What do you do in the event that your garage door suddenly stops functioning?

Village of Mokena
Village
The gable bank barn at the historic McGovney–Yunker Farmstead
Flag Seal
Motto(s):  Planned Progress, Pleasant Living
Location of Mokena in Will County, Illinois.
Location of Illinois in the United States
Coordinates: 41°32′04″N 87°52′37″W / 41.534414°N 87.876873°W / 41.534414; -87.876873
Country	United States
State	Illinois
County	Will
Township	Frankfort, New Lenox
Incorporated	1880
Government
• Type	Village
Area [1]
• Total	8.68 sq mi (22.47 km2)
• Land	8.68 sq mi (22.47 km2)
• Water	0.00 sq mi (0.00 km2)
Population  (2020)
• Total	19,887
• Density	2,292.19/sq mi (885.05/km2)
Time zone	UTC-6 (CST)
• Summer (DST)	UTC-5 (CDT)
ZIP code	60448[2]
Area codes	708
FIPS code	17-49854
Website	http://www.mokena.org/

Mokena (/moʊˈkinə/ moh-KEE-nuh) is a village in Will County, Illinois, United States. It is a southwest suburb of Chicago. The population was 19,887 at the 2020 census. The Census Bureau's 2019 estimate found that the population had increased to 20,159.^[3]

Mokena is a name apparently derived from a Native American language meaning "turtle".^[4] While the particular language from which the name originates is not documented, likely candidates are Anishinaabemowin, whose word for "snapping turtle" is mikinaak,^[5] and its close sister language Potawatomi, in which the same animal is called mkenak.^[6] Both languages were once spoken in the area now occupied by the town.

Mokena is located at 41°32′4″N 87°52′37″W / 41.53444°N 87.87694°W / 41.53444; -87.87694.^[7] According to the 2010 census, Mokena has an area of 8.893 square miles (23.03 km²), of which 8.89 square miles (23.02 km²) (or 99.97%) is land and 0.003 square miles (0.01 km²) (or 0.03%) is water.^[8] It is bordered by Tinley Park to the northeast, Orland Park to the north, Homer Glen to the northwest, Frankfort to the south and New Lenox to the west.

Elementary school services are provided by one of four school districts: Mokena School District 159, New Lenox School District 122, Frankfort School District 157C, and Summit Hill School District 161. Schools within District 159 include MES (Mokena Elementary School), MIS (Mokena Intermediate School), and MJHS (Mokena Junior High School). Mokena is served by Lincoln-Way Community High School District 210; students living in districts 159 or 122 attend Lincoln-Way Central High School, and students living in districts 157C or 161 attend Lincoln-Way East High School. Higher education is provided at Joliet Junior College, the nation's first public community college, and at Rasmussen College.

As of the census^[10] of 2010, there were 18,740 people, 6,358 households, and 5,120 families residing in the village. The population density was 2,432.4 inhabitants per square mile (939.2/km²). There were 4,848 housing units at an average density of 808.6 per square mile (312.2/km²). The racial makeup of the village was 94.5% White, 1.3% African American, 0.01% Native American, 2.0% Asian, 0.01% Pacific Islander, 0.9% from other races, and 0.63% from two or more races. Hispanic or Latino of any race were 4.8% of the population.

As of the census of 2000, there were 4,703 households, out of which 48.5% had children under the age of 18 living with them, 73.7% were married couples living together, 7.3% had a female householder with no husband present, and 16.8% were non-families. 14.0% of all households were made up of individuals, and 3.3% had someone living alone who was 65 years of age or older. The average household size was 3.10 and the average family size was 3.46.

In the village, the population was spread out, with 32.4% under the age of 18, 7.1% from 18 to 24, 32.7% from 25 to 44, 21.5% from 45 to 64, and 6.2% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 101.5 males. For every 100 females age 18 and over, there were 97.3 males.

The median family income is $82,596 and the median income for a household is $91,817. Males had a median income of $58,226 versus $31,522 for females. The per capita income for the village was $31,944. As of 2008, the median house value was $350,130, up from $211,300 in 2000.^[11]

About 0.7% of families and 1.0% of the population were below the poverty line, including 0.6% of those under age 18 and 4.6% of those age 65 or over.

The Village of Mokena is serviced by the Metra rail service Rock Island District. Mokena has two commuter rail stations, Hickory Creek and Front Street, providing service to downtown Chicago's LaSalle Street Station, connecting with components of the Chicago Transit Authority. Mokena is also served by I-80, which runs along its northern border. Through I-80 commuters have convenient access to I-355 (Veteran's Memorial Tollway) and I-57. The main north–south thoroughfares are US Route 45 (LaGrange Rd) and Wolf Rd. The main east–west thoroughfares are 191st St, LaPorte Rd., and US Route 30 (Lincoln Highway). Rail freight traffic travels along both the Metra RI District Railway (Metra RI) and the Canadian National Railway (CN). The CN tracks run east/west along Mokena's southern boundary, while the Metra Rock Island District (Metra) tracks approximately bisect the town in a northeastern/southwestern direction.

• Dean Anna, MLB player; born in Mokena
• James Augustine, former University of Illinois and NBA player
• Terry Boers, sports radio host and Chicago Sun-Times columnist ^[12]
• Exene Cervenka, singer and writer; grew up in Mokena
• Karla DeVito, actress, voice actress, and singer; born in Mokena
• Clay Guida, mixed martial artist, Jason's brother^[13]
• Jason Guida, mixed martial artist, Clay's brother
• Don C. Hall, state actor and Wisconsin state legislator; lived in Mokena^[14]
• Ron Kittle, former MLB player, lives in Mokena^[15]
• Denise Richards, model and actress, lived in Mokena^[16]
• Bob Strait, racing driver; born in Mokena

• Mokena official website
• Mokena School District 159
• Frankfort School District 157C
• Summit Hill School District 161
• Wikimapia Contributions

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) This article possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (November 2012) (Learn how and when to remove this message) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Garage door" – news · newspapers · books · scholar · JSTOR (September 2012) (Learn how and when to remove this message) (Learn how and when to remove this message)

A garage door is a large door to allow egress for a garage that opens either manually or by an electric motor (a garage door opener). Garage doors are frequently large enough to accommodate automobiles and other vehicles. The operating mechanism is usually spring-loaded or counterbalanced to offset the door's weight and reduce the human or motor effort required to operate the door. Less commonly, some garage doors slide or swing horizontally. Doors are made of wood, metal, or fiberglass, and may be insulated to prevent heat loss.

A typical version of an overhead garage door used in the past would have been built as a one-piece panel.^[1] The panel was mounted on each side with an unequal parallelogram-style hinge lifting mechanism. Newer versions of overhead garage doors are now generally built from several panels hinged together that roll along a system of tracks guided by rollers.^[1] The weight of the door may be 400 lb (180 kg) or more but is balanced by either a torsion spring system or a pair of extension springs.^[2] A garage door opener is controlled motorized mechanism for opening garage doors adds convenience, safety, and security often used with a remote or a button on wall.^[3]

The history of the garage door could date back to 450 BC when chariots were stored in gatehouses, but in the United States, they arose around the start of the 20th century. As early as 1902, American manufacturers—including Cornell Iron Works—published catalogs featuring a "float over door." Evidence of an upward-lifting garage door can be found in a catalog in 1906.^[4]

This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (April 2023) (Learn how and when to remove this message)

Single-panel doors are constructed from one monolithic panel. A single panel door swings up and overhead with a hinge on each side (jamb-type hardware) to a fully open position from the closed position. A disadvantage of monolithic panel doors is that the swing-up arc of the door occurs partially outside the garage. This means a vehicle must stop and park several feet in front of the door to avoid being hit by the garage door when it is opened.

Single panel doors can also be installed with (one piece track type hardware) that folds the door back with a single horizontal track on each side (mounted at the top of the wood frame) and a roller mounted to the top of the door on each side. A hinge on each side that attaches to the bottom of each side of the garage door. Using track hardware, a car can be parked much closer to the door, as the door is positioned entirely inside the garage door header when in the open position. Track-type hardware has less arc when raising and lowering the garage door than jamb-type hardware.^{[citation needed]}

Sectional garage doors

Sectional doors usually have three to eight panels and slide up and overhead. Sectional doors occupy the same internal garage space as a monolithic door. Sectional doors have two advantages over single-panel monolithic doors:

• Sectional doors do not require any space outside the garage to open. A vehicle may park very close to the garage before opening the door.
• Each panel of a sectional door has its connection to the door track. This increases reliability and robustness compared to monolithic doors, which have only a few track connections for the whole panel.

Garage doors can be made of many materials, but steel, aluminum, wood, copper, glass, and vinyl (polyethylene) are the most popular materials. Some manufacturers incorporate foamed-in-place polyurethane insulation within the monolithic panel and sectional garage doors.

The side sliding sectional door^[5]

• A lot of space under the garage ceiling.
• Can use the entire ceiling of the garage.
• Fast access to the garage

Roller doors (sometimes called "sheet doors") are usually constructed of corrugated steel. They evolved from cover window and door coverings.^[4] Other materials can be used (e.g., transparent corrugated fiberglass) where strong impact resistance is not required. Corrugations give the door strength against impacts. A typical single-car garage roller door has a preloaded spring inside the rolling mechanism. The spring reduces the effort required to open the door. Oversized roller doors in commercial premises are not sprung (except in the US), and a manual pulley and chain system or a geared motor is used to raise and lower (roll up and roll down) the door. Roller doors cannot be effectively insulated.

In the UK (and other parts of the EU), 'insulated' roller garage doors are available, using an aluminum lathe filled with polyurethane foam for thermal and acoustic insulation.

Concerning thermal insulation, the roller door has a typical insulation R-value of 4.9 to 5.2. A sheet steel garage door has a typical insulation R-value of 0.5 to 2.7.

An application that needs more thermal insulation typically uses a foam-filled sectional garage door, which provides typical insulation R-values of 6.1 to 6.4.

• Aluminum garage doors are usually found in commercial settings and are uncommon for residential ones. Aluminum is typically only used for full-view garage doors (doors that are made up of glass sections divided by aluminum stiles). Aluminum doors are rust-proof and low maintenance.
• Fiberglass and vinyl garage doors are composite units, combining a steel core behind a fiberglass or vinyl skin. They also have polyurethane insulated base sections or other types of foam insulation. These premium doors can match steel garage doors and be a realistic imitation of wood (namely fiberglass units), but they may be more expensive than steel units. Fiberglass doors are commonly used near an ocean, where salt water can ruin regular steel doors.
• Steel doors have a variety of sizes and styles, provide strength and security, are cost-competitive, and may have optional insulating value. Extra strength is available with two or three layers of galvanized steel with a low gauge number (0.6 - 0.7 mm steel panels).^[6]
• Wood garage doors offer aesthetic appeal, but they are high maintenance and may be expensive. Low-priced wood garage doors may warp and break easily.

A common material for a new garage door is a steel sheet formed or stamped to look like a raised panel wooden door. Steel doors are available in uninsulated, insulated, and a three-layer door, also known as a sandwich-style door. A design mimicking carriage house doors has become popular since the early 2000s, and many manufacturers clad the exterior of a steel door with composite, vinyl boards, or other trim to give it the appearance of wood.

In situations involving residential attached garages, the insulating value and the energy efficiency of a garage door are essential to avoid overheating and freezing problems, as well as for comfort and energy savings.

A torsion spring counterbalance system consists of one or two tightly wound-up springs on a steel shaft with cable drums at both ends. The apparatus mounts on the header wall above the garage door and has three supports: a center bearing plate with a steel or nylon bearing and two end bearing plates at both ends. The springs consist of a steel wire with a stationary cone at one end and a winding cone at the other. The stationary cone is attached to the center bearing plate. The winding cone consists of holes every 90 degrees for winding the springs and two set screws to secure the springs to the shaft. Steel counterbalance cables run from the roller brackets at the bottom corners of the door to a notch in the cable drums. When the door is raised, the springs unwind, and the stored tension lifts the door by turning the shaft, thus turning the cable drums and wrapping the cables around the grooves on the cable drums. When the door is lowered, the cables unwrap from the drums, and the springs are rewound to full tension.

Garage door manufacturers typically produce doors fitted with torsion springs that provide a minimum of 10,000 to 15,000 cycles and are guaranteed for three to seven years. One cycle is a single opening and closing sequence. Most manufacturers offer a 30,000-cycle spring. However, it is essential to remember that if the garage door's weight is increased by adding glass, additional insulation, or even several coats of paint, the torsion spring's life may be significantly reduced. Additionally, springs in highly humid environments, such as coastal regions tend to have a significantly shorter cycle life, due to the corrosive cracking.

Other factors like poor garage door maintenance, loose tracks, or components shorten torsion spring life. Owners are advised to avoid applying grease to garage door tracks because that makes the wheels "skate" in the track instead of turning on their bearings. Only bearings, hinges, and spring wire require lubricant.

An extension spring counterbalance system consists of a pair of stretched springs running parallel to the horizontal tracks. The springs lift the door through a system of pulleys and counterbalance cables running from the bottom corner brackets through the pulleys. When the door is raised, the springs contract, thus lifting the door as the tension is released. Typically, these springs are made of 11 gauge (3 mm) galvanized steel, and the lengths of these springs are based on the height of the garage door in question. Their lifting weight capacity can best be identified by the color that is painted on the ends of the springs.

Maintenance of garage doors is described in the manufacturer's instructions and consists of periodic checks for correct operation, visual inspection of parts, and lubrication. ^[7][8]

Garage doors can cause injury and property damage (including expensive damage to the door itself) in several ways. The most common causes of injury from garage door systems include falling doors, pinch points, improperly adjusted opener force settings, and safety eyes, attempts at do-it-yourself repair without the proper knowledge or tools, and uncontrolled release of spring tension (on torsion spring systems).

A garage door with a broken spring or the wrong strength can fall. Because the effective mass of the door increases as the garage door sections transfer from the horizontal to vertical door tracks, a falling garage door accelerates rapidly. A free-falling garage door can cause severe injury or death.

The sections and rollers on garage doors represent a significant pinch hazard. Children should never be allowed near a moving garage door for this reason. On manually operated garage doors, handles should be installed vertically to promote "vertical orientation of the hand".

Mechanical garage door openers can pull or push a garage door with enough force to injure or kill people and pets if they become trapped. Modern openers have “force settings” that make the door reverse if it encounters too much resistance while closing or opening. Any garage door opener sold in the United States after 1992 requires safety eyes—sensors that prevent the door from closing if obstructed. Force settings should cause a door to stop or reverse on encountering more than approximately 20 lb (10 kg) of resistance. Safety eyes should be installed a maximum of six inches above the ground. Many garage door injuries, and nearly all garage door-related property damage, can be avoided by following these precautions.^[9]

Certain parts, especially springs, cables, bottom brackets, and spring anchor plates, are under extreme tension. Injuries can occur if parts under tension are removed.

Extension spring systems should always be restrained by a safety cable that runs through the middle of the spring, tying off to a solid point at the rear and front of the horizontal door track. The safety cable prevents hazards to bystanders when a spring, pulley, or cable breaks under tension and makes the system relatively safe.

Torsion spring systems can be hazardous as they are always under tension and release energy when the spring fails. Severe injury or death can be caused by the projectile pieces of a failed torsion spring. Many people have been injured or killed trying to adjust torsion springs, and special training and procedures are required to modify a torsion spring safely; it is a job for a professional, not a homeowner or DIYer.

Media related to Garage doors at Wikimedia Commons

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Garage door opener" – news · newspapers · books · scholar · JSTOR (April 2015) (Learn how and when to remove this message)

A garage door opener is a motorized device that opens and closes a garage door controlled by switches on the garage wall. Most also include a handheld radio remote control carried by the owner, which can be used to open and close the door from a short distance.

The electric overhead garage door opener was invented by C.G. Johnson in 1926 in Hartford City, Indiana.^[1] Electric Garage Door openers did not become popular until Era Meter Company of Chicago offered one after World War II where the overhead garage door could be opened via a key pad located on a post at the end of the driveway or a switch inside the garage.^[2]

As in an elevator, the electric motor does not provide most of the power to move a heavy garage door. Instead, most of door's weight is offset by the counterbalance springs attached to the door. (Even manually operated garage doors have counterbalances; otherwise, they would be too heavy for a person to open or close them.) In a typical design, torsion springs apply torque to a shaft, and that shaft applies a force to the garage door via steel counterbalance cables. The electric opener provides only a small amount of force to control how far the door opens and closes. In most cases, the garage door opener also holds the door closed in place of a lock.

The typical electric garage door opener consists of a power unit that contains the electric motor. The power unit attaches to a track. A trolley connected to an arm that attaches to the top of the garage door slides back and forth on the track, thus opening and closing the garage door. The trolley is pulled along the track by a chain, belt, or screw that turns when the motor is operated. A quick-release mechanism is attached to the trolley to allow the garage door to be disconnected from the opener for manual operation during a power failure or in case of emergency. Limit switches on the power unit control the distance the garage door opens and closes once the motor receives a signal from the remote control or wall push button to operate the door.^[3]

The entire assembly hangs above the garage door. The power unit hangs from the ceiling and is located towards the rear of the garage. The end of the track on the opposite end of the power unit attaches to a header bracket that is attached to the header wall above the garage door. The powerhead is usually supported by punched angle iron.

Recently another type of opener, known as the jackshaft opener, has become more popular.^[when?] This style of opener was used frequently on commercial doors but in recent years has been adapted for residential use. This style of opener consists of a motor that attaches to the side of the torsion rod and moves the door up and down by simply spinning the rod. These openers need a few extra components to function safely for residential use. These include a cable tension monitor, to detect when a cable is broken, and a separate locking mechanism to lock the door when it is fully closed. These have the advantage that they free up ceiling space that an ordinary opener and rail would occupy. These also have the disadvantage that the door must have a torsion rod to attach the motor to.

There are five types of garage door openers:

1. Chain drive openers. These have a chain (similar to a bicycle's) that connects the trolley to the motor.
2. Belt drive openers use a rubber belt in place of a chain.
3. Screw drive openers have a long screw inside the track. The trolley connects to this screw.
4. Direct drive openers have the motor installed inside the trolley and use a gear wheel to guide the trolley along a fixed chain.
5. Jackshaft openers mount on the wall at either end of the torsion bar.

The first wireless garage door openers were invented and developed by two US inventors at the same time, one in Illinois and the other in Washington state, around 1930. They were unknown to each other.^[4]

The first garage door opener remote controls were simple and consisted of a simple transmitter (the remote) and receiver which controlled the opener mechanism. The transmitter would transmit on a designated frequency; the receiver would listen for the radio signal, then open or close the garage, depending on the door position. The basic concept of this can be traced back to World War II. This type of system was used to detonate remote bombs. While novel at the time, the technology ran its course when garage door openers became popular. While the garage door remote control transmitter is low power and has limited range, its signal can be received by other, nearby, garage door openers. When two neighbors had garage door openers, then opening one garage door might open the neighbor's garage door as well.

The second stage of the wireless garage door opener system solved the opening-the-neighbor's-garage-door problem. The remote controls on these systems transmitted a digital code, and the receiver in the garage responded only to that code. The codes were typically set by eight to twelve DIP switches on the receiver and transmitter, so they allowed for 2⁸ = 256 to 2¹² = 4,096 different codes. As long as neighbors used different codes, they would not open each other's garage doors. The intent of these systems was to avoid interference with nearby garage doors; the systems were not designed with security in mind. Intruders were able to defeat the security of these systems and gain entry to the garage and the house. The number of codes was small enough that even an unsophisticated intruder with a compatible remote control transmitter could just start transmitting all possible codes until he found one that opened the door. More sophisticated intruders could acquire a black box master key that automatically transmitted every possible code in a short time. An even more sophisticated method is known as a replay attack. The attacker would use a code grabber, which has a receiver that captures the remote's digital code and can retransmit that digital code at a later time. The attacker with a code grabber would wait nearby for the homeowner to use his remote, capture the code, and then replay the code to open the door when the homeowner was gone. Multicode openers became unpopular in areas where security was important, but due to their ease of programming, such openers are often used to operate such things as the gates in gated apartment complexes.

An intermediate stage of the garage door opener market eliminated the DIP switches and used remotes preprogrammed to one out of roughly 3.5 billion unique codes. The receiver would maintain a security list of remotes to which it would respond; the user could easily add the unique remote's code to the list by pressing a button on the garage door opener while activating the remote control. A large number of codes made the brute force try-all-possible-digital-codes attacks infeasible, but the systems were still vulnerable to code grabbers. For user convenience, these systems were also backward compatible with the older DIP switch remote codes, but adding an old technology remote to the security list made the garage door opener vulnerable to a brute force attack to find the DIP switch code. The larger code space approach was an improvement over the fixed DIP switch codes but was still vulnerable to the replay attack.

The third stage of garage door opener technology uses a frequency spectrum range between 300-400 MHz and rolling code (code hopping) technology to defeat code grabbers. In addition to transmitting a unique identifier for the remote control, a sequence number and an encrypted message are also sent. Although an intruder could still capture the code used to open a garage door, the sequence number immediately expires, so retransmitting the code later would not open the garage door. The encryption makes it extremely difficult for an intruder to forge a message with the next sequence number that would open the door. Some rolling code systems are more involved than others. Because there is a high probability that someone will push the remote's button while not in range and thus advance the sequence number, the receiver does not insist the sequence number increase by exactly one; it will accept a sequence number that falls within a narrow window or two successive sequence numbers in a much wider window. Rolling code technology is also used on car remote controls and with some internet protocols for secure sites.

The fourth stage of garage door opener systems is similar to third stage, but it is limited to the 315 MHz frequency. The 315 MHz frequency range avoids interference from the land mobile radio system (LMRS) used by the U.S. military.

The following standards are used by units manufactured by Chamberlain (including LiftMaster and Craftsman):

* Does not apply to keyless entry keypads or universal remotes.

Recent Chamberlain garage door openers that have Security+ 2.0 features also use a special serial protocol on wired connections rather than a simple switch closure.^[5]

The following standards are used by units manufactured by Overhead Door Corporation and its subsidiary The Genie Company†:

† Note: There are no standard color codes for the learn button or LED on units manufactured by Overhead Door or Genie. All accessories made for later versions of Genie Intellicode and Overhead Door CodeDodger are backward compatible with previous generations of Intellicode and CodeDodger.

Many garage door opener remote controls use fixed-code encoding which use DIP switches or soldering to do the address pins coding process, and they usually use pt2262/pt2272 or compatible ICs. For these fixed-code garage door opener remotes, one can easily clone the existing remote using a self-learning remote control duplicator (copy remote) which can make a copy of the remote using face-to-face copying.

Additional features that have been added over the years have included:

• Automatic courtesy lights that turn on when the door opens (or via motion sensors) and automatically turn off after a preset delay
• A remote lockout feature, which turns off the radio receiver while one is on vacation or away for an extended time.
• The availability of accessories has increased, including such features as wireless keypads, key chain remotes, and solenoid-operated deadbolts to lock the door itself.
• Automatic door closing feature, which after a fixed time by the owner, closes the garage door to prevent theft.

More sophisticated features are also available, such as an integrated carbon monoxide sensor to open the door in case of the garage being flooded with exhaust fumes. Other systems allow door activation over the Internet to allow home owners to open their garage door from their office for deliveries.

Another recent innovation in the garage door opener is a fingerprint-based wireless keypad. This unit attaches to the outside of the garage door on the jamb and allows users to open and close their doors with the press of a finger, rather than creating a personal identification number (PIN). This is especially helpful for families with children who may forget a code and are latchkey kids.

The garage door is generally the largest moving object in a home. An improperly adjusted garage door opener can exert strong and deadly forces and might not reverse the garage door in an emergency. The manufacturer's instructions provide guidance to the user on the proper adjustment and maintenance of the opener.

Garage door openers manufactured and installed in the United States since 1982 are required to provide a quick-release mechanism on the trolley that allows for the garage door to be disconnected from the garage door opener in the event of entrapment.^[8] Garage door openers manufactured since 1991 are also required to reverse the garage door if it strikes a solid object.^[9][10]

In the United States, the Consumer Product Safety Improvement Act of 1990 required that automatic residential garage door operators manufactured on or after 1 January 1991 conform to the entrapment protection requirements of the 1988 version of ANSI/UL standard 325.^[11] A requirement for redundant entrapment-prevention devices was added in 1993; such a system can use an electric eye, a door edge sensor, or any other device that provides equivalent protection by reversing the travel of the closing door if an object is detected in its path.^[12][13]

In California, Senate Bill No. 969 requires that any automatic residential garage door opener that is manufactured for sale, sold, offered for sale, or installed in a residence to have a battery backup function that is designed to operate when activated because of an electrical outage.^[14] The bill went into effect on July 1, 2019. Under the bill, any automatic garage door opener that is in violation is subject to a civil penalty of $1000.

The bill was passed by Gov. Jerry Brown on Sept. 21, 2018, in response to the 2017 California Wildfires in which at least 5 individuals lost their lives because they could not open their garage door when the power went out.^[15]

The Door and Access Systems Manufacturers Association International opposed the bill arguing that garage door openers with backup batteries require regular maintenance and that the bill should be amended to make this clear. In addition, they said that "garage door openers with backup batteries are not designed to serve as life safety devices, and should not be relied upon to prove a means of egress from a garage during an electrical outage."^[16]

The bill passed, despite most garage doors having a release pull cord.

• Official FCC notification on garage opener frequencies (PDF)
• Garage Door Opener Safety Tips (Washington Post)
• Safety Commission Rules For Automatic Garage Door Openers - U.S. Consumer Product Safety Commission. CPSC, 1992