FREQUENTLY ASKED QUESTIONS



Why can't my employees clean the hoods?

NFPA 96 states, "The entire exhaust system shall be cleaned by a properly trained, qualified, and certified company or persons." Work of this nature takes special tools, equipment and expertise to properly and thoroughly clean the exhaust systems.



What should I look for when hiring a company?

You should look at training, certification, reputation and years in business. National Guardian has been in business for over 38 years and is fully insured and licensed with bonded service technicians. When contracting for cleaning services, it is important to ensure you get a complete cleaning of your entire system. Some contractors offer a "hood cleaning" service, which does not include the ductwork or rooftop fan. While such services may keep the interior of the kitchen looking sharp, they do little to secure fire safety and reduce health threats. Only a complete cleaning of the system from the hood in the kitchen, to the fan on the roof, will reduce the risk of kitchen fires and ensure compliance with fire regulations.



What do you clean?

We clean the entire system starting from the exhaust fan housing, down the flue, and into the plenum area, cleaning the system to bare metal per NFPA 96 standards. We clean the linkage for the fire suppression system, the filters, grease gutters, and clean the hood inside and out.



Why is cleaning the entire system important?

The statistics from the NFPA indicate that in an average year approximately 5,900 restaurant fires are reported with total property losses reaching $80 million. These fires originated in the cooking area, which then explode into the exhaust system and onto the roof where the fire can quickly spread. Grease fires burn very hot, approximately 1400 degrees Fahrenheit. At this temperature, fire spreads very rapidly. Having National Guardian maintain a grease-free and fire-safe kitchen exhaust system will help protect your restaurant from fire hazards.


  • Reduced risk of kitchen fires.

  • Enhanced working environment for kitchen staff.

  • Improved ventilation for smoke and odor removal.

  • Lower insurance premiums offered by some insurance companies.

  • Compliance with local and national fire and health codes.



How often does my system need to be cleaned?

Frequency of cleaning depends on many variables; cooking source, the type of cooking you do, and how often the systems are used. We will schedule your cleaning based on your individual restaurant needs. Restaurant kitchen exhaust systems, according to NFPA Standard 96 should be inspected by a properly trained, qualified, and certified company or individual. NFPA 96 has established minimum frequencies for the inspection of systems but based on the type or volume of cooking the inspections may be required more often. While a low-volume cooking establishment shall be inspected annually, high-volume operations such as fast food, charbroiling, or solid fuel cooking operations may require monthly or even weekly inspections. If the system is found to be contaminated, the entire exhaust system shall be cleaned. During peak seasons the frequency of inspections and cleaning should be increased.



What is Fire Code NFPA 96?

Standard for ventilation control and fire protection of commercial cooking operations, NFPA 96 details that the minimum fire safety requirements (preventative and operative) related to the: design, installation, operation, inspection and maintenance of all public and private cooking operations, excluding single-family residential usage. These requirements include, but are not limited to all manner of cooking equipment, exhaust hoods, grease removal devices, exhaust ductwork, exhaust fans, dampers, fire extinguishing equipment, and all other auxiliary or ancillary components or systems that are involved in the capture, containment and control of grease laden cooking effluent. The provisions of this standard are considered necessary to provide a reasonable level of protection from loss of life and property from fire and explosion. The standard is intended to be applied as a united whole, it cannot provide safe design and operation if parts of it are not enforced or are arbitrarily deleted in any applications. The authorities having jurisdiction shall determine compliance with this standard and authorize equivalent derivations from it in all applications.