R., and Ingberg, S. H., “Fire Resistance of Walls of Gravel-Aggregate Concrete Masonry Units,” Building Materials and Structures, Report, BMS 120, National Bureau of Standards, Washington, March 1951. 120. Foster, H. D., Pinkston, E.R., and Ingberg, S. H., “Fire Resistance of Walls of Lightweight-Aggregate Concrete Masonry Units,” Building Materials and Structures, Report BMS 117, National Bureau of Standards, Washington, May 1950. 121. Structural Clay Products Institute, “Structural Clay Tile Fireproofing,” Technical Notes on Brick & Tile Construction, vol. 1, no. 11, San Francisco, Nov. 1950.
Structural Clay Products Institute, “Fire Resistance Ratings of Clay Masonry Walls—I,” Technical Notes on Brick & Tile Construction, vol. 3, no. 12, San Francisco, Dec. 1952.
Structural Clay Products Institute, “Estimating the Fire Resistance of Clay Masonry Walls—II,” Technical Notes on Brick & Tile Construction, vol. 4, no. 1, San Francisco, Jan. 1953.
Building Research Station, “Fire: Materials and Structures,” Digest, No. 106, London, HMSO, 1958.
Mitchell, N. D., “Fire Hazard Tests with Masonry Chimneys,” NFPA Publication, No. Q-43-7, Boston, Oct. 1949.
Clinton Wire Cloth Company, Some Test Data on Fireproof Floor Construction Relating to Cinder Concrete, Terra Cotta and Gypsum, Clinton, 1913.
Structural Engineers Association of Southern California, Fire Ratings Subcommittee, “Fire Ratings, a Report,” part of Annual Report, Los Angeles, 1962, pp. 30-38.
Lawson, D. I., Fox, L. L., and Webster, C. T., “The Heating of Panels by Flue Pipes,” Fire Research, Special Report, No. 1, Dept. of Scientific and Industrial Research and Fire Offices’ Committee, London, HMSO, 1952.
Forest Products Laboratory, “Fire Resistance of Wood Construction,” excerpt from “Wood Handbook—Basic Information on Wood as a Material of Construction with Data for its Use in Design and Specification,” Dept. of Agriculture Handbook, No. 72, Washington, 1955, pp. 337-350.
Goalwin, D. S., “Properties of Cavity Walls,” Building Materials and Structures, Report BMS 136, National Bureau of Standards, Washington, May 1953.
CBC § 5.3 High relevance — show source text
5.3,
A5.106.11.2.3| |ASTM E2921-2022
|Standard Practice for Minimum Criteria for Comparing Whole Building Life Cycle
Assessments for Use with Building Codes, Standards, and Rating Systems
|5.409.2, A5.409.2| |CSACanadian Standards Association, 5060 Spectrum Way, Suite 100 Mississauga, Ontario, Canada L4W 5N6
www.csa.ca|~~**CSA~~ Canadian Standards Association, 5060 Spectrum Way, Suite 100 Mississauga, Ontario, Canada L4W 5N6
www.csa.ca|~~CSA~~ Canadian Standards Association, 5060 Spectrum Way, Suite 100 Mississauga, Ontario, Canada L4W 5N6
www.csa.ca| |CSA B125.1|Plumbing supply fittings|4.504.5.1| |CSA O121|Douglas fir plywood|4.504.5.1| |CSA O151|Canadian softwood plywood|4.504.5.1| |CSA O153|Poplar plywood|4.504.5.1| |CSA O325
|Construction sheathing
|4.504.5.1| |~~ENEuropean Standards, European and International standards online store - European StandardsEN
www.en-standard.eu|European Standards, European and International standards online store - European StandardsEN
www.en-standard.eu|European Standards, European and International standards online store - European StandardsIAPMO~~ International Association of Plumbing and Mechanical Officials, 4755 E. Philadelphia St. Ontario, CA 91761
www.en-standard.eu| |EN 15804-2012 + A2:2019|Sustainability of construction works. Environmental product declarations. Core
rules for the product category of construction products|5.409.2, A5.409.2.1,
A5.409.2.2| |EN 15978:2011
|Sustainability of construction works. Assessment of environmental performance of
buildings. Calculation method
|5.409.2, A5.409.2.1,
A5.409.2.2| |
iapmo@iapmo.org|~~IAPMO~~ International Association of Plumbing and Mechanical Officials, 4755 E. Philadelphia St. Ontario, CA 91761
iapmo@iapmo.org|~~IAPMO~~ International Association of Plumbing and Mechanical Officials, 4755 E. Philadelphia St. Ontario, CA 91761
iapmo@iapmo.org| |IAPMO Z124.9
|Plastic Plumbing Fixtures
|5.303.6| |~~IESNA~~ Illuminating Engineering Society of North America, 170 Wall St. Floor 17, New York, NY 10005-4001
http://www.ies.org|~~IESNA~~ Illuminating Engineering Society of North America, 170 Wall St. Floor 17, New York, NY 10005-4001
http://www.ies.org|~~IESNA**~~ Illuminating Engineering Society of North America, 170 Wall St. Floor 17, New York, NY 10005-4001
http://www.ies.org| |IES TM-15-11
|Luminaire Classification System for Outdoor Luminaires
|5.10,CBC § 507.25 High relevance — show source text
507.25, 508.4
Approval requirements . . . . . . . . . . . . . . . . . . . . . .501.1 Approved standards . . . . . .Table 501.1(1), 505.3, 505.4 Clearances. . . . . . . . . . . . . . . . . . . . . . 504.3 – 504.3.2,
508.1, 508.2.1
Combustion air required . . . . . . . . . . . . . . . . . . . .506.0
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .604.13
Dual purpose, definition . . . . . . . . . . . . . . . . . . . .225.0
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225.0
Garages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507.13 Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .503.2
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507.0
Location . . . . . . . . . . . . . . . . . . .504.1, 507.12 – 507.15
Oil-burning and other . . . . . . . . . . . . . . . . . . . . . .505.0 Permits required . . . . . . . . . . . . . . . . . . . . . . . . . .502.0
Pressure-relief valves . . . . . . . . . . .504.4, 504.6, 505.2,
608.2 – 608.5
Protection . . . . . . . . . . . . . . . . . . .504.3 – 504.6, 505.2,
507.2, 507.8, 507.10,
507.14.1, 507.24
Relief valve discharge . . . . . . . . . . . . . . . . . . . . . .608.5 Seismic provisions . . . . . . . . . . . . . . . . . . . . . . . . .507.2 Temperature and pressure-relief valves . . . . . . . . . . . . . . .504.6, 505.2 Temperature-limiting devices . . . . . . . . . . . . . . . . .504.5
Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.0, 510.0
Water heating system requirements . . . . . . . . . . . .501.2 WATER SOFTENERS . . . . . . . . . . . . . . . . 611.4, Table 611.4
CBC § 304.8 High relevance — show source text
6940
6730
6030
4940
4290|7940
7690
6880
5620
4870| |250
300
400
500|49
44
38
34|67
61
52
46|121
110
96
86|141
129
111
100|236
217
189
170|284
260
225
202|497
453
390
348|576
525
453
404|941
862
749
552|1090
999
871
783|1890
1720
1490
1330|2180
1990
1730
1550|3850
3520
3060
2740|4360
3980
3450
3090|For SI units: 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m [3] /h, 1 pound-force per square inch = 6.8947 kPa
Notes: 1 Table does not include effect of pressure drop across the line regulator. Where regulator loss exceeds 0.75 psi (5.17 kPa), DO NOT USE THIS TABLE. Consult with regulator manufacturer for pressure drops and capacity factors. Pressure drops across a regulator are capable of varying with flow rate. 2 CAUTION: Capacities shown in table are capable of exceeding maximum capacity for a selected regulator. Consult with regulator or tubing manufacturer for guid ance. 3 Table includes losses for four 90 degree (1.57 rad) bends and two end fittings. Tubing runs with larger numbers of bends, fittings, or both shall be increased by an equivalent length of tubing according to the following equation: L = 1.3 n, where L is additional length (ft) of tubing and n is the number of additional fittings, bends, or both. 4 Table entries are rounded to 3 significant digits. 5 EHD = Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.
2025 CALIFORNIA PLUMBING CODE 253
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FUEL GAS PIPING
CBC § 3.2.2 High relevance — show source text
1810 A .3.2.2 Prestressing steel. Prestressing steel shall conform to ASTM A416.
1810 A .3.2.3 Steel. Structural steel H-piles and structural steel sheet piling shall conform to the material requirements in ASTM A6. Steel pipe piles shall conform to the material requirements in ASTM A252. Fully welded steel piles shall be fabricated from plates that conform to the material requirements in ASTM A36, ASTM A283, ASTM A572, ASTM A588 or ASTM A690.
1810 A .3.2.4 Timber. Not permitted by DSA-SS, DSA-SS/CC or OSHPD.
1810 A .3.2.5 Protection of materials. Where boring records or site conditions indicate possible deleterious action on the materials used in deep foundation elements because of soil constituents, changing water levels or other factors, the elements shall be adequately protected by materials, methods or processes approved by the building official. Protective materials shall be applied to the elements so as not to be rendered ineffective by installation. The effectiveness of such protective measures for the particular purpose shall have been thoroughly established by satisfactory service records or other evidence.
1810 A .3.2.6 Allowable stresses. The allowable stresses for materials used in deep foundation elements shall not exceed those specified in Table 1810 A .3.2.6.
TABLE 1810A.3.2.6—ALLOWABLE STRESSES FOR MATERIALS USED IN DEEP FOUNDATION ELEMENTS Col2 MATERIAL TYPE AND CONDITION MAXIMUM ALLOWABLE STRESSa 1. Concrete or grout in compressionb
Cast-in-place with a permanent casing in accordance with Section 1810_A_.3.2.7
or Section 1810_A_.3.5.3.4
Cast-in-place in other permanent casing or rock
Cast-in-place without a permanent casing
Precast nonprestressed
Precast prestressed0.4_f ′c_
0.33_f ′c_
0.3_f ′c_
0.33_f ′c_
0.33_f ′c_ - 0.27_fpc_2. Nonprestressed reinforcement in compression 0.4_fy_ ≤ 30,000 psi 3. Steel in compression
Cores within concrete-filled pipes or tubes
Pipes, tubes or H-piles, where justified in accordance with Section 1810.3.2.8
Pipes or tubes for micropiles
Other pipes, tubes or H-piles
Helical piles0.5_Fy_ ≤ 32,000 psi
0.5_Fy ≤ 32,000 psi
0.4_Fy ≤ 32,000 psi
0.35_Fy_ ≤ 24,000 psi
0.6_Fy_ ≤ 0.5_Fu_4. Nonprestressed reinforcement in tension
Within micropiles
Other conditions
For load combinations that do not include wind or seismic loads
For load combinations that include wind or seismic loads0.6_fy_
0.5_fy_ ≤ 30,000 psi
0.5_fy_ ≤ 40,000 psi5. CBC § 312.1.1 High relevance — show source text
Barns
Carports Communication equipment structures with a gross floor area of less than 1,500 square feet (139 m [2] )
Fences more than 7 feet (2134 mm) in height
Grain silos, accessory to a residential occupancy
Livestock shelters
Private garages
Retaining walls
Sheds
Stables
Tanks
Towers
312.1.1 Greenhouses. Greenhouses not classified as another occupancy shall be classified as Use Group U.
312.2 Private garages and carports. Private garages and carports shall comply with Section 406.3.
312.3 Residential aircraft hangars. Aircraft hangars accessory to a one- or two-family residence shall comply with Section 412.4.
SECTION 313—LABORATORIES GROUP L [SFM]
313.1 Group L Laboratories. [SFM] Group L occupancy includes the use of a building or structure, or a portion thereof, containing one or more laboratory suites as defined in Section 453.
SECTION 314—ORGANIZED CAMPS GROUP C [SFM]
314.1 Organized Camps Group C. [SFM] An organized camp is a site with programs and facilities established for the primary purpose of providing an outdoor group living experience with social, spiritual, educational or recreational objectives, for five days or more during one or more seasons of the year.
2025 CALIFORNIA BUILDING CODE 3-19
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
3-20 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE
CHAPTER 4 – SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt entire chapter X X X X X X X X X Adopt entire chapter as
amended (amended sections
listedCBC § 1617A.1.41. High relevance — show source text
Class 1. An oxidizer that does not moderately increase the burning rate of combustible materials.
[F] OXIDIZING GAS. A gas that can support and accelerate combustion of other materials more than air does.
[BS] PANEL (PART OF A STRUCTURE). The section of a floor, wall or roof comprised between the supporting frame of two adjacent rows of columns and girders or column bands of floor or roof construction.
[BE] PANIC HARDWARE. A door-latching assembly incorporating a device that releases the latch upon the application of a force in the direction of egress travel. See “Fire exit hardware.”
[BS] PARTICLEBOARD. A generic term for a panel primarily composed of cellulosic materials (usually wood), generally in the form of discrete pieces or particles, as distinguished from fibers. The cellulosic material is combined with synthetic resin or other suitable bonding system by a process in which the interparticle bond is created by the bonding system under heat and pressure.
PASSAGE DOOR. [HCD 1-AC] A door other than an exit door through which persons may traverse.
PASSENGER ELEVATOR. [DSA-AC] See “Elevator, Passenger”
PASSENGER ELEVATOR. [HCD 1 & HCD 2] An elevator used primarily to carry passengers. For additional information, see California Code of Regulations, Title 8, Division 1, Chapter 4.
PASSIVE SOLAR ENERGY COLLECTOR. [HCD 1 & HCD 2] Uses architectural components, rather than mechanical components, to provide heating or cooling for a building interior.
PATH OF TRAVEL. [DSA-AC] An identifiable accessible route within an existing site, building or facility by means of which a particular area may be approached, entered and exited, and which connects a particular area with an exterior approach (including sidewalks, streets and parking areas), an entrance to the facility, and other parts of the facility. When alterations, structural repairs or additions are made to existing buildings or facilities, the term “path of travel” also includes the toilet and bathing facilities, telephones, drinking fountains and signs serving the area of work.
PEDESTRIAN. [HCD 1-AC] An individual who moves in walking areas with or without the use of walking assistive devices such as crutches, leg braces, wheelchairs, white cane, service animal, etc.
PEDESTRIAN WAY. A route by which a pedestrian may pass.
PEER REVIEW. [OSHPD 1, 1R, 2, 4 & 5] Peer review refers to the procedure contained in California Building Code Section 1617A.1.41.
[A] PEER REVIEW. An independent and objective technical review conducted by an approved third party.
[BF] PENETRATION FIRESTOP. A through-penetration firestop or a membrane-penetration firestop.
[BG] PENTHOUSE. An enclosed, unoccupiable rooftop structure used for sheltering mechanical and electrical equipment, tanks, elevators and related machinery, stairways, and vertical shaft openings.
[BS] PERFORMANCE CATEGORY. A designation of wood structural panels as related to the panel performance used in Chapter 23.
CBC § 301.1 High relevance — show source text
ICC code development note: Code change proposals to sections preceded by the designation [F] will be considered by the IFC code development committee meeting during the 2024 (Group A) Code Development Cycle. All other code change proposals will be considered by a code development committee meeting during the 2025 (Group B) Code Development Cycle.
SECTION 301—SCOPE
301.1 General. The provisions of this chapter shall control the classification of all buildings and structures as to occupancy and use. Different classifications of occupancy and use represent varying levels of hazard and risk to building occupants and adjacent properties.
SECTION 302—OCCUPANCY CLASSIFICATION AND USE DESIGNATION
302.1 Occupancy classification. Occupancy classification is the formal designation of the primary purpose of the building, structure or portion thereof. Structures shall be classified into one or more of the occupancy groups specified in this section based on the nature of the hazards and risks to building occupants generally associated with the intended purpose of the building or structure. An area, room or space that is intended to be occupied at different times for different purposes shall comply with all applicable requirements associated with such potential multipurpose. Structures containing multiple occupancy groups shall comply with Section 508. Where a structure is proposed for a purpose that is not specified in this section, such structure shall be classified in the occupancy it most nearly resembles based on the fire safety and relative hazard. Occupiable roofs shall be classified in the group that the occupancy most nearly resembles, according to the fire safety and relative hazard, and shall comply with Section 503.1.4.
- Assembly (see Section 303): Groups A-1, A-2, A-3, A-4 and A-5.
- Business (see Section 304): Group B. 3. [SFM] Organized Camps (see Section 450): Group C. 4. Educational (see Section 305): Group E. 5. Factory and Industrial (see Section 306): Groups F-1 and F-2. 6. High Hazard (see Section 307): Groups H-1, H-2, H-3, H-4 and H-5. 7. Institutional (see Section 308): Groups I-2, I-3 and I-4. 8. [SFM] Laboratory (see Section 202): Group B, unless classified as Group L (see Section 453) or Group H (see Section 307). 9. [SFM] Laboratory Suites (see Section 453): Group L. 10. Mercantile (see Section 309): Group M. 11 . Residential (see Section 310): Groups R-1, R-2, R-2.1, R-3, R-3.1 and R-4. 12 . Storage (see Section 311): Groups S-1 and S-2. 13 . Utility and Miscellaneous (see Section 312): Group U. 14. [SFM] Existing buildings housing existing protective social care homes or facilities established prior to 1972 (see California Fire Code Chapter 11 and California Existing Building Code).
302.1.1 Reserved
302.1.2 Reserved
302.1.3 Pharmacies; veterinary facilities; barbering, cosmetology or electrolysis establishments; and acupuncture offices. See Chapter 12.
Frequently asked questions
What is the minimum ventilation I must design for a teaching lab?
Design for the greater of 1 cfm per sq ft of floor area or 6 air changes per hour, and the system must operate continuously (CBC § 453.4.7.5) .
Can laboratory exhaust be tied into the building return air?
No. Laboratory suite exhaust air shall not be recirculated and must be independently ducted to outdoors or an approved rooftop structure (CBC § 453.4.7.4.1–.4.2) .
Do exit doors from hazardous labs have to swing out?
Yes. All exit and exit‑access doors serving areas with hazardous materials must swing in the direction of exit travel (CBC § 453.6.2) .
My lab is 320 sq ft with hazardous chemicals—do I need two exits?
Not by the 500 sq ft threshold in § 453.6.1; rooms containing hazardous materials must have access to two exits only when the floor area is 500 sq ft or more (CBC § 453.6.1) .
Where do I find the allowable percentage of MAQ for my floor level?
Consult Table 453.7.2.1 (CBC § 453.7.2). The uploaded preview did not include the numeric percentages, so use the full CBC Table 453.7.2.1 for the exact per‑story percentage limits (CBC § 453.7.2 and Table 453.7.2.1) .
More in California Building Code
- Administration & Permits
- Energy Efficiency
- Existing Buildings
- Occupancy Classification & Use
- Hazardous Materials & Occupancies
- Types of Construction
- Fire-Resistance & Fire Safety
- Interior Finishes
- Means of Egress
- Accessibility
- Exterior Walls
- Roofing & Roof Assemblies
- Structural Design
- Special Inspections & Tests
- Foundations & Soils
- Concrete
- Masonry
- Steel
- Wood
- Elevators & Conveying Systems
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