CRSC · California Referenced Standards Code

What referenced reports and standards apply to radiation shielding for X‑ray and accelerator facilities?

If a clinic or facility installs dental X‑ray, medical X‑ray/gamma, or particle accelerator equipment in California, the California Referenced Standards Code requires you to design and evaluate shielding using the named NCRP reports — Report 35 for dental, Report 49 for medical X‑ray/gamma up to 10 MeV, and Report 51 for accelerators 0.1–100 MeV (see **§ 12-31C-101**) — and any variance must be handled through the Department of Health Services.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

The California Referenced Standards Code requires that all radiation shielding barriers in rooms and enclosures housing radiation machines comply with the mandatory standards and appendices in three specific NCRP reports: Report No. 35, Report No. 49, and Report No. 51. This requirement is the text of § 12-31C-101.

The single most important rule: use the NCRP reports listed in § 12-31C-101 for any design or evaluation of shielding for dental X‑ray, medical X‑ray/gamma, and particle‑accelerator facilities.

Requirements in detail

Which documents are mandated by the CRSC (quick list)

  • NCRP Report No. 35 — “Dental X‑RAY Protection” (mandatory for dental X‑ray shielding). § 12-31C-101.
  • NCRP Report No. 49 — “Structural Shielding Design and Evaluation for Medical use of X‑rays and Gamma Rays of Energies up to 10 MeV.” § 12-31C-101.
  • NCRP Report No. 51 — “Radiation Protection Design Guidelines for 0.1–100 MeV Particle Accelerator Facilities.” § 12-31C-101.

The CRSC text explicitly names these three reports (including the energy ranges where applicable) as the mandatory standards to which shielding barriers must conform.

Decision‑relevant matrix (what to pick and where to look)

Situation / equipment Typical energy range or class Which NCRP report to use Code Reference
Dental intraoral, panoramic, dental cone‑beam Dental X‑ray energies (typical diagnostic dental kVp ranges) NCRP Report No. 35 (Dental X‑RAY Protection) § 12-31C-101
Medical diagnostic or therapeutic X‑ray / gamma up to 10 MeV Up to 10 MeV NCRP Report No. 49 (Structural Shielding Design and Evaluation for Medical use of X‑rays and Gamma Rays of Energies up to 10 MeV) § 12-31C-101
Particle accelerators, cyclotrons, linacs with energies 0.1–100 MeV 0.1–100 MeV NCRP Report No. 51 (Radiation Protection Design Guidelines for 0.1–100 MeV Particle Accelerator Facilities) § 12-31C-101
Publisher / reference contact — National Council on Radiation Protection and Measurements, 7910 Woodmont Avenue, Bethesda, MD 20814 (as cited in the code) § 12-31C-101

Notes:

  • The CRSC text requires compliance with the mandatory standards and appendices in those Reports (not merely the general guidance). Design work must therefore follow the methods, tables, and appendices contained in the specified NCRP reports.

Who may grant exceptions (related administrative point)

The California Building Code cross‑references the CRSC requirement and states that the Department of Public Health / Department of Health Services is the agency that may grant a variance or exception to these standards (see the Building Code discussion at Section 3102C). For administrative exceptions or variances consult the department named in the Building Code.

Exceptions & special cases

  • The CRSC text of § 12-31C-101 itself does not list exceptions — it mandates compliance with the named NCRP reports.
  • Administrative variances or exceptions are not given in § 12-31C-101; they are handled by the Department of Health Services per the Building Code cross‑reference (see § 3102C in the California Building Code). If you believe a variance is needed, follow the DHS process referenced in the Building Code.
  • The code text cites specific NCRP reports by number and title; substituting different guidance or older/newer guidance is not authorized by § 12-31C-101 unless the Department grants a variance.

If you need to know whether a later NCRP edition supersedes the numbered reports cited, that determination must be made through the Department (variance/interpretation) because § 12-31C-101 mandates those reports by name.

Common mistakes

  • Assuming the CRSC gives calculation formulas or thickness tables directly — it does not; it mandates the NCRP reports as the standards to perform those calculations. Always consult the full text and appendices of the relevant NCRP report for computations.
  • Using the wrong report for the equipment class: e.g., using Report No. 35 (dental) for a linac or cyclotron. Match the equipment energy/class to the correct NCRP report (Report 35 = dental; Report 49 = medical X‑ray/gamma ≤ 10 MeV; Report 51 = accelerators 0.1–100 MeV).
  • Forgetting to include the Reports’ appendices: § 12-31C-101 requires compliance with the “mandatory standards and appendices” of those reports — appendices can contain essential tables and methods.
  • Assuming local building plan reviewers can approve an alternate standard without DHS concurrence — variances are administered by the Department per the Building Code cross‑reference.

Worked example — selecting the correct referenced report (with numbers)

Scenario: A clinic is installing three pieces of equipment:

  1. A dental panoramic and intraoral suite operating at 70 kVp.
  2. A diagnostic X‑ray room with equipment capable of up to 150 kVp.
  3. A small research linac that can deliver electrons / photons at 20 MeV.

How to apply § 12-31C-101:

  • For the dental suite (70 kVp) use NCRP Report No. 35 (dental shielding). The CRSC explicitly names Report No. 35 for dental installations. § 12-31C-101.
  • For the diagnostic room at 150 kVp (well below 10 MeV), use NCRP Report No. 49, which covers X‑rays and gamma rays of energies up to 10 MeV. § 12-31C-101.
  • For the linac at 20 MeV, use NCRP Report No. 51, which covers particle accelerators in the 0.1–100 MeV range. § 12-31C-101.

What you still must do (and where the numbers come from):

  • For each room you must compute barrier requirements (workload, use factor, distance, occupancy, required design dose limits, attenuation coefficients, tenth‑value layers, etc.) using the methods, tables, and appendices in the appropriate NCRP report cited by § 12-31C-101. The CRSC does not reproduce those calculation procedures — it requires you to follow the NCRP reports.

Related provisions

  • § 12-31C-101 — Mandatory reference of NCRP Reports No. 35, 49, and 51 (the controlling CRSC section).
  • California Building Code § 3102C — Cross‑reference stating that radiation shielding barriers must meet the requirements of § 12-31C-101 and that the Department of Health Services is the agency that may grant variances (see Building Code text).

(If you need the exact calculation steps or tables to compute barrier thicknesses, procure the appropriate NCRP report cited in § 12-31C-101 and follow its methods and mandatory appendices. The CRSC text names the reports but does not reproduce the calculation tables.)

Code references

Grounded in the retrieved California Referenced Standards Code — click a citation to read the verbatim passage:

  • CRSC § 436.5. High relevance — show source text

    DEPARTMENT OF HEALTH SERVICES

    Authority: Sections 102, 208 and 25811.

    Reference: Sections 102, 208 and 436.5.

    ALL HEALING ARTS X-RAY INSTALLATIONS

    Sec. 12-31C-101. All radiation shielding barriers in rooms and enclosures housing radiation machines shall comply with the mandatory standards and appendices in Report No. 35, “Dental X-RAY Protection”; Report 49, “Structural Shielding Design and Evaluation for Medical use of X-rays and Gamma Rays of Energies up to 10 MeV”; and Report No. 51, “Radiation Protection Design Guidelines for 0.1-100 MeV Particle Accelerator Facilities.” Published by the National Council on Radiation Protection and Measurements, 7910 Woodmont Avenue, Bethesda, Maryland 20814.

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    12-71 AIR FILTERS

    STANDARD 12-71-1

    STATE FIRE MARSHAL

    DESCRIPTION OF TEST APPARATUS, METHOD AND CLASSIFICATION REQUIREMENTS FOR AIR FILTERS

    Sec. 12-71-100.

    (a) Test apparatus.

    1. The test duct, made of M.S. gage galvanized sheet metal reinforced with angle irons, is 21 inches square (13 548 mm [2] ) and 13 [1] / 2 feet (4114 mm) long.
    2. One end of the duct is tapered to the discharge of a variable-speed blower and the other end is open to discharge. A metal filter frame is provided near the middle of the length of the duct to receive one 20 by 20 inches (508 mm by 508 mm) (nominal) filter unit. Two tightfitting doors, located to permit access to the filter frame, are each provided with a mica window to permit observation of both faces of the filter and conditions in the duct downstream from the filter.
    3. Two 1-inch (25 mm) pipe elbows, about 18 inches (457 mm) from the base of the test filter, form gas burner outlets adjusted to provide yellow, wavering flames. The burners consume approximately 4 cubic feet (approximately 1,000 Btu/cubic feet) of gas per minute.
    4. With the filter in place the air velocity is adjusted to approximately 200 linear feet per minute as measured at the discharge end of the duct by an Alnor Velometer Anemometer.

    (b) Test method.

    1. Filters are tested clean, that is, unused. The flames are applied for 3 minutes during which time observations are made of both faces of the filter as to the downstream travel of flame or sparks and the density, duration and character of the products of combustion.
  • CRSC § 12-16 High relevance — show source text

    CALIFORNIA STANDARD FOR RESIDENTIAL EXCESS FLOW ACTUATED AUTOMATIC GAS SHUTOFF VALVES (SEE CCR TITLE 24, PART 5, CHAPTER 12) STANDARD 12-16-2

    DIVISION OF THE STATE ARCHITECT

    Authority: Sections 19200–19204, Health and Safety Code. Reference: Sections 19201.5 and 19202, Health and Safety Code.

    DIVISION 1—CONSTRUCTION

    SCOPE

    Sec. 12-16-201. The American Society for Testing and Materials (ASTM) F2138-12(2017) Standard Specification for Excess Flow Valves for Natural Gas Service, and the American National Standards Institute (ANSI) Z21.93-2017/CSA 6.30-2017 Excess Flow Valves for Natural and LP Gas with Pressure up to 5 psig, shall be the applicable standards used by the Division of the State Architect for certification of these devices.

    Sec. 12-16-201.1. Each installation of a customer-owned device that satisfies this standard shall be in accordance with the California Plumbing Code (CCR Title 24, Part 5).

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    12-31C RADIATION SHIELDING STANDARDS

    STANDARD 12-31C-1

    DEPARTMENT OF HEALTH SERVICES

    Authority: Sections 102, 208 and 25811.

    Reference: Sections 102, 208 and 436.5.

    ALL HEALING ARTS X-RAY INSTALLATIONS

    Sec. 12-31C-101. All radiation shielding barriers in rooms and enclosures housing radiation machines shall comply with the mandatory standards and appendices in Report No. 35, “Dental X-RAY Protection”; Report 49, “Structural Shielding Design and Evaluation for Medical use of X-rays and Gamma Rays of Energies up to 10 MeV”; and Report No. 51, “Radiation Protection Design Guidelines for 0.1-100 MeV Particle Accelerator Facilities.” Published by the National Council on Radiation Protection and Measurements, 7910 Woodmont Avenue, Bethesda, Maryland 20814.

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    12-71 AIR FILTERS

    STANDARD 12-71-1

    STATE FIRE MARSHAL

    DESCRIPTION OF TEST APPARATUS, METHOD AND CLASSIFICATION REQUIREMENTS FOR AIR FILTERS

    Sec. 12-71-100.

    (a) Test apparatus.

    1. The test duct, made of M.S. gage galvanized sheet metal reinforced with angle irons, is 21 inches square (13 548 mm [2] ) and 13 [1] / 2 feet (4114 mm) long.
  • CRSC § 1.11. High relevance — show source text

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    31C [DPH] RADIATION

    SECTION 3101C—SCOPE

    For the purpose of this chapter, the following terms shall have the meaning indicated:

    PRIMARY PROTECTIVE BARRIER is a barrier to attenuate the useful beam.

    SECONDARY PROTECTIVE BARRIER is a barrier to attenuate stray radiation.

    STRAY RADIATION is radiation not serving any useful purpose, which includes leakage and scattered radiation.

    USEFUL BEAM is the radiation which passes through the window, aperture, cone or other collimating device of the tube housing.

    SECTION 3102C—RADIATION SHIELDING BARRIERS

    All radiation shielding barriers in rooms and enclosures housing machines shall meet the requirements of Section 12-31C-101, Chapter 12-31C, Part 12, California Referenced Standards Code. The Department of Health Services is the only agency that may grant a variance or exception to these standards.

    SECTION 3103C—MEDICAL RADIOGRAPHIC AND PHOTOFLUOROGRAPHIC INSTALLATIONS

    3103C.1 Operator station. The operator’s station at the control shall be behind a protective barrier either in a separate room, in a protected booth or behind a shield which will intercept the useful beam and any radiation which has been scattered only once.

    3103C.2 Patient observation and communication. Provision shall be made for the operator to observe and communicate with the patient without leaving the shielded position at the control panel. When an observation window is used, it must provide radiation atten- uation equal to that required in the surrounding barrier.

    SECTION 3104C—MEDICAL THERAPEUTIC X-RAY INSTALLATIONS

    3104C.1 General. All wall, floor and ceiling areas that can be struck by the useful beam, plus a border of 1 foot (305 mm), shall be provided with primary protective barriers.

    3104C.2 Equipment operating above 50 kVp. Equipment operating above 50 kVp shall conform with the following: 1. The control station shielding shall either be an integral part of the building or anchored to the building. 2. The control station shall be provided with a window having radiation attenuation equal to that required by the adjacent barrier, or a mirror system, or a closed-circuit television viewing screen. The patient area must be visible to the operator with- out having to leave the protected area during exposure.

  • CRSC § 1.11. High relevance — show source text

    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 31C – RADIATION

    (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-
    CG    		 SFM 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-
    CG    		 SFM 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
    Adopt entire chapter as
    amended (amended
    sections listed below)
    Adopt only those sections
    that are listed below
    Chapter / Section

    The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

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    31C [DPH] RADIATION

    SECTION 3101C—SCOPE

    For the purpose of this chapter, the following terms shall have the meaning indicated:

    PRIMARY PROTECTIVE BARRIER is a barrier to attenuate the useful beam.

    SECONDARY PROTECTIVE BARRIER is a barrier to attenuate stray radiation.

    STRAY RADIATION is radiation not serving any useful purpose, which includes leakage and scattered radiation.

    USEFUL BEAM is the radiation which passes through the window, aperture, cone or other collimating device of the tube housing.

    SECTION 3102C—RADIATION SHIELDING BARRIERS

    All radiation shielding barriers in rooms and enclosures housing machines shall meet the requirements of Section 12-31C-101, Chapter 12-31C, Part 12, California Referenced Standards Code. The Department of Health Services is the only agency that may grant a variance or exception to these standards.

    SECTION 3103C—MEDICAL RADIOGRAPHIC AND PHOTOFLUOROGRAPHIC INSTALLATIONS

  • CRSC § 1224.34.3.2 High relevance — show source text

    but otherwise having the_ same functional characteristics as the above mega-voltage units and conforming to the requirements of Chap- ter 31C and the California Radiation Control Regulations, California Code of Regulations, Title 17, Division 1, Chapter 5, Subchapter 4. 5.3. Direct access to space provided for brachytherapy equipment which shall meet the requirements of Chapter 31C and the California Radiation Control Regulations, California Code of Regulations, Title 17, Division 1, Chap- ter 5, Subchapter 4. 5.4. Shielding of the rooms shall meet the requirements of Chapter 31C and the California Radiation Control Regula- tions. California Code of Regulations, Title 17, Division 1, Chapter 5, Subchapter 4.

    1224.34.3.2 Radiation protection. Cobalt, linear accelerators, hot lab and high dose rate brachytherapy rooms and simulation rooms require radiation protection. All rooms that provide radiation treatment shall be appropriately shielded. A certified physi- cist shall specify the type, location and amount of protection to be installed in accordance with final approved department layout and equipment selection. Radiation protection requirements shall be incorporated into the construction documents and comply with Chapter 31C and the requirements of California Radiation Control Regulations, California Code of Regulations, Title 17, Divi- sion 1, Chapter 5 and Subchapter 4.

    1224.34.3.3 Room sizes. Rooms shall be sized as follows:

    1. Cobalt rooms and linear accelerators shall be sized in accordance with equipment requirements and shall accommo- date a gurney for litter borne patients. Layouts shall provide for preventing the escape of radioactive particles. Openings into the room, including doors, ductwork, vents and electrical raceways and conduits, shall be baffled to prevent direct exposure to other areas of the facility. 2. Simulator, accelerator and cobalt rooms shall be sized to accommodate the equipment with patient access on a gurney, medical staff access to the equipment and patient, and service access. 3. Where a table is used, the room shall be sized to provide a minimum clearance of 4 feet (1218 mm) on three sides of the table to facilitate bed transfer and provide access to the patient. The door swing shall not encroach on the equipment space, patient circulation space or transfer space. 4. Minimum room size shall be 260 square feet (24.15 m [2] ) for the simulator room; 680 square feet (63.17 m [2] ), including the maze, for accelerator rooms; 200 square feet (18.58 m [2] ) for brachytherapy rooms; and 450 square feet (41.81 m [2] ) for cobalt rooms.

    1224.34.3.4 General support area. The following areas shall be provided: 1. A gurney hold area adjacent to the treatment rooms, screened for privacy and combined with a seating area for outpatients. 2. Exam or treatment room shall be provided with a minimum of 100 square feet (9.29 m [2] ) with a minimum dimension of 8 feet (2438 mm). Each exam room shall be equipped with a handwashing station.

  • CRSC § 1224.34 High relevance — show source text

    1224.34 NUCLEAR MEDICINE.

    1224.34.1 General. If nuclear medicine is provided, the following shall be provided:

    1224.34.1.1 Radiation protection. A certified physicist shall specify the type, location and amount of radiation protection to be installed in accordance with final approved department layout and equipment selection. A physicist report shall also address dosing areas and circulation paths of dosed patients, including within multi-bay scanner rooms. Radiation protection require- ments shall be incorporated into the construction documents and comply with Chapter 31C and the requirements of California Radiation Control Regulations, California Code of Regulations, Title 17, Division 1, Chapter 5, and Subchapter 4.

    1224.34.1.2 Nuclear medicine room. Shall be sized to accommodate the equipment and a gurney.

    When provided, the following facilities shall meet the requirements below:

    1224.34.1.2.1 Scintigraphy (Gamma Camera) Facilities. Shall include the following: 1. Scanner room. The scanner room shall provide a minimum clearance of 4 feet (1218 mm) at each side and the foot of the table.

    2. Handwashing stations shall be provided throughout the gamma camera suite at locations of patient contact and at locations where radiopharmaceutical materials are handled, prepared or disposed of.

    1224.34.1.2.2 Positron Emission Tomography (PET). Shall include the following: 1. Scanner room shall provide a minimum clearance of 4 feet (1218 mm) at each side and the foot of the table. Additional space shall be provided when PET is combined with CT and include compliance with Section 1224.18.3 and shielding requirements in Section 1224.34.1.1. 2. Cyclotron room. Where radiopharmaceuticals are prepared on-site, a cyclotron shall be provided. Cyclotron facilities shall be located in access-restricted areas. Shielding requirements for cyclotron facilities shall comply with Section 1224.34.1.1.

    3. Control room. If a control room is required based on the physicist’s report, it shall be provided with a full direct view of the patient in the PET scanner. 4. Patient uptake/cool-down room. A shielded room with access to a dedicated patient toilet, to accommodate radioac- tive waste, and lavatory shall be provided. 5. Handwashing stations shall be provided throughout the PET suite at locations of patient contact and at locations where radiopharmaceutical materials are handled, prepared or disposed of. 6. Pre-procedure patient care and recovery area shall be provided to accommodate at least two stretchers. This area shall comply with Section 1224.34.2.6. 7. Imaging equipment room shall be provided in support of the equipment provided.

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    INTERIOR ENVIRONMENT

    8. Contaminated (hot) soiled holding shall be provided and operationally integrated to minimize incidental exposure to ionizing radiation.

  • CRSC § 31B-22 High relevance — show source text

    3162B Anti-Entrapment Devices and Systems . . . . . . . . . . 31B-22

    CHAPTER 31C RADIATION . . . . . . . . . . . . . . . . . . . . . . . . . .31C-1

    3101C Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31C-3

    3102C Radiation Shielding Barriers . . . . . . . . . . . . . . . . . . . . . 31C-3

    3103C Medical Radiographic and Photofluorographic Installations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31C-3

    3104C Medical Therapeutic X-Ray Installations. . . . . . . . . . 31C-3

    CHAPTER 31D FOOD ESTABLISHMENTS. . . . . . . . . . . . . . .31D-1

    3101D Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31D-3

    3102D Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31D-3

    3103D Buildings and Structures. . . . . . . . . . . . . . . . . . . . . . . . . 31D-3

    CHAPTER 31E RESERVED. . . . . . . . . . . . . . . . . . . . . . . . . . .31E-1

    CHAPTER 31F MARINE OIL TERMINALS . . . . . . . . . . . . . . .31F-1

    3101F Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31F-3

    3102F Audit and Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31F-6

    3103F Structural Loading Criteria . . . . . . . . . . . . . . . . . . . . . 31F-19

    3104F Seismic Analysis and Structural Performance. . . . 31F-34

    3105F Mooring and Berthing Analysis and Design . . . . . . 31F-48

    3106F Geotechnical Hazards and Foundations . . . . . . . . . 31F-55

  • CRSC § 3103C.1 High relevance — show source text

    SECTION 3103C—MEDICAL RADIOGRAPHIC AND PHOTOFLUOROGRAPHIC INSTALLATIONS

    3103C.1 Operator station. The operator’s station at the control shall be behind a protective barrier either in a separate room, in a protected booth or behind a shield which will intercept the useful beam and any radiation which has been scattered only once.

    3103C.2 Patient observation and communication. Provision shall be made for the operator to observe and communicate with the patient without leaving the shielded position at the control panel. When an observation window is used, it must provide radiation atten- uation equal to that required in the surrounding barrier.

    SECTION 3104C—MEDICAL THERAPEUTIC X-RAY INSTALLATIONS

    3104C.1 General. All wall, floor and ceiling areas that can be struck by the useful beam, plus a border of 1 foot (305 mm), shall be provided with primary protective barriers.

    3104C.2 Equipment operating above 50 kVp. Equipment operating above 50 kVp shall conform with the following: 1. The control station shielding shall either be an integral part of the building or anchored to the building. 2. The control station shall be provided with a window having radiation attenuation equal to that required by the adjacent barrier, or a mirror system, or a closed-circuit television viewing screen. The patient area must be visible to the operator with- out having to leave the protected area during exposure.

    3104C.3 Equipment operating above 150 kVp. Equipment operating above 150 kVp shall conform to the following: 1. The treatment room shall be provided with interlocks so that when any door of the treatment room is opened, either the machine will shut off automatically or the radiation level within the room will be reduced to an average of not more than 2 milliroentgens per hour and a maximum of 10 milliroentgens per hour at a distance of one meter in any direction from the target. After such shutoff or reduction in output, it shall be possible to restore the machine to full operation only from the control panel. 2. The control station shall be within a protective booth or in an adjacent room.

    3104C.4 A minimum of one door shall be provided with an auxiliary means for being opened in case of power failure or mechanical breakdown, where large power-driven doors offer the only access to the room.

    3104C.5 A flashing red warning signal light energized only when the useful beam is on shall be located adjacent to the entrance(s) to a therapy room with equipment capable of operating above 500 kVp.

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    CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE

    CHAPTER 31D – FOOD ESTABLISHMENTS

    (Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

  • CRSC § 31B-20 High relevance — show source text

    3154B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-20

    3155B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-20

    3156B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-20

    3157B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-21

    3158B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-21

    3159B Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-21

    DIVISION II – PUBLIC SWIMMING POOLS. . . . . . . . . . . . . . .31B-21

    3160B Ground Fault Circuit Interrupters. . . . . . . . . . . . . . . . 31B-21

    3161B Wading Pools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31B-21

    3162B Anti-Entrapment Devices and Systems . . . . . . . . . . 31B-22

    CHAPTER 31C RADIATION . . . . . . . . . . . . . . . . . . . . . . . . . .31C-1

    3101C Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31C-3

    3102C Radiation Shielding Barriers . . . . . . . . . . . . . . . . . . . . . 31C-3

    3103C Medical Radiographic and Photofluorographic Installations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31C-3

    3104C Medical Therapeutic X-Ray Installations. . . . . . . . . . 31C-3

    CHAPTER 31D FOOD ESTABLISHMENTS. . . . . . . . . . . . . . .31D-1

    3101D Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31D-3

  • CRSC § 12-16 High relevance — show source text

    CHAPTER 12-16-1 ENGINEERING REGULATIONS—QUALITY

    AND DESIGN OF THE MATERIALS OF

    CONSTRUCTION . . . . . . . . . . . . . . . . . . . 101

    CHAPTER 12-16-2 ENGINEERING REGULATIONS—QUALITY

    AND DESIGN OF THE MATERIALS OF

    CONSTRUCTION . . . . . . . . . . . . . . . . . . . 103

    CHAPTER 12-31C RADIATION SHIELDING STANDARDS . . 105

    CHAPTER 12-71 AIR FILTERS. . . . . . . . . . . . . . . . . . . . . . . 107

    CHAPTER 12-72-1 PROTECTIVE SIGNALING SYSTEMS . . . 109

    CHAPTER 12-72-2 PROTECTIVE SIGNALING SYSTEMS . . . 123

    CHAPTER 12-72-3 PROTECTIVE SIGNALING SYSTEMS . . . 133

    HISTORY NOTE APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

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    PART 12 CROSS REFERENCE TABLE

    (Cross reference table is nonregulatory, intended only as an aid to the code user.)

    PART 12
    STANDARD    		 SUBJECT ADOPTING
    AGENCY    		 ASSOCIATED TITLE 24
    BUILDING STANDARD
    Chapter 12-3 Releasing systems for security bars in
    dwellings    		 SFM Part 2, Sections 1031.2.1, 1031.6, 1032.7
    Part 2.5, Sections R319.1.1 and R319.4.4
    Part 9, Sections 1031.2.1, 1031.6, 1032.7
    Appendix 4 Section 452.1.5 and Title 19 provisions 4.1, 4.2, 4.3,
    4.4, 4.5, 4.6 reprinted in Part 9
    Part 10, Section 505.4
    Chapter 12-4A Laboratory animal quarters standards DPH Part 2, Section 1236
    Chapter 12-4-1 Stage and Platforms SFM Part 2, Sections 410.2.7, 410.2.7.1, 410.2.7.2
    Part 9, Sections 105.6.51, 4809
    Chapter 12-7-1 Fire-resistive standards.
  • CRSC § 12-16 Medium relevance — show source text

    12-16-1 ENGINEERING REGULATIONS—QUALITY AND

    DESIGN OF THE MATERIALS OF CONSTRUCTION

    CALIFORNIA STANDARD FOR EARTHQUAKE-ACTUATED AUTOMATIC GAS SHUTOFF SYSTEMS (SEE CCR TITLE 24, PART 2, CHAPTERS 16 AND 16A, AND CCR TITLE 24, PART 5, CHAPTER 12) STANDARD 12-16-1

    DIVISION OF THE STATE ARCHITECT

    Authority: Sections 19180–19183, Health and Safety Code. Reference: Section 19182, Health and Safety Code.

    DIVISION 1—CONSTRUCTION

    SCOPE

    Sec. 12-16-101. The American Society of Civil Engineers (ASCE) requirements for “Earthquake-Actuated Automatic Gas Shutoff Devices,” ANSI/ASCE/SEI 25-16 (copyright 2016 by ASCE), shall be the applicable standard used by the Division of the State Architect for the certification of these devices.

    Sec. 12-16-101.1. Each installation of a customer-owned device that satisfies this standard shall be in accordance with the California Plumbing Code (CCR Title 24, Part 5).

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    12-16-2 ENGINEERING REGULATIONS—QUALITY AND

    DESIGN OF THE MATERIALS OF CONSTRUCTION

    CALIFORNIA STANDARD FOR RESIDENTIAL EXCESS FLOW ACTUATED AUTOMATIC GAS SHUTOFF VALVES (SEE CCR TITLE 24, PART 5, CHAPTER 12) STANDARD 12-16-2

    DIVISION OF THE STATE ARCHITECT

    Authority: Sections 19200–19204, Health and Safety Code. Reference: Sections 19201.5 and 19202, Health and Safety Code.

    DIVISION 1—CONSTRUCTION

    SCOPE

    Sec. 12-16-201. The American Society for Testing and Materials (ASTM) F2138-12(2017) Standard Specification for Excess Flow Valves for Natural Gas Service, and the American National Standards Institute (ANSI) Z21.93-2017/CSA 6.30-2017 Excess Flow Valves for Natural and LP Gas with Pressure up to 5 psig, shall be the applicable standards used by the Division of the State Architect for certification of these devices.

    Sec. 12-16-201.1. Each installation of a customer-owned device that satisfies this standard shall be in accordance with the California Plumbing Code (CCR Title 24, Part 5).

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    12-31C RADIATION SHIELDING STANDARDS

    STANDARD 12-31C-1

    DEPARTMENT OF HEALTH SERVICES

  • CRSC § 1224.34.2.4 Medium relevance — show source text

    1224.34.2.4 Waiting. Waiting areas shall be provided out of traffic, under staff control. If the department is routinely used for outpatients and inpatients at the same time, separate waiting areas shall be provided with screening or visual privacy between the waiting areas.

    1224.34.2.5 Dose administration area. Provide a dose administration area that is immediately accessible to the preparation area. Since as much as several hours may elapse for the dose to take effect, the area shall provide for visual privacy from other

    areas.

    1224.34.2.6 Pre-procedure/holding area. A pre-procedure/holding area for patients on gurneys or beds shall be provided out of traffic and under control of staff and may be combined with the dose administration area with visual privacy between the areas.

    1224.34.2.7 Patient dressing rooms. Patient dressing rooms shall be immediately accessible to the waiting area and procedure rooms. Each dressing room shall include a seat or bench, a mirror, and provisions for hanging patients’ clothing and for securing valuables.

    1224.34.2.8 Patient toilet room(s). Patient toilet rooms shall be reserved for nuclear medicine patients and shall be immediately accessible to waiting and procedure rooms.

    1224.34.2.9 Staff toilet rooms. Staff toilet rooms shall be readily accessible to the nuclear medicine laboratory.

    1224.34.2.10 Handwashing stations. Handwashing stations shall be located within each procedure room.

    1224.34.2.11 Control desk and reception.

    1224.34.2.12 Storage area for clean linen.

    1224.34.2.13 Soiled and contaminated material. Provisions with handwashing stations shall be made for holding soiled mate- rial. Separate provisions shall be made for holding contaminated material.

    1224.34.2.14 Hot lab for scintigraphy (gamma camera), PET and SPECT facilities. A securable area or room shall be provided in which radiopharmaceuticals can be safely stored and doses can be calculated and prepared. 1. A single hot lab shall be permitted to serve multiple scanners and nuclear medicine modalities. 2. The hot lab shall be shielded in compliance with Section 1224.34.1.1. 3. A source storage area, a dose area and a storage area for syringe shields shall be provided.

    1224.34.3 Radiotherapy service space.

    1224.34.3.1 Radiation therapy space. If radiation therapy is provided, the following shall be accommodated: 1. Patient reception and waiting areas. 2. Space for medical and physics staff functions. 3. Space for equipment and supplies. 4. Housekeeping room. 5. Direct access to space provided for radiation measurement and calibration equipment, including a calibration constancy instrument and access to a secondary standard dose meter.

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    INTERIOR ENVIRONMENT

    5.1. A megavoltage treatment unit capable of delivering x-rays or gamma rays of effective energy 500 KeV or more and conforming to the requirements of Chapter 31C and the California Radiation Control Regulations, Califor- _nia Code of Regulations,

Frequently asked questions

What exactly does § 12-31C-101 require?

It requires that all radiation shielding barriers for rooms/enclosures housing radiation machines comply with the mandatory standards and appendices in NCRP Report No. 35, No. 49, and No. 51 — as named in § 12-31C-101.

Which report do I use for a CT scanner or general diagnostic X‑ray?

Use NCRP Report No. 49 for medical X‑ray and gamma energies up to 10 MeV, unless your equipment is specifically a dental X‑ray (Report 35) or a particle accelerator (Report 51). § 12-31C-101.

Are there any exceptions allowed to using those NCRP reports?

The CRSC text does not list exceptions in § 12-31C-101. Administrative variances are handled by the Department of Health Services through the Building Code cross‑reference (see § 3102C).

Do I have to use the appendices in the NCRP reports?

Yes — § 12-31C-101 requires compliance with the mandatory standards and appendices of the listed reports.

Where can I get the NCRP reports cited in § 12-31C-101?

The CRSC cites the National Council on Radiation Protection and Measurements (NCRP) and gives the publisher contact (NCRP, 7910 Woodmont Avenue, Bethesda, MD 20814) in the text of § 12-31C-101.

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