Regulations and Standards for Domestic and Commercial Gas Plumbing
Today, due to the increase in construction and the many buildings present, the use of building plumbing has also increased significantly. On the other hand, traditional plumbing systems are never sufficient to meet the needs of this era. Pipes are used for various locations, including commercial or residential complexes. Gas plumbing is also one of the very sensitive and important operations in the construction process. The reason for this importance is the flammability of gas and the associated risks. In urban gas plumbing, polyethylene pipes are usually used. However, metal plumbing has many disadvantages, including corrosion and rust, so these pipes must also be insulated. Join us to learn more about the regulations and standards for domestic and commercial gas plumbing.
Regulations and Standards for Domestic and Commercial Gas Plumbing
There are regulations and rules for supplying gas to public and private buildings that must be strictly observed. The designer is obligated to ensure complete and sufficient safety for building users against risks arising from natural gas and the safety of the gas plumbing system against possible damage. These regulations include the following:
- Preventing gas poisoning due to incomplete combustion of gas appliances or the infiltration of toxic gases from combustion through cracks and openings in cement chimneys and metal chimneys into the space used by people, especially when sleeping.
- Minimizing the number of gas appliances in the indoor space to the minimum.
- Separating the gas plumbing system into multiple sections so that in abnormal conditions, each part can be disconnected from the circuit separately.
- Designing or installing the gas plumbing system, chimneys, and gas appliances in such a way that in the event of an incident or in the rush of people to escape, they are protected from collisions or damage.
- Providing adequate ventilation and completely transferring the combustion products of gas appliances outside the building.
- Installing signs indicating the location of quick gas shut-off valves and other emergency points in the plumbing system.
Designing Building Plumbing According to Domestic and Commercial Gas Plumbing Standards
Commercial centers or residential buildings must certainly have their own specific rules and regulations and be installed based on engineering principles so that they do not encounter challenges and problems during use. In this section, we will mention some of the rules that must be applied when designing the building plumbing systems and explain them.
Choosing the Gas Plumbing Route
When choosing the gas plumbing route, make sure that the pipe follows the safest and shortest path. Shared sections of the gas plumbing of residential units, such as risers, should not pass through private property. Ultimately, the gas pipe route should be chosen in such a way that it does not damage the main structure.
Preparing Plumbing System Maps
To prepare the gas plumbing system maps, you must have the following documents:
- Gas plumbing map in the ground and floor plans where the gas pipe is laid
- Location of chimneys with their specifications
- Isometric map with pipe length and diameter mentioned
- Building’s usable area in square meters and the gas consumption of each gas appliance connected to or will be connected to this plumbing system
- Sketch of the requested property location, which should be drawn on the application form with the address and location relative to main roads
Choosing the Gas Pipe Diameter
The diameter of gas pipes should be such that it can supply sufficient gas for the maximum consumption of the related gas appliance or appliances without causing a pressure drop of more than 12.7 millimeters of water column between the regulator and the gas appliances.
Maximum Allowable Nominal Diameter
The maximum allowable nominal diameter for gas plumbing with a pressure of 176 millimeters of water column is 100 millimeters or 4 inches.
- Required information for calculating the gas pipe diameter
- Maximum allowable pressure drop between the regulator and gas appliances
- Plumbing length
- Gas density
- Maximum gas consumption intended in the design
Determining the Longest Route
The longest route should be measured from the regulator outlet point to the farthest gas consumption point in the building.
Requirements for Installing Gas Plumbing System Components
In gas plumbing, besides complying with the domestic and commercial gas plumbing standards, the installation requirements of the plumbing system components are also necessary. These requirements include various items, which we will discuss by mentioning their names and relevant options.
1. Interface Plumbing (Plumbing Between Regulator and Meter)
- The beginning of the interface plumbing should be placed at the nearest point to the end of the riser.
- Suitable distance must be confirmed with the local gas company.
- The interface plumbing should have the shortest path and be visible. It should also be exposed.
- The route of the interface plumbing outside the property should not be in a place prone to damage.
- At the beginning of the interface plumbing, shutoff valves must be installed for each subscriber if the interface supplies more than one consumer.
2. Collector
- The collector should be made using standard fittings.
- Taking branches directly without using standard collector pipe fittings is prohibited.
- The collector diameter should not be smaller than the main pipe diameter.
3. Meter in Domestic and Commercial Gas Plumbing Standards
- The meter should be located within the property boundary, close to the entrance of the residential unit or the main building door.
- The meter should be installed where air flow is present. If there is a constant air flow, the meter can be installed in the lobby.
- On the branches taken from the collector, the meter should be installed at the closest point to the collector in a centralized location, making meter reading easy.
- The meter should be installed in such a way as to be protected from physical damage.
- The meter should not be installed in locations where fire risk or its escalation is possible.
- The meter installation location should be easily accessible for repair.
- The distance of the meter from electrical wires installed on the surface should be at least 10 centimeters, and from the electricity meter 50 centimeters.
- The distance of the meter from ignition sources such as a furnace or water heater should be at least one meter.
- The height of the meter pipe above the ground should be 180 centimeters.
4. Valves
- The valves used in gas plumbing should be quarter-turn ball valves.
- The diameter of branch valves should match the diameter of the gas pipe inlet of each building.
- If a property has multiple separate buildings, each building should have an independent shutoff valve besides the main shutoff valve.
- The main consumer valve should be installed immediately after the meter at a height of 180 centimeters from the ground.
5. Branch Valves
- Residential Unit Valve: In a building with more than one residential unit, a quick and complete gas shutoff valve should be installed at an appropriate location or height on the branch pipe of each unit, which is connected to the main pipes, ensuring it is not exposed to damage but accessible to residents.
- Riser Branch Valve: Should be installed at the beginning of branches that have more than one consumer.
- Gas Appliance Consumption Valve: At the end of the plumbing branch for each gas appliance, a consumption valve must be installed.
Conclusion
The standards for domestic and commercial gas plumbing have many specific rules and conditions. All these regulations and rules are designed to keep your life safe. Since the gas plumbing process is very sensitive, it should be entrusted to highly skilled and experienced technicians to ensure its standard and correct installation. We hope that reading this article has been helpful for you.
Source: achareh
