Codes and standards
Detailed description of codes and standards
Environmental conditions
ASHRAE Standard 55 (2020)
ASHRAE Standard 55 – Thermal Environmental Conditions for Human Occupancy (2020) specify the combinations of indoor thermal environmental factors and personal factors that will produce satisfactory thermal environmental conditions for a majority of the occupants within the space. The ASHRAE 55 is applicable worldwide and incorporated in other countries standards (e.g., the Brazilian ABNT NBR 16401-2 review proposed in 2021)
ASHRAE 55 (2020) outlines methods to determine satisfactory thermal conditions. The analytical comfort zone method predicts the thermal sensation mean vote (PMV) of a representative occupant based on the six factors indicated in the previous section (Factors of thermal comfort). PMV is an index that predicts the average vote of thermal sensation on a scale from –3 (cold) to +3 (hot), where a score of 0 would be considered neutral condition, not too cool nor too warm. The standard defines the interval between –0.5 and +0.5 PMV as required condition to achieve thermal comfort. This model is applicable for air speed up to 0.2 m/s [40 fpm]. For higher air speed the Elevated Air Speed Comfort Zone Method should be applied. This method uses the same six factors and is defined based on the same comfortable interval of ± 0.5 PMV. However, the thermal conditions are calculated based on the Standard Effective Temperature (SET) index which is more reliable for considering the heat loss effect of increased air speed. ASHRAE 55 (2020) also includes the Adaptive Model, which is applicable for natural conditioned spaces where occupants can open and close external openings and can adjust their clothes (e.g., take of a jacket). This model considers the increment of air speed can offset the maximum temperature limits in a space.
ASHRAE 55 (2020) presents a Design Thermal Environmental Control Classification that ranks spaces with more control options in a higher level for occupant comfort. This captures the beneficial effects of increased opportunities for local and group level control of thermal comfort as indicated in Table 5. The standard also determines desk fans should have to be capable of providing air speed at the occupant’s head/face/upper body within range of 0.36 to 0.8 m/s [71 to 160 fpm].
Table 5. ASHRAE 55-2020 Comfort control classification levels (CCCLs)
1
Each occupant is provided two or more control measures for their personal environment.
Private office with a ceiling fan and an occupant adjustable thermostat
Shared office with desktop fans and seat warmers for each occupant
2
Each occupant is provided one control measure for their personal environment.
Private office with an occupant adjustable thermostat
Shared office with a desktop fan for each occupant
3
The room provides multi occupant control of at least two control measures in their shared environment.
Shared office with an occupant adjustable thermostat and ceiling fan control
4
The room or thermal zone provides multi occupant control of one control measure in their shared environment.
Shared office with an occupant adjustable thermostat
5
No occupant control of any environmental factors
Shared or private office with an un-adjustable thermostat or no thermostat
Green Mark Scheme - Singapore
Green Mark is a green building certification scheme established by the Building and Construction Authority (BCA) tailored for tropical climate aiming to raise standards in energy performance and emphasis on other sustainability outcomes. Singapore is located in the Tropics with a yearly average outdoor air temperature around 30 °C [86 °F], which indicates a great potential for application of increased air movement.
In Green Mark 2021: Health and Wellbeing section, strategy of hybrid cooling system (i.e., increasing temperature setpoint in HVAC system with provision of elevated air speed by ceiling fans and/or individual fans) is highlighted to enhance thermal comfort in air-conditioned non-residential buildings. Thermal comfort can be achieved by controlling the temperature of conditioned air and by adjusting air speed via fans. The Technical Guide of Green Mark for existing non-residential buildings (2021) allows for the use of elevated temperatures in a Hybrid cooling system, with increased air speed to meet thermal comfort criteria (-0.5 < PMV < 0.5, and/or PPD < 10 %) through ASHRAE Standard 55, ISO 7730, or EN 15251 (substituted by EN 16798) methodologies. This setpoint temperature operates in the fan-integrate AC system is higher than the setpoint recommended in the Singapore Standard 553 (2016): Code of practice for air-conditioning and mechanical ventilation in buildings, i.e., room temperature should be maintained within 23-25 °C [73-77 °F], for conventional air-conditioning (without fan) settings, meaning that energy saving through increased temperature setpoint in the HVAC system is achievable.
Ceiling fans testing regulations
In 2017, the US Department of Energy (DOE) published the Energy Conservation Standards for Ceiling Fans (Federal Register 82:6826). This regulation proposes a fan testing procedure to allow comparison of products based on electric input power and airflow. These test criteria are based on common industry protocols and used by fan manufacturers as the basis of published ceiling fan performance data.
Small-diameter fans: Method for ENERGY STAR qualified ceiling fans
Small-diameter ceiling fan is a ceiling fan that is smaller than (or equal to) 2.1 m [7 ft] in diameter. Performance testing on small-diameter ceiling fan is based on the ENERGY STAR Testing Facility Guidance Manual: The Solid State Test Method for ENERGY STAR Qualified Ceiling Fans. This guidance provides detailed information on how to properly test the performance a ceiling fan, including the construction and preparation of the test room, equipment that are needed for the test, equipment set-up, testing procedures, and criteria in reporting test results.The qualifying fans shall meet or exceed the minimum airflow and efficiency requirements at its low fan speed (1250 CFM; 155 CFM/W), medium fan speed (2500 CFM; 110 CFM/W) and high fan speed (5000 CFM; 75 CFM/W).
Large-diameter fans: AMCA Standard 230
Large-diameter ceiling fan is a ceiling fan that is larger than 2.1 m [7 ft] in diameter. Performance testing on larger-diameter ceiling fan is standardized by the Air Movement and Control Association (AMCA) Standard 230-15: Laboratory Methods of Testing Air Circulating Fans for Rating and Certification. Similarly, this standard provides a protocol and testing conditions to assess the performance of different fan models, in particular determining and expressing ceiling fan efficiency and efficacy.The fan efficiency, adopted by Department of Energy (DOE) in the United State of America, is calculated using a weighted average of data collected in standby model and up to five available fan speed (if five speeds are tested, each speed is assumed 20% of the daily operating hours). Similar approaches could be applied to other countries as an additional instrument for estimating fans’ energy consumption and efficiency. The equation for the DOE efficiency is presented below:
A major consideration in using the DOE metric is when the fan operates at a very low speed. Power consumption is proportional to the cube of flow rate. Therefore, slowing down a fan would reduce the input power and airflow, but the reduction in input power is higher than airflow. Low airflow fans with inefficient motors can still achieve high DOE metric values. Conversely, high airflow fans (at the same diameter), even equipped with more efficient motors, are more difficult to comply with the DOE metric.
Large-diameter fans: Ceiling Fan Energy Index (CFEI)
Since 2021, the Ceiling Fan Energy Index (CFEI) has been used to make inefficient fans less likely to comply using slower speeds, such as those used to game the DOE (CFM/W) metric and to remove the unintentional barrier to compliance for high-performing high-utility fans. CFEI is derived from the FEI equation in ANSI/AMCA Standard 208-18: Calculation of the Fan Energy Index with substitute coefficient of airflow constant: Q0 = 12.5 m³/s (26500 CFM), pressure constant: P0 = 0.67 pascals (0.0027 inches water gauge), and fan-efficiency constant: η0 = 42 %. CFEI is calculated as a ratio of a reference fan's electrical input power to the actual fan's electrical input power. The equation is presented below:
The reference fan is a conceptual fan that relates all fans to a common baseline, producing the airflow and fan pressure required at a specified electrical input power. According to the standard, large-diameter ceiling fans should have a CFEI greater than or equal to: (a) 1.00 at high (i.e., 100 %) fan speed and (b) 1.31 at 40 % of fan speed.
ASHRAE Standard 216
ASHRAE Standard 216: Methods of Test for Determining Application Data of Overhead Circulator Fans aims to provide standardized performance data for the application of overhead circulation ceiling fans in indoor spaces. The room air speed distribution test results can be used to calculate occupant thermal comfort and to demonstrate compliance with the thermal comfort requirements of ASHRAE Standard 55. This standard includes requirements for test instrumentation, the features of test rooms, and measurement procedures. It also includes calculation procedures for several performance metrics relevant to thermal comfort application of overhead circulator ceiling fans such as uniformity, room average cooling effect, heating draft risk, and comfort cooling efficacy.
This standard provides a consistent industry-standard practice for determining ceiling fan performance characteristics. Manufacturers can use Standard 216 test procedures to test their products and provide standardized performance data for use in specification and simulation of fan performance. Standard 216 test procedures should also be used for any full-scale fan test mock-ups. In conjunction with the Design Thermal Environmental Control Classification of ASHRAE Standard 55, this standard supports the implementation of ceiling fans as an option for thermal comfort control in buildings.
IEC 60879:2019
The IEC 60879:2019 titled: "Comfort fans and regulators for household and similar purposes - Methods for measuring performance" is a standard for the measurement of the performance of household comfort fans. It encompasses various types of fans such as ceiling, tower, table, wall, and bladeless fans, with rated voltage up to 250 V for single-phase fans and 480 V for other types. Additionally, it includes fans with a rated power input of less than 125 W. The standard is used in Europe and developed by the International Electrotechnical Commission. According to the standard, a "comfort fan" is a "fan primarily designed for creating air movement around or on part of a human body for personal cooling comfort, including fans that can perform additional functionalities such as lighting".
Fire safety and installation
Fire code requirements
The primary concern with ceiling fans in relation to the fire code is the interaction with fire sprinklers. For the most part, standard ceiling fans in typical residential and non-residential applications have few limitations in relation to fire sprinklers, while large-diameter ceiling fans require a higher degree of integration with fire suppression systems.
The California Fire Code (Title 24, Part 9) cites the requirements of the National Fire Protection Association’s NFPA 13, “Standards for the Installation of Sprinkler Systems” and NFPA 13R, “Standard for the Installation of Sprinkler Systems in Low-Rise Residential Occupancies” govern the use of fire sprinklers in buildings.
Per NFPA 13, for ceiling fans less than 1.5 m [60 in] in diameter where the blades are less than 50 % of the swept area in plan view, fire sprinklers can be located without regard to the fan blades (Ref: NFPA 13 2016 sections 8.6.5.2.1.10, 8.7.5.2.1.6, 8.8.5.2.1.9, 8.9.5.2.1.6; NFPA 13 2019 sections 10.2.7.2.1.10, 11.2.5.2.1.9, 12.1.10.2.1.9). Since the above requirement specifically calls out “fan blades,” there may be cases where other parts of the ceiling fan, such as motor housing or mounting pendants (or fan blades that are less than 50% open in plan view), are considered obstructions to fire sprinklers. In most cases, for any motor housing, mounting pendant, or other part of the fan that is 46 cm [18 in] or less below the level of the sprinkler deflector, the so-called “rule of three” applies, where sprinklers must be placed away from the obstruction a minimum distance of three times the maximum dimension of the obstruction, up to 61 cm [24 in] (Ref: NFPA 13 2016 section 8.6.5.2.1.3; NFPA 13 2019 section 10.2.7.2.1.3). In other words, if the motor housing of a ceiling fan is 18 cm [7 in] in diameter, any fire sprinklers should be located at least 53 cm [21 in] from the motor housing. In the 2019 version of NFPA 13, for extended coverage sprinklers and residential sprinklers, this requirement is increased to a distance of four times the maximum dimension of the obstruction, up to 91 cm [36 in] (Ref: NFPA 13 2019 sections 11.2.5.2.1.3 and 12.1.10.2.1.3).
NFPA 13R requirements are more explicit about sprinkler locations in relation to obstructions such as ceiling fans. In these cases, the standards require pendant sprinklers to be a minimum of 1 m [3 ft] from any ceiling fan (Ref: NFPA 13R 2016 and 2019 section 6.4.6.3.4.1), and sidewall sprinklers to be at least 1.5 m [5 ft] from any ceiling fan (Ref: NFPA 13R 2016 and 2019 section 6.4.6.3.5.1). Though the standards do not explicitly state where those distances are measured from, this is typically interpreted as being the distance from the center point of the ceiling fan.
For larger format fans, NFPA 13 lays out more detailed requirements: (1) Fans must be no more than 7 m [24 ft] in diameter; (2) Each fan must be approximately centered between four adjacent sprinklers; (3) The vertical distance from fan blade to sprinkler deflector must be at least 1 m [3 ft]; and (iv) All fans must be interlocked to shut down immediately upon receiving a waterflow signal from the alarm system in accordance with the requirements of NFPA 72.
The California Fire Codes also specify that smoke alarms and smoke detectors shall not be installed withing a 36-inch (91 cm) horizontal path from the tip of the bade of a ceiling-suspended (paddle) fan unless the room configuration restricts meeting this requirement (907.2.11.8)
While this section covers requirements as they apply in the California Fire Code, adapted from NFPA Standards, specific requirements may vary by local jurisdiction. Always consult local codes for requirements for a specific project.
Seismic requirements
In many applications, standard ceiling fans attached directly to a structural ceiling do not require any further seismic bracing or restraint. However, applications with large-diameter ceiling fans, suspended ceilings, long suspension rods, or other special conditions may require additional seismic support.
Seismic considerations and requirements are especially relevant for installations of ceiling fans in California. Per the California Building Code, non-structural components that are permanently attached the structure, such as ceiling fans, must be installed to resist the effects of earthquake motions in accordance with the ASCE 7 standard (from the American Society of Civil Engineers, California Building Code, 2016, Part 2, Vol 2, Section 1613.1). The exact requirements in ASCE 7 will vary depending on the size, weight, and configuration of the fan, the strength of the expected seismic forces for the area, and the building type where it is installed.
In addition to the specific requirements in ASCE 7, there are some general best practices for all applications and scenarios. The Federal Emergency Management Agency’s (FEMA) document, “Reducing the Risks of Non-structural Earthquake Damage – A Practical Guide” recommends that all suspended fixtures, such as lighting and ceiling fans, have positive attachment to the structure to avoid falling hazards. Ceiling fans should never be supported on a suspended ceiling grid or ceiling tile. In addition, the California Department of the State Architect (DSA) has issued code interpretations pertaining to suspended fixtures such as ceiling fans, stating that fixtures with rigid suspension pendants must be attached to the structure using a device allowing movement in any direction (i.e., a ball and socket joint) (DAS IR 16-9) and requiring bracing where any pendant fixture passes through a suspended ceiling (DAS IR 25-2). Some manufacturers also suggest lateral restraint using guy wires that are at least 6.35 mm [0,25 in] in diameter for large-diameter fans. Again, it is important to consult local building codes to determine specific requirements.
Energy information label for ceiling fan
The Energy Protection Act (EPA) requires any ceiling fan to be tested in approved laboratory before it can be sold in the United States. The airflow and corresponding wattage at different operating speeds of the ceiling fan will be tested. Thereafter, the fan will be given an airflow rating (cubic feet per min), electricity use rating (watt, excludes lights), and an airflow efficiency rating (cubic feet per minute per watt). All the numbers will be printed on an energy Information label outside the fan packaging. This label helps the fan buyers to clarify the efficiency of fan products and to compare their needs between fan types.
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