Department of Labor Seal photos representing the workforce - digital imageryŠ copyright 2001 photodisc, inc.
Department of Labor Seal www.osha.gov  MyOSHA[skip navigational links] Search  Advanced Search | A-Z Index

eTools Home : Evacuation Plans and Procedures Viewing / Printing Instructions | Credits
Evacuation eToolEvacuation eToolEvacuation eToolEvacuation eToolEvacuation eToolEvacuation eTool


Workplace Evaluation - Alarm Systems

The purpose of the employee alarm systems standard 1910.165 is to reduce the severity of workplace accidents and injuries by ensuring that alarm systems operate properly and procedures are in place to alert employees to workplace emergencies.

This section will help you to understand alarm system requirements for warning employees when a hazardous condition or event occurs. 		  Print a checklist
Fire alarm box


Does the standard apply to me?
OSHA's employee alarm systems standard 1910.165 applies to all employers that use an alarm system to satisfy any OSHA standard that requires employers to provide an early warning for emergency action, or reaction time for employees to safely escape the work place, the immediate work area, or both.

This standard also applies to you if an OSHA standard specifically states that you must install an employee alarm system. For example, some standards that specifically require or reference alarm systems include:

Business people in meeting


Types of employee alarms
An employee alarm system can be any piece of equipment and/or device designed to inform employees that an emergency exists or to signal the presence of a hazard requiring urgent attention. The two most common types of alarms are audible and visual devices.

Audible Alarms:

Audible alarms include bells, horns, sirens, voice announcement systems, and other devices that can be distinguished above and apart from the normal sound level within the workplace.

Bells
Vibrating bells are the most common signal device. Bells are commonly used in schools for fire alarms.
Bell
Horn Horns
Horns produce a very loud distinctive sound that immediately attracts attention. Horns can be useful to call attention to critical situations.
Sirens
Sirens produce a loud piercing wail that makes them ideally suitable for initiating a site-wide evacuation.
Siren
Portable Radio Workplace Announcement System
Speakers can be used to play a live or recorded voice message. They are often ideally suited for large workplaces where phased or guided evacuations are needed.


Visual Alarms

Visual alarms use steady, flashing, or strobe lights to alert workers to an emergency situation in areas where noise levels are high, especially where ear protection must be worn and audible signals may not be heard or may be misunderstood. Visual signals also provide an effective way to alert workers with hearing loss about an emergency.

Flashing/Steady Lights
These lights are well suited for areas where ambient noise makes audible signals difficult to hear. These types of lights come with different colored covers for increased attention and can be ordered with rotating or flashing lights.
Flashing light
Strobe light Strobe Lights
Strobe lights use high intensity flash tubes that are ideally suited for areas where high ambient light levels make traditional rotating or flashing lights difficult to distinguish or where ambient noise makes audible signals difficult to hear.


Installation and restoration
Various alarmsFor alarm systems to provide adequate notification in the event of an emergency, they must be appropriate for the location you want to protect and either approved by an independent testing laboratory or they must be: 1910.165(c)(1)
  • Capable of being heard, seen, or otherwise perceived by everyone in the workplace;1910.165(b)(2)
  • Distinctive and easily identified by all employees as a signal to evacuate the work area or perform actions identified in your emergency response plan, such as "shelter-in-place"; 1910.165(b)(3)
  • Supervised if they were installed after January 1, 1981 and contain circuitry that is capable of being supervised. These systems must also provide positive notification to assigned personnel whenever a deficiency exists in the system. 1910.165(d)(4)

Alarm Selection Guidelines To get the most from an alarm system, follow these guidelines when selecting devices:
  • Make sure the alarm's sound is as different from the background noise and light as possible. Audible alarms should exceed the ambient noise level by at least six decibels. The light intensity for visual alarms should be at least 75 candela.
  • Use alarms with integrated audible and visual signals to accommodate the hearing and visually impaired, and for areas where a person may be working alone. This includes areas such as restrooms, storage areas, offices, and similar areas. (These devices are available for about the same cost as an audible or visual signal alone).
Did you know?
Research indicates high-intensity xenon strobe lamps to be the most effective and white light the most discernible. Colored lamps, particularly red, were found to be ineffective even at very high intensities.
  • Avoid using strobe devices that flash at rates above five flashes per second (fps). Rates above five fps can trigger seizures in people with certain forms of epilepsy. When multiple devises are used, either synchronize or reduce their flash rate so that the combined rate does not exceed five fps.

Protection of Alarms To make sure devices stay operable, follow these guidelines:
  • Alarm system components that may be exposed to corrosive environments should be either made or coated with a non-corrosive material.
  • Position alarm devices away from or out of contact with materials or equipment which may cause physical damage.
  • Alarms that are installed outdoors and need to be shielded from the weather to work properly must be protected with a canopy, hood, or other suitable device.
  • All devices should be securely mounted to a solid surface, such as screwed to a junction box with a mounting plate or other appropriate method that prevents them from putting pressure or stress on attached wires or tubing.

Alarm Placement Guidelines To ensure your alarm system provides adequate coverage, follow these guidelines when placing alarm devices:
  • Put at least one visual alarm in each room and any other general usage areas (guest restrooms, meeting rooms) which may be occupied by those with hearing impairments. You may need more than one alarm per room for those that exceed the manufacturer's spacing requirements. For example, if your alarm is rated for 50 feet, install alarms so they are evenly spaced with no more then 50 feet between devices.
  • Mount visual and audible devices 80 inches above the highest floor level within the space or six inches below the ceiling, whichever is lower.
  • Manually activated devices for use in conjunction with alarms must also be:
    Unobstructed, conspicuous, and readily accessible. 1910.165(e) Make available an emergency communications system such as a public address system, telephone, portable radio unit, or other means to notify employees of the emergency and to contact local law enforcement, the fire department, and others. 1910.165(b)(4)


Emergency response plan
For an alarm system to be effective, you must have an emergency action plan that addresses how employees, including disabled workers, will be informed that an emergency exists and how they should respond. The alarm system must inform "all affected employees" that an emergency exists and what their immediate response should be based on the alarm sequence. This plan should include:
  • How and what warning(s) will be provided through the employee alarm system for necessary emergency action as called for in the emergency action plan, or for sufficient reaction time to allow the safe escape of employees from the workplace or the immediate work area, or both; 1910.165(b)(1)
  • Procedures for sounding emergency alarms in the workplace. For those employers with 10 or fewer employees in a particular workplace, direct voice communication is an acceptable procedure for sounding the alarm provided all employees can hear the alarm. Such workplaces do not need a back-up system. 1910.165(b)(5)
  • A current list of key personnel, such as the plant manager or physician, in order of priority, to notify in the event of an emergency during off-duty hours.


Employee Alarm Systems
 Comments
check box Is the emergency preparedness plan reviewed and revised periodically?  
  Does each employee know the following?  
check box How to report an emergency  
check box The type and meaning of each emergency alarm or signal
Use distinct signals if the employee alarm system is used for alerting fire brigade members, or for other purposes; 1910.38(a)(3)(ii)
check box Evacuation routes  
check box Assembly areas  
check box First aid / medical kit locations  
check box Alarm pull box locations  
  Are the following emergency phone numbers posted?  
check box Local fire department  
check box Hospitals and ambulances  
check box Police departments  
check box Emergency response team  
check box Emergency agencies  
check box Is the employee alarm system recognizable and perceptible in all areas during emergency conditions?  
check box Are employee alarm systems properly maintained and tested regularly?  




Maintenance and testing
Employee alarm systems are important life safety devices and must be maintained in an operating condition at all times except during repairs or maintenance. 1910.165(d)(1).

Routine Test and Maintenance
  • Test the reliability and adequacy of non-supervised employee alarm systems every two months. Use a different actuation device in each test of a multi-actuation device system. 1910.165(d)(2)

  • Maintain or replace power supplies as often as necessary to ensure a fully operational condition. Provide a back-up means of alarm when systems are out of service. 1910.165(d)(3)
  • The servicing, maintenance, and testing of employee alarms must be done by properly trained persons. 1910.165(d)(5)

  • Do a visual check to ensure that employee alarm devices are not obstructed/installed in a manner that would prevent sound or light from reaching or entering the protected areas.
  • Restore all employee alarm systems to normal operating condition as soon as possible after each test or alarm. Spare alarm devices and components must be readily available. 1910.165(c)(2)

  
Employee training and education
Fire Emergency Alarm Employees must know what types of emergencies may occur and what course of action they must take. Make sure all your employees understand the function and elements of your emergency action plan, including types of potential emergencies, reporting procedures, alarm systems, evacuation plans, and shutdown procedures. Discuss any special hazards your workplace may have such as flammable materials, toxic chemicals, radioactive sources, and/or water-reactive substances. Your training should address the following:
  • Individual roles and responsibilities;

  • Threats, hazards, and protective actions;

  • Location and operation of manually activated pull stations and communication equipment;

  • Emergency response procedures;

  • Evacuation, shelter, and accountability procedures;

  • Location and use of common emergency equipment; and

  • Emergency shutdown procedures.

When your employees know how to sound an alarm and/or notifying emergency personnel at the first sign of an emergency, it may make the difference between life and death.


Workplace Evaluation | Emergency Action Plan | Expert Systems | Additional Assistance | Site Map
eTools Home : Evacuation Plans and Procedures Viewing / Printing Instructions | Credits
 
Back to Top Back to Top www.osha.gov www.dol.gov
Contact Us | Freedom of Information Act | Customer Survey
Privacy and Security Statement | Disclaimers
Occupational Safety & Health Administration
200 Constitution Avenue, NW
Washington, DC 20210