Chapter 11.1 NFPA 96 2014
Example: You survey a Kitchen Hood system and discover they have mesh filters Solution: You quote “approved” filters and reference that their old filters under NFPA 96, Section 6.1.3 (Mesh filters shall not be used). This is also referenced under Annex A – A.220.127.116.11 The following are some of the more common things you will come across in the kitchen hood exhaust system.
However, you should have a copy of NFPA 96 and be familiar with all aspects of the pamphlet. I. 11.3 Inspection of Exhaust Systems.
The entire exhaust system shall be inspected by a properly trained, qualified, and certified company or person(s) acceptable to the authority having jurisdiction in accordance with Table 11.3 II. 11.3 Exhaust System Inspection Schedule Frequency Systems serving solid fuel cooking operations
Monthly Systems serving high-volume cooking operations Quarterly Such as 24-hour cooking, charbroiling, or wok cooking Systems serving moderate-volume cooking operations
Semiannually Systems serving low-volume cooking operations such Annually As churches, day camps, seasonal businesses or senior Centers Important: NFPA, pamphlet 96 references this schedule as a MINIMUM safety Requirement for cooking equipment. II.
11.4 Cleaning of Exhaust Systems. 11.4.1 Upon inspection, if found to be contaminated with deposits from grease-laden vapors, the entire exhaust system shall be cleaned by a properly trained, qualified, and certified company or person(s) acceptable to the authority having jurisdiction in accordance with Section 11.3 At least, cleaning should be done in accordance with NFPA 96, 11.4.2 through 11.4.14.
11.4.2 Hoods, grease, removal devices, fans, ducts and other appurtenances shall be cleaned to bare metal prior to surfaces becoming heavily contaminated with grease or oily sludge.
11.4.3 At the start of the cleaning process, electrical switches that could be activated accidentally shall be locked out.
11.4.4 Components of the fire suppression system shall not be rendered inoperable during the cleaning process.
11.4.5 Fire-extinguishing systems shall not be rendered inoperable during the cleaning process where serviced by properly trained and qualified persons in accordance with Section 11.3.
11.4.6 Flammable solvents or other flammable cleaning acids shall not be used.
11.4.7 Cleaning chemicals shall not be applied on fusible links or other detection devices of the automatic extinguishing system.
11.4.8 After the exhaust system is cleaned to the bare metal, it shall not be coated with powder or other substance.
11.4.9 All access panels (doors) and cover plates shall be replaced.
11.4.10 Dampers and diff-user shall be positioned for proper airflow.
11.4.11 When cleaning rules are completed, all electrical switches and system components shall be returned to an operable state.
11.4.12 When a vent cleaning service is used, a certificate showing date of inspection or cleaning shall be maintained on the premises.
11.4.13 After cleaning is completed, the vent cleaning contractor shall place or display within the kitchen area a label indicating the date cleaned and the name of the servicing company, and areas not cleaned.
11.4.14 Where required, certificates of inspection and cleaning shall be submitted to the authority having jurisdiction. III. Exhaust Fans In order to thoroughly and properly clean an up blast exhaust fan, you must be able to lift the fan off the housing. In order to do this, the fan needs to be hinged and have enough waterproof flexible cable. If fans are not hinged or need proper wiring, refer to code 8.1.1
18.104.22.168 Approved up-blast fans with motors surrounded by the air stream shall be hinged , supplied with flexible weatherproof electrical cable and service hold open retainers, and listed for this use. IV. Spark Arrester’s When cleaning a solid fuel system duct, it is important that a spark arrestor be installed, due to the increase passage of embers through duct system. Refer to code 3.3.43.
3.3.43 Spark Arrester. A device or method that minimizes the passage of airborne sparks and embers into a plenum, duct and flue. V. Access Panels To properly and thoroughly clean an exhaust duct system, you must have proper access both vertically and horizontally and at the changes of duct direction. Refer to codes 7.3.1 through 22.214.171.124
Access panels need to be approved and installed in accordance with NFPA 96. Refer to code 7.5.2. VI. Duct Construction Air duct is not allowed for kitchen hood exhaust systems. Refer to code 7.5.1
6.5.1 Materials. Ducts shall be constructed of and supported by carbon steel not less than 1.37 mm (0.054 in) (No. 16 MSG) in thickness or stainless Steel not less than 1.09 mm (0.043 in.) (No. 18 MSG) in thickness. Ducts are to have a continuous weld. In older systems it is common to see separated welds in the ducts. This becomes a fire hazard due to grease leakage. Refer to code 126.96.36.199
188.8.131.52 All seams, joints, penetrations, and duct to hood collar connections shall have a liquid tight continuous external weld. Be familiar with this pamphlet and know the codes. This will help set you apart from the competition.