The state of OH is in the process of updating it’s fire code to the 2015 International Fire Code (IFC). In doing so, the state is upgrading its Mechanical Refrigeration requirements and one of the upgrades may have an impact on future Ammonia Refrigeration processes that have over 6.6 pounds (3 kg) of ammonia refrigerant, which would include almost all “industrial applications”. The proposed revised code will require RV discharges to be through an approved treatment system, flare, or diffusion tank unless the fire code official determines, on review of an engineering analysis prepared in accordance with paragraph 104.7.2 of rule 1301:7-7-01 of the administrative Code (see below for 104.7.2), that a fire, health or environmental hazard would not result from atmospheric discharge of ammonia. This wording used to be an “exception” to these discharge requirements and the revised code now makes this the first option in the design basis. “104.7.2 Technical assistance” is a technical opinion and report prepared by a qualified engineer, specialist, laboratory or fire safety specialty organization acceptable to the fire code official and will have analyzed the properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon, to recommend necessary changes. If the fire code official determines, on a review of this engineering analysis that a fire, health or environmental hazard would not result from the atmospheric discharge of ammonia then and only then will the facility be permitted to discharge their RV’s directly to the atmosphere. So the RVs can go to atmosphere, but the facility will have to have a technical opinion and report prepared by a qualified engineer to justify it AND THEN the fire code official will have to “sign-off” on the design basis. Here is what the proposed code looks like:
3606.12.5 Ammonia refrigerant. Systems containing more than 6.6 pounds (3 kg) of ammonia refrigerant shall discharge vapor to the atmosphere in accordance with one of the following methods:
- Directly to atmosphere where the fire code official determines, on review of an engineering analysis prepared in accordance with paragraph (D)(7)(b)(104.7.2) of rule 1301:7-7-01 of the administrative Code (see below for 104.7.2), that a fire, health or environmental hazard would not result from atmospheric discharge of ammonia.
- Through an approved treatment system in accordance with paragraph (F)(12)(f)(606.12.6) of this rule.
- Through a flaring system in accordance with paragraph (F)(12)(g)(606.12.7) of this rule.
- Through an approved ammonia diffusion system in accordance with paragraph (F)(12)(h)(606.12.8) of this rule.
- By other approved means.
Exception: Ammonia/water absorption systems containing less than 22 pounds (10 kg) of ammonia and for which the ammonia circuit is located entirely outdoors.
104.7.2 Technical assistance. To determine the acceptability of technologies, processes, products, facilities, materials and uses attending the design, operation or use of a building or premises subject to inspection by the fire code official, the fire code official is authorized to require the owner or owner’s authorized agent to provide, without charge to the jurisdiction, a technical opinion and report. The opinion and report shall be prepared by a qualified engineer, specialist, laboratory or fire safety specialty organization acceptable to the fire code official and shall analyze the fire safety properties of the design, operation or use of the building or premises and the facilities and appurtenances situated thereon, to recommend necessary changes.
606.12.6 Treatment systems. Treatment systems shall be designed to reduce the allowable discharge concentration of the refrigerant gas to not more than 50 percent of the IDLH at the point of exhaust. Treatment systems shall be in accordance with rule 1301:7-7-60 of the Administrative Code.
606.12.7 Flaring systems. Flaring systems for incineration of flammable refrigerants shall be designed to incinerate the entire discharge. The products of refrigerant incineration shall not pose health or environmental hazards. Incineration shall be automatic upon initiation of discharge, shall be designed to prevent blowback and shall not expose structures or materials to threat of fire. Standby fuel, such as LP gas, and standby power shall have the capacity to operate for one and one-half the required time for complete incineration of refrigerant in the system. Standby electrical power, where required to complete the incineration process, shall be in accordance with paragraph (D)(604) of this rule. (the emergency power is a new requirement)
606.12.8 Ammonia diffusion systems. Ammonia diffusion systems shall include a tank containing 1 gallon of water for each pound of ammonia (48.3 L of water for each 1 kg of ammonia) that will be released in 1 hour from the largest relief device connected to the discharge pipe. The water shall be prevented from freezing. The discharge pipe from the pressure relief device shall distribute ammonia in the bottom of the tank, but no lower than 33 feet (10 058 mm) below the maximum liquid level. The tank shall contain the volume of water and ammonia without overflowing.