CHAPTER 94
STEAM HEATING BOILERS, HOT WATER HEATING BOILERS AND
HOT WATER SUPPLY BOILERS
[Prior to 9/24/86, Labor, Bureau of [530]]
[Prior to 1/14/98, see Labor Services[347] Ch 46]
[Prior to 8/16/06, see 875—Ch 207]
875—94.1(89) Scope. This chapter shall apply to:
	94.1(1) Steam boilers for operation at pressures not exceeding 15 psig;
	94.1(2) Hot water heating boilers for operation at pressures not exceeding 160 psig or temperatures not exceeding 250° F at or near the boiler outlet;
	94.1(3) Hot water supply boilers for operation at pressures not exceeding 160 psig or temperatures not exceeding 210° F at or near the boiler outlet.
875—94.2(89) Codes adopted by reference.
	94.2(1) Installations from July 1, 1960, to June 30, 1983. Installations and reinstallations from July 1, 1960, to June 30, 1983, shall be constructed and installed in accordance with the ASME Code for Boilers and Pressure Vessels, Section IV (1960).
	94.2(2) Installations from July 1, 1983, to December 31, 1988. Installations and reinstallations from July 1, 1983, to December 31, 1988, shall be constructed and installed in accordance with ASME Code for Boilers and Pressure Vessels, Section IV (1983) and ASME Safety Code, CSD-1, Boiler Installations (1982), excluding the provisions for listing or labeling by a nationally recognized testing agency.
	94.2(3) Installations from January 1, 1989, to December 31, 1990. Installations and reinstallations from January 1, 1989, to December 31, 1990, shall be constructed and installed in accordance with ASME Code for Boilers and Pressure Vessels, Section IV (1986 with 1988 addenda) and ASME Safety Code, CSD-1, Boiler Installations (1982), excluding the provisions for listing or labeling by a nationally recognized testing agency.
	94.2(4) Installations from January 1, 1991, to June 30, 1996. Installations and reinstallations from January 1, 1991, to June 30, 1996, shall be constructed and installed in accordance with ASME Code for Boilers and Pressure Vessels, Section IV (1989 with 1990 addenda) and ANSI/ASME CSD-1 (1988), excluding the provisions for listing or labeling by a nationally recognized testing agency.
	94.2(5) Installations from July 1, 1996, to December 31, 1997. Installations and reinstallations from July 1, 1996, to December 31, 1997, shall be designed, manufactured, installed, inspected and stamped in accordance with the requirements of the ASME Code for Boilers and Pressure Vessels, Section IV (1992 with 1994 addenda) or with the requirements of recognized national or international standards such as DIN, BSI, JIS, or CSA. Only national and international standards acceptable to the division may be utilized. The boilers must comply with the requirements of ANSI/ASME CSD-1 (1995).
	94.2(6) Installations from January 1, 1998, to December 31, 2000. Installations and reinstallations from January 1, 1998, to December 31, 2000, shall be designed, manufactured, installed, inspected, and stamped in accordance with the requirements of the ASME Code for Boilers and Pressure Vessels, Section IV (1995 with 1997 addenda) or with the requirements of recognized national or international standards such as DIN, BSI, JIS, or CSA. Only national and international standards acceptable to the division may be utilized. The boilers must comply with the requirements of ANSI/ASME CSD-1 (1995 with 1997 addenda).
	94.2(7) Installations from January 1, 2001, to September 19, 2006. Installations and reinstallations from January 1, 2001, to September 19, 2006, shall be designed, manufactured, installed, inspected, and stamped in accordance with the requirements of the ASME Code for Boilers and Pressure Vessels, Section IV (1998 with 1999 and 2000 addenda) or with the requirements of recognized national or international standards such as DIN, BSI, JIS, or CSA. Only national and international standards acceptable to the division may be utilized. The boilers must comply with the requirements of ANSI/ASME CSD-1 (1998 with 1999 addenda).
	94.2(8) Installations on or after January 1, 2005—aluminum alloy sand castings. On or after January 1, 2005, new installations of boilers, including reinstalled boilers, may be designed, manufactured, installed, inspected, and stamped in accordance with the requirements of ASME Code Cases 2382-1, 2393, and 2394.
	94.2(9) Installations on or after September 20, 2006. Installations and reinstallations on or after September 20, 2006, shall be designed, manufactured, installed, inspected, and stamped in accordance with the requirements of the ASME Code for Boilers and Pressure Vessels, Section IV (2004 with 2005 addenda) or with the requirements of recognized national or international standards such as DIN, BSI, JIS, or CSA. Only national and international standards acceptable to the division may be utilized. The boilers must comply with the requirements of ANSI/ASME CSD-1 (2004).
875—94.3(89) General requirements. This rule applies to all objects covered by this chapter and installed prior to September 20, 2006.
	94.3(1) Instruments, fittings and controls mounted inside boiler jackets. Any or all instruments, fittings and controls required by this chapter may be installed inside of boiler jackets provided the water gage and pressure gage on a steam boiler or the thermometer and pressure gage on a water boiler are visible through an opening or openings at all times.
	94.3(2) Electrical code compliance.
	a. 	Wiring. All wiring for controls, heat-generating apparatus and other appurtenances necessary for the operation of the boiler or boilers shall be in accordance with the National Electric Code (1992). All boilers supplied with factory-mounted and factory-wired controls, heat-generating apparatus and other appurtenances necessary for the operation of the boilers shall be installed in accordance with the provisions of nationally recognized standards.
	b. 	Circuitry. The control circuitry shall be grounded and shall operate at 150 volts or less. One of the two following systems may be employed to provide the control circuit:
	(1)	Two-wire, nominal 120-volt system with separate equipment ground conductor as follows:
This system shall consist of the line, neutral and equipment ground conductors. The control panel frame and associated control circuitry metallic enclosures shall be electrically continuous and be bonded to the equipment ground conductor.
The equipment ground conductor and the neutral conductor shall be bonded together at their origin in the electrical system for objects installed prior to September 20, 2006.
The line side of the control circuit shall be provided with a time delay fuse sized as small as practicable.
	(2)	Two-wire, nominal 120-volt system obtained by using an isolation transformer as follows:
The two-wire control circuit shall be obtained from the secondary side of an isolation transformer, shall be electrically continuous and shall be bonded to a convenient cold water pipe. All metallic enclosures of control components shall be securely bonded to this ground control circuit wire. The primary side of the isolation transformer will normally be a two-wire source with a potential 230, 208 or 440 volts.
Both sides of the two-wire primary circuit shall be fused. The hot leg on the load side of the isolation transformer shall be fused as small as practicable, and shall not be fused above the rating of the isolation transformer.
	94.3(3) Safety and safety relief valve discharge piping. When a discharge pipe is used, its internal cross-sectional areas shall not be less than the full area of the valve outlet or of the total of the valve outlets discharging therein and shall be as short and straight as possible and so arranged as to avoid undue stress on the valve or valves. When an elbow is placed on a safety valve or safety relief valve discharge pipe, the elbow shall be located close to the valve outlet.
	94.3(4) Expansion and contraction. Provisions shall be made for the expansion and contraction of steam and hot water mains connected to boilers.
	94.3(5) Return pipe connections. The return pipe connections of each boiler supplying a gravity-return steam heating system shall be so arranged as to form a loop so that the water in each boiler cannot be forced out below the safe water level.
	94.3(6) Feed water connections.
	a. 	Feed water, makeup water or water treatment shall be introduced into a boiler through the return piping system. Alternatively, makeup water or water treatment may be introduced through an independent connection. The water flow from the independent feed water connection shall not discharge against parts of the boiler exposed to direct radiant heat from the fire. Makeup water or water treatment shall not be introduced through openings or connections provided for inspection, cleaning, safety valves, safety-relief valves, blowoffs, water columns, water gage glasses, pressure gages or temperature gages.
	b. 	The makeup water pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the return pipe system.
	94.3(7) Oil heaters.
	a. 	A heater for oil or other liquid harmful to boiler operation shall not be installed directly in the steam or water space within a boiler.
	b. 	Where an external-type heater for such service is used, means shall be provided to prevent the introduction into the boiler of oil or other liquid harmful to boiler operation.
	94.3(8) Bottom blowoff or drain valve.
	a. 	Each boiler shall have a bottom blowoff or drain pipe connection fitted with a valve or cock connected with the lowest water space practicable, with the minimum size of blowoff piping and valves as specified below:

Minimum Required Safety or Safety-Relief Valve Capacity (Pounds of Steam Per Hour)	Size of Blowoff Valves (Inches)	
Up to 500	¾	
501 to 1250	1	
1251 to 2500	1¼	
2501 to 6000	1½	
6001 and larger	2	
Note:  Multiply 1,000 by the relieving capacity in pounds of steam per hour to determine the Btu’s of safety relief valve discharge capacity.
	b. 	Any discharge piping connected to bottom blowoff or bottom drain connections shall be full size to the point of discharge.
875—94.4(89) Steam heating boilers installed before July 1, 1960. All steam heating boilers installed before July 1, 1960, shall be constructed and installed in accordance with this rule.
	94.4(1) Safety valves.
	a. 	Each steam boiler shall have one or more safety valves bearing the National Board “HV” stamp of the spring-pop type adjusted and sealed to discharge at a pressure not to exceed 15 psig. Seals shall be attached in a manner to prevent the valve from being taken apart without breaking the seal. The safety valves shall be arranged so that they cannot be set to relieve at a higher pressure than the maximum allowable working pressure of the boiler. For iron and steel bodied valves exceeding 2-inch pipe size, the drain hole or holes shall be tapped not less than 3/8-inch pipe size.
	b. 	The safety valves shall be located in the top or side of the boiler. They shall be connected directly to a tapped or flanged opening in the boiler, to a fitting connected to the boiler by a short nipple, to a Y-base, or to a valveless header connecting steam or water outlets on the same boiler. Coil or header type boilers shall have the safety valve located on the steam outlet end. Safety valves shall be installed with their spindles vertical. The opening or connection between the boiler and any safety valve shall have at least the area of the valve inlet.
	c. 	Safety valves ½-inch or more in diameter that are installed on a steam boiler shall have a hand-lifted device that will positively lift the disk from its seat at least 1/16 inch when there is no pressure in the boiler. The seats and disks shall be of noncorrosive material.
	d. 	Safety valves for a steam boiler shall be at least ½ inch unless the boiler and radiating surfaces consist of a self-contained unit. Safety valves shall not be larger than 4½ inches. The inlet opening shall have an inside diameter equal to or greater than the seat diameter.
	e. 	The minimum relieving capacity of the valve or valves shall be governed by the capacity marking on the boiler.
	f. 	The minimum valve capacity in pounds per hour shall be equal to the steam generation as specified in 875—subrules 92.7(9) and 92.7(10).
	g. 	The safety valve capacity for each steam boiler shall be such that with the fuel burning equipment operated at maximum capacity the pressure will not rise more than 5 percent above the maximum allowable working pressure.
	h. 	When operating conditions are changed or additional boiler heating surface is installed, the valve capacity shall meet the new conditions.
	94.4(2) Steam gages.
	a. 	Each steam boiler shall have a steam gage or a compound steam gage connected to its steam space, its water column, or to its steam connection. The gage or connection shall contain a siphon or equivalent device that will develop and maintain a water seal that will prevent steam from entering the gage tube. The connection shall be so arranged that the gage cannot be shut off from the boiler except by a cock placed in the pipe at the gage and provided with a tee or lever-handle arranged to be parallel to the pipe in which it is located when the cock is open. The connections to the boiler shall be not less than ¼-inch standard pipe size, but where steel or wrought-iron pipe or tubing is used, it shall be not less than ½-inch standard pipe size. The minimum size of a siphon, if used, shall be ¼-inch inside diameter. Ferrous and nonferrous tubing having inside diameters at least equal to that of standard pipe size listed above may be substituted for pipe.
	b. 	The scale on the dial of a steam boiler gage shall be graduated to not less than 30 psig nor more than 60 psig. The travel of the pointer from zero to 30 psig pressure shall be at least 3 inches on a compound gage, and effective stops shall be set at the limits of the gage readings on both the pressure and vacuum sides of the gage.
	94.4(3) Water gage glasses.
	a. 	Each steam boiler shall have one or more water gage glasses attached to the water column or boiler by means of valved fittings not less than ½-inch pipe size with the lower fittings provided with a drain valve having an unrestricted drain opening not less than ¼-inch diameter to facilitate cleaning. Gage glass replacement shall be possible under pressure. Water gage glass fittings may be attached directly to a boiler.
	b. 	The lowest visible part of the water gage glass shall be at least 1 inch above the lowest permissible water level recommended by the boiler manufacturer. With the boiler operating at this lowest permissible water level, there shall be no danger of overheating any part of the boiler.
	c. 	Transparent material other than glass may be used for the water gage provided that the material will remain transparent and has proved suitable for the pressure, temperature and corrosive conditions expected in service.
	94.4(4) Water column and water level control pipes.
	a. 	The minimum size of ferrous or nonferrous pipes connecting a water column to a steam boiler shall be 1 inch. No outlet connections, except for damper regulator, feedwater regulator, steam gages or apparatus which does not permit the escape of any steam or water, except for manually operated blowdowns, shall be attached to a water column or the piping connecting a water column to a boiler. If the water column, gage glass, low-water fuel cutoff or other water level control device is connected to the boiler by pipe and fittings, no shutoff valves of any type shall be placed in such pipe, and a cross or equivalent fitting to which a drain valve and piping may be attached shall be placed in the water piping connection at every right angle to facilitate cleaning. The water column drainpipe and valve shall be not less than ¾-inch pipe size.
	b. 	The steam connections to the water column of a horizontal firetube wrought boiler shall be taken from the top of the shell or the upper part of the head, and the water connection shall be taken from a point not above the center line of the shell. For a cast iron boiler, the steam connection to the water column shall be taken from the top of an end section or the top of the steam header, and the water connections shall be made on an end section not less than 6 inches below the bottom connection to the water gage glass.
	94.4(5) Pressure control.
	a. 	In addition to the operating control for normal boiler operation, each individual, automatically fired steam heating boiler shall have a high-limit, pressure-actuated combustion control that will cut off the fuel supply to prevent the pressure from rising over 15 psig. The separate controls may have a common connection to the boiler. Upon replacement of the high-limit, pressure-actuated combustion control, controls with manual reset shall be installed.
	b. 	In a multiple boiler installation where the operating pressure control may be installed in a header or other point common to all boilers and could be isolated from any or all of the boilers, there shall be at least one high-limit, pressure-actuated combustion control mounted on each boiler.
	c. 	No shutoff valve of any type shall be placed in the connection to the high-limit, pressure-actuated control. The control or connections shall contain a siphon or equivalent device that will develop and maintain a water seal that will prevent steam from entering the control. The connections to the boiler shall not be less than ¼-inch standard pipe size, but where steel or wrought-iron pipe or tubing is used, the fittings shall be not less than ½-inch standard pipe size. The minimum size of a siphon, if used, shall be ¼-inch inside diameter. Ferrous and nonferrous tubing having inside diameters at least equal to that of standard pipe size listed above may be substituted for pipe where a manifold is used for a multiple control. The connection to the boiler shall not be less than ¼-inch standard pipe size.
	94.4(6) Automatic low-water fuel cutoff or water-feeding device.
	a. 	Each automatically fired steam or vapor system boiler shall have an automatic low-water fuel cutoff so located as to automatically cut off the fuel supply when the surface of the water falls to the lowest visible part of the water gage glass. If a water-feeding device is installed, it shall be so constructed that the water inlet valve cannot feed water into the boiler through the float chamber and so located as to supply requisite feedwater.
	b. 	A fuel cutoff or water-feeding device may be attached directly to a boiler or in the tapped openings available for attaching a water glass directly to a boiler. Connections in the tapped openings shall be made to the boiler with nonferrous tees or “Y’s” not less than ½-inch pipe size between the boiler and the water glass so that the water glass is attached directly and as closely as possible to the boiler. The run of the tee or “Y” shall take the water glass fittings, and the side outlet or branch of the tee or “Y” shall take the fuel cutoff or water-feeding device. The ends of all nipples shall be reamed to full-size diameter.
	c. 	Fuel cutoffs and water-feeding devices embodying a separate chamber shall have a vertical straightway drainpipe and a blowoff valve not less than ¾-inch pipe size located at the lowest point in the water equalizing pipe connections so that the chamber and the equalizing pipe can be flushed and the device tested.
	94.4(7) Stop valves for single steam heating boilers. When a stop valve is used in the supply pipe connection of a single steam boiler, there shall be one used in the return pipe connection.
	94.4(8) Stop valves for multiple steam heating boilers. A stop valve shall be used in each supply and return pipe connection of two or more boilers connected to a common system.
875—94.5(89) Hot water heating boilers installed before July 1, 1960. Hot water heating boilers installed before July 1, 1960, shall be constructed and installed in accordance with this rule.
	94.5(1) Safety relief valves.
	a. 	Each hot water heating boiler shall have at least one safety relief valve bearing the National Board “HV” stamp of the automatic-resetting type set to relieve at or below the maximum allowable working pressure of the boiler. The safety relief valve shall have pop action when tested by steam. When more than one safety relief valve is used on a hot water heating boiler, the additional valve or valves must bear the National Board “HV” stamp and may be set within a range not to exceed 6 psig above the maximum allowable working pressure of the boiler up to and including 60 psig and 5 percent for those having a maximum allowable working pressure exceeding 60 psig. Safety relief valves shall be so arranged that they cannot be reset to relieve at a higher pressure.
	b. 	No safety relief valve shall be smaller than ¾-inch nor larger than 4½-inch standard pipe size, except those boilers having a heat input not greater than 15,000 Btu’s per hour may be equipped with a safety relief valve of ½-inch standard pipe size bearing the National Board “HV” stamp. The inlet opening shall have an inside diameter equal to or greater than the seat diameter. In no case shall the minimum opening through any part of the valve be less than ½-inch diameter.
	94.5(2) Temperature and pressure gage.
	a. 	Each hot water boiler shall have a temperature and pressure gage properly calibrated to the altitude connected to it or to its flow connection in such a manner that it cannot be shut off from the boiler except by a cock with tee or lever handle placed on the pipe near the gage. The handle of the cock shall be parallel to the pipe in which it is located when the cock is open.
	b. 	The scale on the dial of the temperature and pressure gage shall be graduated approximately to not less than one and one-half nor more than three times the pressure at which the safety relief valve is set. The gage shall be provided with effective stops for the indicating pointer at the zero point and at the maximum pressure point.
	c. 	The temperature gage shall be so located and connected that it shall be easily readable. The thermometer shall be so located that it shall at all times indicate the temperature in degrees Fahrenheit of the water in the boiler at or near the outlet.
	d. 	Piping or tubing for temperature and pressure gage connections shall be of nonferrous metal when smaller than 1-inch pipe size.
	94.5(3) Temperature control.
	a. 	In addition to the operating control used for normal boiler operation, each individual, automatically fired hot water boiler shall have a separate high-limit, temperature-actuated combustion control that will cut off the fuel supply to prevent the temperature of the water from rising over 250° F. Separate controls may have a common connection to the boiler.
	b. 	In a multiple boiler installation where the operating temperature actuated control may be installed in a header or other point common to all boilers and can be isolated from any or all of the boilers, there shall be at least one high-limit, temperature-actuated combustion control mounted on each boiler.
	94.5(4) Low-water fuel cutoff.
	a. 	Each automatically fired hot water heating boiler installed after July 1, 1977, shall have an automatic low-water fuel cutoff which has been designed for hot water service, and it shall be so located as to automatically cut off the fuel supply when the surface of the water falls to the level established.
	b. 	As there is no normal waterline to be maintained in a hot water heating boiler, any location of the low-water fuel cutoff above the lowest safe permissible water level established by the boiler manufacturer is satisfactory.
	c. 	A coil-type boiler or a watertube boiler installed after July 1, 1977, and requiring forced circulation to prevent overheating of the coils or tubes shall have a flow-sensing device installed in the outlet piping in lieu of the low-water fuel cutoff to automatically cut off the fuel supply when the circulating flow is interrupted.
	94.5(5) Stop valves.
	a. 	On single hot water heating boilers, stop valves shall be located at an accessible point in the supply and return pipe connections as near the boiler nozzle as is convenient and practicable to permit draining the boiler without emptying the system.
	b. 	Where two or more boilers are connected in a common system, a stop valve shall be used in each boiler’s supply and return pipe connection.
	94.5(6) Provisions for thermal expansion in hot water heating system.
	a. 	All hot water heating systems incorporating hot water tanks or fluid relief columns shall be so installed as to prevent freezing under normal operating conditions.
	b. 	Systems with open expansion tanks require an indoor overflow from the upper portion of the expansion tank in addition to an open vent. The indoor overflow is to be carried within the building to a suitable plumbing fixture or to the basement.
	c. 	An expansion tank adequate for the volume and capacity of the system shall be installed. If the system is designed for a working pressure of 30 psi or less, the tank shall be suitably designed for a minimum hydrostatic test pressure of 75 psi. Expansion tanks for systems designed to operate above 30 psi shall be constructed in accordance with ASME Code, Section VIII, Division I, in effect when installed. Provisions shall be made for draining the tank without emptying the system, except for prepressurized tanks.
	d. 	The expansion tank capacities for gravity hot water heating systems shall be as follows:

Sq. Ft. of Installed Equivalent	Tank Capacity	
Direct Radiation	Gallons	
Up to 350	18	
Up to 450	21	
Up to 650	24	
Up to 900	30	
Up to 1100	35	
Up to 1400	40	
Up to 1600	2-30	
Up to 1800	2-30	
Up to 2000	2-35	
Up to 2400	2-40	
2400 and up	1 additional gallon per 33 square feet of
additional equivalent direction radiation	
	e. 	The expansion tank capacities for forced hot water heating systems shall be based on an average operating water temperature of 195°F, a fill pressure of 12 psig, and a maximum operating pressure of 30 psig as follows:

System Volume,	Tank Capacity,	
Gallons	Gallons	
100	15	
200	30	
300	45	
400	60	
500	75	
1,000	150	
2,000	300	
In calculating, include the volume of water in boiler, radiation and piping but not the expansion tank.
875—94.6(89) Hot water supply boilers installed before July 1, 1960.
	94.6(1) Scope. This rule establishes minimum requirements for installation, operation, and inspection of hot water supply boilers installed before July 1, 1960, when any of the following limitations are exceeded:
	a. 	Heat input of 200,000 Btu’s per hour.
	b. 	Water temperature of 210°F.
	c. 	A water containing capacity of 120 gallons.
	94.6(2) Safety relief valves. Each hot water supply boiler must have at least one pressure and temperature relief valve bearing the National Board “HV” stamp installed on the hot water outlet line.
	94.6(3) Safety valves and safety relief valves for tanks and heat exchangers.
	a. 	When a hot water supply vessel is heated indirectly by steam in a coil or pipe, the pressure of the steam used shall not exceed the safe working pressure of the tank. A safety relief valve at least 1 inch in diameter shall be installed on the tank and shall be set to relieve at or below the maximum allowable working pressure of the tank.
	b. 	When water over 160° F is circulated through the coils or tubes of a heat exchanger to warm the water for space heating or hot water supply, the heat exchanger shall be equipped with one or more safety relief valves bearing the National Board “HV” stamp of sufficient rated capacity to prevent the heat exchanger pressure from rising more than 10 percent above the maximum allowable working pressure of the vessel. The valves shall be set to relieve at or below the maximum allowable working pressure of the heat exchanger.
	c. 	When water over 160° F is circulated through the coils or tubes of a heat exchanger to generate low-pressure steam, the heat exchanger shall be equipped with one or more safety valves bearing the National Board “HV” stamp of sufficient rated capacity to prevent the heat exchanger pressure from rising more than 5 psig above the maximum allowable working pressure of the vessel. The valves shall be set to relieve at a pressure not to exceed 15 psig.
	94.6(4) Gages. Temperature and pressure gages shall be installed in accordance with 94.5(2).
	94.6(5) Temperature controls. Temperature controls shall be installed in accordance with 94.5(3).
	94.6(6) Stop valves.
	a. 	Stop valves shall be placed in the supply and return pipe connections of a single hot water supply boiler installation to permit draining the boiler without emptying the system.
	b. 	Where two or more boilers are connected in a common system, a stop valve shall be used in each boiler’s supply and return pipe connection.
	94.6(7) Thermal expansion. If a system is equipped with a check valve or pressure-reducing valve in the cold water inlet line, an airtight expansion tank or other suitable air cushion shall be installed. When an expansion tank is provided, it shall be constructed in accordance with the ASME Code, Section VIII, Division 1, in effect when installed, for a maximum allowable working pressure equal to or greater than the water heater. Except for prepressurized tanks, provisions shall be made for draining the tank without emptying the system.
These rules are intended to implement Iowa Code chapter 89.
[Filed 5/6/83, Notice 3/30/83—published 5/25/83, effective 7/1/83]
[Filed emergency 6/13/83—published 7/6/83, effective 7/1/83]
[Filed emergency 9/5/86—published 9/24/86, effective 9/24/86]
[Filed 3/17/89, Notice 9/21/88—published 4/5/89, effective 5/10/89]
[Filed 10/25/91, Notice 7/10/91—published 11/13/91, effective 1/1/92]
[Filed 5/16/96, Notice 11/22/95—published 6/5/96, effective 8/1/96]
[Filed emergency 12/26/97 after Notice 11/19/97—published 1/14/98, effective 1/1/98]
[Filed 3/14/01, Notice 1/24/01—published 4/4/01, effective 5/9/01]
[Filed 2/24/05, Notice 1/19/05—published 3/16/05, effective 4/20/05]
[Filed 7/26/06, Notice 5/10/06—published 8/16/06, effective 9/20/06]
[Filed 11/30/07, Notice 10/24/07—published 12/19/07, effective 1/23/08]