Friday, July 22, 2016

CO2 Safety

This presentation will cover certain physical properties of CO2, aspects of CO2 in a Speedway store, some model building code items & NJ field inspection nuances that may apply in other states too. CO2 gas in a beverage system is heavier than air therefore leaking CO2 gas can accumulate at the floor level in an improperly ventilated or unventilated room. CO2 gas is colorless & odorless. Exposure to high levels may cause unconsciousness or death within minutes. Per the equipment schedule on some Speedway remodels a 20” diameter x 60” high pressurized tank is provided that construction coordinates for install. This tank size can hold approximately 300 lbs. of CO2 @ 125 psig. If the pressure inside the tank exceeds 300 psig for any reason a primary relief valve on the top of the tank will vent the excess pressure. CO2 can only exist as a liquid while under pressure. If pressure is lost, liquid CO2 turns to dry ice. Dry Ice can start to form any time pressure drops below 60 psig. Speedway vendor, Nuco2, notes that some exterior frost can collect on the tank during normal & high demand periods. Beverage Grade liquid CO2 mixes with filtered water inside of a “carbonator” (typically located below the counter under the soda fountain machine) to produce carbonated water that is then mixed with syrup to make soft drinks. The following are some new requirements that were approved for addition into the 2015 International Fire Code for CO2 beverage systems: *Areas where a leak of CO2 could collect will be required to be provided with either ventilation OR an emergency alarm system consisting of CO2 detectors and local alarm. If ventilation is the remedy in the drawings: *Exhaust must be taken from a point within 12 inches of the floor. Typically the remodel designs use an emergency alarm system which should include: 1. Continuous gas detection sensor provided to monitor areas where carbon dioxide can accumulate. 2. The threshold for activation of a detector is not to exceed 5,000 parts per million. 3. A local alarm device (e.g. a strobe/flashing light) shall also be installed at an approved location. On a sidebar, NFPA 55 chapter 13 calls for a warning sign to be posted at the entrance to the room or confined area where the container is located; The warning sign shall say: CAUTION — CARBON DIOXIDE GAS. Ventilate the area before entering. A high carbon dioxide (CO2) gas concentration in this area can cause suffocation. In NJ, fire officials finding installations that have not been approved by the construction official can issue a violation notice and notify the construction official. When a business owner opts to install a local detection system, it may be approved by the fire subcode official. Also in NJ, the pressurized tank is regulated by the Department of Labor, Boiler and Pressure Vessel Bureau. An inspection sticker has to be issued by the NJ DOL for the use of the pressure vessel. The Bureau will perform a site inspection every three (3) years. A NJ construction final approval may not be issued for these installations until the NJ DOL registration has been verified.