Kitchen suppression systems are designed, tested, and approved to provide fire protection for commercial kitchen cooking appliances, hoods, and ducts. The suppression systems consist of an agent storage tank, manual release station, an automatic releasing mechanism, and supply piping that directs the agent to nozzles strategically positioned at heat sources in the kitchen.
NFPA 17 requires that every 12 years the agent-holding tank, whether it is a pressurized or non-pressurized system tank, must be pulled out of service to be tested.
For all systems, the agent storage tank must be pressure tested to ensure the integrity of the cylinder. There are many types and manufactures of kitchen commercial wet chemical systems, each one has different test pressures for the cylinder, which are set by the manufacturer. Once filled with water, and sometimes oil, the cylinder is capped off, then pressurized to the manufacture test pressure and held at that pressure for no less than 1 minute. These systems are often tested to almost two times the service pressure.
On a non-pressurized system, there is a cartridge that pushes the agent out of the cylinder. This cartridge is replaced every 12 years. In some instances, these systems can have a burst disc that would need to be replaced before the 12-year hydrostatic test is scheduled.
Pressurized systems have valve stems, O-rings, and pins that need to be replaced. This is called a rebuild kit.
Once all of the cylinders are tested, dried, and documented they get filled back up with the proper wet chemical agent and put back into service if there is not any issues with the test pressures. All systems, both pressurized and non-pressurized, get new agent during a 12-year hydrostatic test. For certain suppression systems, hoses will need to be replaced at the 12-year hydrostatic test.
Your fire safety system depends on the accurate detection of smoke by your smoke detectors. In order to ensure your smoke detectors are working properly, and able to protect your people and assets, you must have sensitivity testing completed on a regular basis.
Smoke detectors are designed to function effectively within a specific range of sensitivity to smoke. This range is set by the manufacturer and the devices are required by NFPA to be tested regularly to ensure they remain within it. If a smoke detector is not as sensitive as it should be, then it may not react as quickly as it should to a fire. However, if the smoke detector is too sensitive, then you could have recurring nuisance alarms.
There are several options for performing sensitivity tests on smoke detectors. Sensitivity tests can be conducted by a recognized, calibrated test method with smoke or listed aerosol, or with equipment specifically designed for calibrating sensitivity in smoke detectors. There are listed control equipment arranged to perform sensitivity ranges and calibrated sensitivity test instruments designed by the smoke detector manufacturers. You can also use a combination smoke detector/control unit where the detector causes a signal at the control panel unit when its sensitivity is outside its listed sensitivity ranges.
During sensitivity testing, if a detector fails, it will need to be cleaned and retested. Cleaning smoke detectors should be left to your Life Safety Partner, as they will clean the smoke detector screen and chamber using a non-electrostatic vacuum specifically designed to prevent damage to the detector. After cleaning, the detector will be retested, if it fails again then it needs to be removed from service.
Sensitivity testing must be completed within one year of installation and every other year after that. After the second test, if the detector is within its listed sensitivity range for two consecutive tests, then the next sensitivity test is required in five years.
According to the National Fire Protection Association (NFPA), more than half of the 8,160 structure fires involving commercial cooking equipment or ventilation components that occur annually begin in kitchens or cooking areas. Between 2004 and 2008, these cooking fires caused three deaths, 100 injuries, and $229 million in director property damage each year.
A kitchen hood is important fire protection at it eliminates air contaminants and toxic chemicals from the air, which are released when cooking. The filters in the kitchen hood capture grease and debris in these fumes and prevents them from entering your exhaust system.
Kitchen hood grease filters are an important fire prevention device. With grease or debris in your exhaust ducts, a fire could occur within the hood system. Duct fires can be intense, difficult to extinguish, and are susceptible to re-ignition.
No cook likes to clean the grease filters, however, regular cleaning of your grease filters is critical to maintaining proper function. Let your kitchen staff focus on their real job functions and remove this risk of worker compensation claims by collaborating with a knowledgeable partner to clean your filters. Having your Life Safety Partner perform this service will save you money while also keeping your employees safe, and your kitchen in compliance.
A filter exchange program can be a real benefit to any food service company or restaurant. At the intervals required for your kitchen, based on cooking methods, appliances, and volume of operation, your filters will be scheduled for automatic replacement.
Not only are the dirty filters removed and replaced with clean filters, but also the dirty filters are taken off-site to be cleaned. By not cleaning the grease filters at your restaurant you can reduce the amount of grease going down your drain by up to 70%, and the grease will be disposed of in an environmentally friendly manner. This offsite cleaning will save you money by reducing chemical costs, water usage, and the amount of grease in your traps.
Kitchen Hood systems are one of the most widely used fire protection systems given the fire source and fuel load. Kitchen Hood systems include the hood, exhaust, and ducting systems over your cooking appliances. This system vents airborne grease, combustion products, fumes, smoke, odors, heat, and steam.
These systems are customized for the kitchen layout as well as each appliance. Kitchen Hood systems require regular maintenance and inspections as grease build-up, damage to the hood, or moved appliances can cause the Hood system, along with any interconnected fire suppression system, not to function properly. You can read A1’s blog for more information on the kitchen hood suppression system.
The required schedule for cleaning a Hood system varies based on the type of cooking appliances, methods, and amount of use. According to NFPA 96, general guidelines for cleaning a Kitchen Hood system are as follows:
- Kitchens with solid fuel such as wood or charcoal must have the kitchen hood system cleaned every month.
- Kitchens with a high volume, 24 hour operations, charbroiling, or wok cooking must have the kitchen hood system cleaned every 3 months.
- Kitchens with moderate volume operations must have the kitchen hood system cleaned every 6 months.
- Kitchens with low volume operations, such as churches, day camps, seasonal business, or senior centers, must have their kitchen hood system cleaned once a year.
Because the Kitchen Hood system is cleaned in areas you will not be able to see on a daily basis, such as inside the ducts and vents, it is important that you are provided with before and after pictures of your system such as the ones shown here. You also want to be sure that all areas of your Kitchen Hood system are being cleaned – this includes fans, vertical duct, horizontal duct, plenum, inside and outside of the hood system and cleaning inside access panels.
Most of these areas are not ones that are not regularly visible. However, grease buildups occur throughout the system and it is critical that the full hood system is cleaned to bare metal in order to ensure proper function and continued safety.
Corrosion is a problem that must be addressed in both dry pipe and wet pipe sprinkler systems. In this article, we will discuss pipe corrosion in wet sprinkler systems and methods of preventing the corrosion.
The water that fills wet sprinkler pipes contains approximately 10 parts per million (ppm) of dissolved oxygen. All wet systems experience initial corrosion because of this dissolved oxygen. However, this corrosion is self-limiting as some of that dissolved oxygen will be consumed until the system is refilled with fresh, oxygenated water.
The primary catalyst of pipe corrosion in a wet system is air that has been trapped in air pockets of the pipes. These air pockets exist frequently within wet system pipes at high points of the piping. These trapped air pockets contain 20.9% oxygen, which can fully sustain electrochemical corrosion. As a result, pinhole leaks eventually develop at the location of the air pockets. These leaks have costly results including property and equipment damage, ongoing repairs to pipes or full system replacement, sprinkler head blockages, and an inoperable fire protection system that puts your people and assets at risk.
In order to prevent pinhole leaks, there must be less than 2% oxygen in the trapped space (reduced from the 20.9% that would typically be present). There are several preventative actions that can be taken: wet air vents, auto inert with nitrogen, and remove oxygen from the water. While each action can be taken individually, the best results occur when they are combined.
Wet Air Vents
Installing wet air vents is the most basic step you can take to reduce oxygen corrosion in your wet sprinkler pipes. Your Life Safety Partner will install the wet air vents at high points and other potential areas where air can be trapped, in order to provide a vent to remove the air. There are two types of wet air vents, single and dual. Both types remove the oxygen from the pipe, venting it outside the sprinkler pipe. A single vent removes the air and closes the valve when water reaches it, this water then drains back into the sprinkler pipe. The single vent will discharge any overflow so it should not be used in areas that are water sensitive. A dual vent will not discharge water so it is safe to install in water sensitive areas. As the pressure from the sprinkler pipe drops, any collected water in the air vents will automatically drain back to the sprinkler pipe through the secondary valve. The dual valve also creates redundancy, eliminating any failure concerns.
Auto Inert with Nitrogen
Filling the sprinkler pipes with high purity nitrogen gas prior to charging the system with water can ensure that corrosion in all trapped air locations is slowed. To do this to a wet sprinkler pipe system, you must first drain the fire protection system of all water and install an auto inert system. The fire sprinkler system is then filled with 98% pure nitrogen through the inert system. By displacing the trapped air with high-purity nitrogen, you minimize the source of oxygen to sustain electrochemical corrosion and corrosion cells have less chance of propagating.
You can use this technique in place of wet air vents, as installation of wet air vents may not always be possible due to lack of headroom or varying elevations, which make identification of trapped air pockets challenging or impossible. However, the best results for slowing corrosion occur when you combine the two solutions.
Removing Oxygen from a Wet Pipe Sprinkler System
Removing oxygen from a wet pipe sprinkler system is the best option to slow, or eliminate, internal wet system corrosion. In addition to the wet air vents, this method removes the oxygen from the trapped air pockets and reduces the dissolved oxygen in water to 1.0 ppm or less.
First, the wet pipe system is pre-purged with nitrogen. This changes the pockets of trapped air to pockets of trapped nitrogen gas, which does not act as a catalyst for corrosion like oxygen does. The sprinkler pipe is filled with deoxygenated water, 1.0 ppm or less of dissolved oxygen. This deoxygenated water, which is below the threshold of oxygen known to cause corrosion, stays in constant contact with the sprinkler piping. There is now not enough oxygen in the water to dissipate into the trapped nitrogen gas pockets, which protects the areas of pipe that would have corroded under normal circumstances.
Understanding the correct cause can help you to slow or stop dry sprinkler pipe corrosion.
Microbiologically influenced corrosion (MIC) was once thought to be the primary threat to sprinkler pipe longevity. However, further research has found that oxygen is the primary factory in sprinkler pipe corrosion for both wet and dry pipe systems. In this article, we will discuss how corrosion occurs in a dry sprinkler system and the options for preventing or slowing this corrosion in order to maintain your system and extend the life of your sprinkler piping.
The corrosion triangle illustrates the three factors necessary for corrosion to take place: an unprotected metal, electrochemical potential in the form of oxygen, and electrolyte in the form of moisture. When all three factors are present, there interaction results in corrosion of the unprotected metal. To prevent corrosion, you must remove one factor in the corrosion triangle.
Removing the Unprotected Metal from the Equation
Galvanized steel prevents corrosion by having a protective surface between the metal and the water or air; Black steel pipe has little to no protective coating. However, both galvanized steel and black steel pipes present opportunities for corrosion – an issue we will go into further in a future blog.
Removing Water from the Equation
The definition of a dry sprinkler pipe system says that the sprinkler pipes are dry – without water. And this is true, the purpose of a dry sprinkler system is to provide piping without water in sensitive areas, such as areas where the water in sprinkler pipes would freeze or locations where any water leakage could cause serious damage. (Although, if your sprinkler system is located in an area where any water can cause serious damage to the facility or equipment, it is best to look at other fire suppression options such as aerosol based or clean agents.)
However, dry sprinkler pipes will still collect trace amounts of water due to hydrotesting, flow testing, and condensation. Even when you properly drain the system on a regular basis (read more on how to drain your dry system pipes here – drip drum blog), the water is present and can react with the pipe and oxygen to create corrosion. The remaining option is to remove the oxygen from the dry pipe system in order to prevent corrosion.
Removing Oxygen from the Equation
Dry sprinkler and pre-action system pipes are pressurized with air until the system is alerted that a fire is occurring, at which time the sprinklers activate releasing the air from the system and filling the pipes with water. Instead of pressurizing these pipes with air, however, you can pressurize them with nitrogen, which does not react with the water or pipes to create corrosion.
Ongoing, long-term exposure tests have been conducted, and have shown that nitrogen filled sprinkler pipes slow or stop corrosion and extend the life of the sprinkler pipes significantly. This preventative measure for your dry sprinkler system can save you money in costly repairs due to corrosion including property and equipment damage, ongoing repairs to pipes or full system replacement, sprinkler head blockages, and an inoperable fire protection system that puts your people and assets at risk.
Nitrogen arrests electrochemical, galvanic and MIC corrosion. The nitrogen also prevents ice plugs by ensuring a -40F to -70F dew point within the sprinkler system. As high purity nitrogen enters the sprinkler piping, corrosive oxygen is displaced – preventing corrosion, slowing corrosion that may already have occurred, and maintaining your sprinkler system for a longer life span.
What are Drum Drips?
Drum drips are drains on dry sprinkler systems, which are used to empty the dry sprinkler pipe of any water that has collected due to condensation or water draining within the system. Since dry pipe systems are utilized in areas where water may freeze, it is important to regularly remove any condensed water to prevent freezing and damage to the pipes.
Drum drips can also be called auxiliary drains, drip legs, and condensate drains. No matter what they are called, a drum drip consists of two, 1-inch valves with a short section of two-inch pipe between them. These are normally located at the lower points of the system or where piping elevation changes may occur.
Locating and Labeling Drum Drips
Systems may have multiple drum drips and it is important that each be drained on a regular basis to prevent costly damage from freezing water. NFPA standards require that drum drips within buildings be identified so that they are easier to maintain. You must also have an informational sign at the system’s control riser that includes the location of all drum drips.
When to Perform Drum Drip Maintenance
All drum drips should be operated weekly during the fall and winter months, even if no water is found on a regular basis. When preparing for cold weather, you should operate the drum drips daily and may decrease the operation based on the amount of water discharged.
After a dry sprinkler system operation, you should perform drum drip maintenance on a daily basis until several days pass with no discharge of water from the drain valve. At that time, you can decrease the frequency to weekly or longer intervals depending on the volume of water discharged.
In many cases, frequency of drum drip maintenance can decrease if the system is shown to be dry.
How to Perform Drum Drip Maintenance
- Locate all drum drips throughout the property.
- If a quick opening device is installed, temporarily remove it from service.
- At the drum drip, ensure both valves on the drum drip are closed.
- To catch any water that may discharge from the drum drip, place a container underneath the bottom valve. For interior locations, remove the plug from the bottom valve. (Exterior locations may not have a plug.)
- Slowly open the top valve to full open position and maintain this position for 10 seconds.
- Close the top valve. **You should never open both the top and bottom valve at the same time as this may activate your system.**
- Slowly open the bottom valve to discharge any water. If you cannot see the discharge point, allow water to drain for 10 seconds.
- Close the bottom valve.
- If water discharged when you opened the bottom valve, repeat steps 5 through 8 until no water appears when you open the bottom valve. This will ensure you have removed all water from the system.
- When the system has been completely drained, meaning no water appears when the bottom valve is opened, close the bottom valve. Then slowly open the top valve and, if applicable, replace the plug. This will return the drum drip to service.
- If you removed a quick opening device from service before beginning drum drip maintenance, re-install it at this time.
If your drum drip discharges to a location you cannot see, you can use a second person to watch the drain and notify you when there is no more water draining from the system. Another option to identify when all water has been removed from the system is to place a bucket under the drain and empty the bucket after each discharge.
If you are discharging water without using a bucket to collect it, be sure the water will not cause a safety hazard in traffic areas, or damage any surrounding areas or equipment.
Need more help? Check out A1’s video on how to perform drum drip maintenance.
The importance of pressure gauges on a fire sprinkler system can sometimes be overlooked. It is a common misconception that if a pressure gauge is registering pressure then it is operating properly. We must first take a look at what these gauges are and how they are used in order to completely understand their importance as a part of your sprinkler system.
Types of Pressure Gauges: Dry and Liquid Filled
Pressure gauges for a fire sprinkler system come in two basic types: dry and liquid filled. The dry gauge is most common; it consists of a numbered dial with an indicating needle that is attached to a spring loaded mechanism. This spring is compressed by pressure from the system, causing the needle to rise in relation to the amount of pressure. Liquid filled gauges operate under the same principle but are completely filled with liquid, usually glycerin. The liquid does a couple things, it lubricates and protects components in the gauge from wear and corrosion, while at the same time it dampens vibration and small spikes or jumps of the needle as pressures change. This creates a more sensitive precise gauge. For that reason, these gauges, which are higher in price, are usually used on testing or other more demanding applications.
Selecting the Correct Gauge
Gauges can be manufactured for a specific application, such as fire pump readings and high pressure systems, or for a specific pressure type such as water pressure, air pressure, or a combination. Choosing the proper gauge for the application should be done by a trained Life Safety professional, as not just any gauge may be installed. NFPA 13 requires the gauge be approved for the application as well as have UL and FM approval. Your Life Safety Partner will also have the expertise needed to determine gauge location and correct installation procedures. Gauges are typically installed on ¼”, 3-way valves to allow easy replacement without taking the system out of service since fire sprinkler systems should always be functioning.
Gauge use in a Fire Sprinkler System
Fire sprinkler systems are always on, active, and supplied by an automatic water supply. Gauges help us ensure that the system is active, in service, and proper water supply and pressure is available. Located at various points in the system, they give us an indication of what the system status is and if anything has changed that may affect performance. Water pressure gauges at the control risers indicate the system is active and supplied by water pressure. This “resting active” pressure is known as static pressure. When the main drain on the system is opened completely, a water flowing pressure reading can be taken here which is known as a residual pressure. Your Life Safety Partner will track these readings during annual inspections, a change in this residual pressure can give warning to changes in the water supply or supply piping system. Gauges monitoring air pressure on dry systems are important for setting the correct air to water pressures on dry valves and recording trip pressures. A system air pressure that is too high could result in delayed trip times, too little could cause false trips. Gauges are used too monitor pressures on standpipes, fire pump performance, and many other functions.
Inspection and Maintenance
As with any other critical component of a sprinkler system, gauges must be tested, inspected and maintained. Gauges are used in almost every stage of system testing. Quarterly, semi-annual and annual inspections all include testing that involves gauges. NFPA requires a monthly visual inspection of gauges noting any damage, leakage, or unusual readings. The date of the gauge should also be noted in inspections, as NFPA requires all gauges to be tested or replaced every 5 years. When gauges are tested, they must fall within a +/- 3% accuracy range or they have to be re-calibrated. Because the cost of new gauges is relatively low, it is common to have the gauges replaced rather than paying for the testing and re-calibrating.
A1 is a leading expert on the latest technology in life safety. To find out more information or to ask a question, click here or call us at 1-800-859-6198.
NFPA 25, Standard for the inspection, testing, and maintenance of water-based fire protection systems, requires that a standpipe system be visually inspected on a regular basis.
If your building or facility has multiple levels or a large area such as an enclosed shopping mall then you may have a standpipe system. This water based fire system is an integral part of your building’s fire and safety design as it can supply the building’s sprinkler system and allows firefighters to hook up fire hoses directly on the level where a fire is occurring.
There are different types of standpipes, some may have water in them while others are dry and need to be hooked to a water supply for use; some standpipes have enough pressure from the water supply to work on their own, while others need the help of a fire department pumper truck.
Pictured above is one example of a stand pipe with a 2 ½” hose vale. These vales should be checked weekly for damage, leaks, or missing caps.
What you need to do:
No matter what type you have, it is important to inspect your standpipe weekly for:
- Signs of physical damage or leakage.
- Make sure all control valves are in place.
- Check for dry rot on the hose and cap gaskets.
- Check for proper labels on equipment.
- Make sure equipment is accessible – not blocked by boxes or other items.
- Gauges on dry, pre-action, and deluge valves for standpipes should be inspected for normal air and water pressure; automatic standpipes can be inspected monthly.
The most common problems found with standpipes are related to housekeeping – keep your standpipes in good working order by keeping the area around the standpipe and valves cleaned and painted in order to prevent corrosion. Standpipes are commonly in need of maintenance for leaking valves, missing caps or handles, and damaged devices – all of which you will be able to see on your weekly checks so it can be fixed right away, before the problem escalates!
Your weekly checks should find any emergency maintenance problems, your required semi-annual and annual inspections will test the system thoroughly for issues you would not be able to see in your weekly checks. At the semi-annual inspection, your alarm devices, valve supervisory devices, and supervisory signal devices will be tested. In addition to these, the annual inspection will test the hose nozzles, hose storage devices and main drain.
Every 3 to 5 years, inspections will include a pressure test on hoses; testing of control valves, pressure-reducing valves and system flow; dry standpipe system piping, hydrostatic test; and a full flow test. Your inspector will lubricate and operate all valves and hose connections to ensure everything is working properly and they will remove the hoses from racks to reload them in order to keep them in good working order.
Read more about Standpipes, the different types, required inspections, and more in our Standpipe Systems Ebook. A1 is a leading expert on the latest technology in life safety. To find out more information or to ask a question, click here or call us at 1-800-859-6198.
Regular maintenance and testing can only help your facility. As they say, “don’t judge a book by its cover.” Your fire protection equipment may appear to function on the surface, but failing to check the working order will leave you in a world of hurt. Systems will break down unexpectedly, and you may even shorten the life of your systems altogether. Here are 6 elements to building safety that are often neglected.
- Fire Sprinklers: On the surface, your system may seem to be in full working order. Unfortunately, most of the serious threats to a sprinkler system happen within. Pipe corrosion and valve trouble are just two examples. Follow the NFPA guidelines for regular sprinkler inspection and maintenance for your facility.
- Blocked Equipment: Any blocked safety equipment is not compliant and is a hazard. Check your sprinklers, exit signs, emergency exits and any other safety system that could be obstructed.
- Old Batteries and Lights: Exit signs use light bulbs and back up batteries to function. Neglected signs can have old, leaky batteries or light bulb outages. These issues are not detectable without opening the apparatus. Check each exit light according to NFPA standards to prevent deficiencies. Another option is to install photoluminescent lights. You can read about them here.
- Smoke Detectors: Smoke detector sensitivity should be tested regularly as well. Detectors that are too sensitive will trigger nuisance alarms. Conversely, detectors that are not sensitive enough may not detect the presence of smoke and will put occupants in danger.
- Fire Doors: NFPA has recently placed more stringent requirements on fire doors. Fire doors must be evaluated to make sure they’ll close and block fire when they need to.
- Emergency Plans: Besides your safety systems, you need an emergency action plan. Who uses the extinguishers? How will people get out? These questions are important for everyone’s safety. Changes in building layouts, or operations can make a plan outdated. If you already have an emergency plan, review it regularly. Most importantly, keep occupants informed. Hold a training, distribute instructions, or have signs so everyone knows how to get out.
Facilities management is an incredibly involved process. Something always needs to be fixed. Taking care of these 6 safety items would keep you ahead of the curve with less risk.