T. 3-31-93

                                                APR 15, 1993


John C. Fannin III
President
Fire Protection Electronics, Inc.
2106 Silverside Road
Wilmington, Delaware 19810

Dear Mr. Fannin:

        This letter responds to your request for information
regarding the application of the Department of Justice's
standards for accessible design under the Americans with
Disabilities Act (ADA) to installation heights for visual alarm
devices.

        The ADA authorizes the Department of Justice to provide
technical assistance and information to individuals and entities
who have questions about the Act. This letter provides informal
guidance to assist you in understanding and complying with the
ADA's standards for accessible design. However, this technical
assistance should not be viewed as legal advice or a legal
opinion about your rights or responsibilities under the ADA.

        You requested clarification of section 4.28.3 (6) of the
standards for accessible design, found at Appendix A to the
Department of Justice's regulation. This section provides
technical requirements for the visual components of alarms and
alarm systems. Specifically, this provision requires that the
visual appliances of the alarm system be located 80 inches above
the highest floor level within the space or 6 inches below the
ceiling, whichever is lower. This requirement was based on data
indicating that 80 inches was the most effective height for a 75-
candela lamp. The additional requirement that the lamp of
ceiling mounted devices be below the ceiling, rather than
recessed into or flush with the ceiling, was included because the
reflection of the flash on the ceiling surface is an important
factor affecting the visibility of the visual alarm device. This
data and reasoning is explained in the enclosed technical
bulletin on visual alarms that was developed by the Architectural
and Transportation Barriers Compliance Board.


cc: Records, Chrono, Wodatch, Magagna, Harland, FOIA, Library
n:\udd\mercado\plcrtltr\fannin.ewh




01-01995

                                     - 2 -

        The standards do not constitute a strict formula for design,
nor are they intended to constrain design innovations that
provide equal or greater access. Section 2.2 of the ADA
accessibility standards, for example, expressly provides that
"[d]epartures from particular technical and scoping requirements
of this guideline by the use of other designs and technologies
used will provide substantially equivalent or greater access to
and usability of the facility." However, the ADA does not
provide for a mechanism through which the Department of Justice,
the Access Board, or any other entity may certify any specific
variation from the standards as being "equivalent." Proposed
alternate designs, when supported by available data, are not
prohibited, but in any ADA enforcement action, the covered entity
would bear the burden of proving that any alternative design
provides equal or greater access.

        We hope that the information above is of help to you.
Please feel free to contact the Public Access Section any time
you have other questions or need further information. The
Department maintains a telephone information line to provide
technical assistance regarding the rights and obligations of
individuals, businesses, agencies, and others covered or
protected by the ADA. This technical assistance is available by
calling 202-514-0301 (voice) or 202-514-0383 (TDD) between 1:00
p.m. and 5:00 p.m., Monday through Friday.

                                        Sincerely,


                                     John L. Wodatch
                                          Chief
                                  Public Access Section


Enclosure
















01-01996
The landmark Americans with Disabilities Act (ADA), enacted on July
26, 1990, provides comprehensive civil rights protections to individuals
with disabilities in the areas of employment (title I), State and local
government services (title II), public accommodation and commercial
facilities (title III), and telecommunications (title IV). Both the
Department of Justice and the Department of Transportation, in
adopting standards for new construction and alterations of places of
public accommodation and commercial facilities covered by title III and
public transportation facilities covered by title II of the ADA, have issued
implementing rules that incorporate the Americans with Disabilities
Act Accessibility Guidelines (ADAAG), developed by the Access
Board.

U.S. Architectural and Transportation Barriers Compliance Board


BULLETIN #2: VISUAL ALARMS


WHY are visual alarms required?
One American in a hundred has a severe hearing loss; nearly one in
ten has a significant loss. Those who are deaf or hard-of-hearing--a
growing percentage of our population, due largely to the growth in the
numbers of older persons--depend upon visual cues to alert them to
emergencies. A visual alarm provides them with the warning delivered
to hearing persons by an audible alarm.

Audible fire alarms have been a standard feature of building
construction since the life safety codes of the early 1900s. However,
visible signals did not appear even in accessibility codes until 1980.
Early standards required relatively dim flashing lights at exit signs--an
alarm system that was effective only along an exit route.

As accessibility, life safety, and building codes were revised, however,
they began to incorporate alarm technology that was developed for
use in schools for persons who are deaf and in factories where
ambient noise levels made audible alarms ineffective.

In passing the Americans with Disabilities Act in 1990, Congress
specifically directed the Access Board to provide greater guidance
regarding communications accessibility. Thus the ADA Accessibility
Guidelines (ADAAG) require that where emergency warning systems
are provided in new or altered construction, they must include both
audible and visible alarms that meet certain technical specifications.

WHAT are visual alarms?
Visual alarms are flashing lights used as fire alarm signals. The terms
visual alarm signal, visible signal device, and visible signaling
appliance are used relatively interchangeably within the fire protection
community; the National Fire Protection Association (NFPA) calls them
visual notification appliances. There is no practical distinction between
a visual signal and a visible signal. Although visual signals may be
used for other purposes, the type described in this Bulletin is
appropriate only for use as an emergency alarm signal.



(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF PAGE ONE)

  "The severity of hearing problems
  was strongly associated with age.
Persons 65 and older constituted 69
 percent of the population with the
  most severe hearing trouble...but
 only 8.7 percent of the population
          without hearing trouble."
     Digest of Data on Persons with
                Disabilities (1984)
                                        





(A HAND DRAWN SKETCH OF A FIRE ALARM HAS BEEN OMITTED) 






























                                          1


01-01997

There are two major categories of fire alarms:

* self-contained units, as exemplified by the single-station residential
  smoke detector unit-battery-operated or hard-wired to building
  electrical power--which produces an alarm signal at the fixture itself
  when activated by an integral sensing device, and

* building-wide systems, integrated--often zoned--alarms whose local
  signals are remotely initiated, either automatically from detectors or
  manually from pull-stations spread throughout a facility.

ADAAG requires that when either type is installed, it must have a visual
alarm component.

WHERE are visual alarms required?
Facility design is subject to State and local ordinances that may both
require and specify standards for emergency alarm systems. These
regulations--building codes, life safety codes, accessibility codes,
technical standards--are typically derived from national model codes
and standards. The requirement for an emergency alarm system in
new construction will be established by the applicable State or local
building, life safety, or fire protection regulation. ADAAG does not
mandate an emergency alarm system: its scoping provision at
4.1.3(14) simply requires that when emergency warning systems are
provided, they shall include both audible and visual alarms that
comply with 4.28.

Thus the requirement for an alarm system in a facility will trigger the
ADAAG technical specifications for alarms. ADAAG 4.1.3(14)
Accessible Buildings: New Construction requires that visual alarms be
installed if emergency warning systems are provided in a new facility.
In existing buildings, the upgrading or replacement of a fire alarm
system would also require compliance with ADAAG technical
provisions for alarms.

Where the need for a visual alarm is not predictable, as in spaces
used in common by building occupants or those generally available for
use by the public, equivalent warning must be provided to every
potential user. This is particularly important in those common use
spaces where a persons may be alone. Because it is not always
possible to fix the occupancy of a room or space or anticipate its use
by a person with a hearing impairment, every common use room or
space required to have an emergency alarm system must be served
by both audible and visible signals.

ADAAG 4.28.1 General stipulates that alarm systems required to be
accessible shall provide visible signals in restrooms, other general and
common use areas, and hallways and lobbies. Common use areas
include meeting and conference rooms, classrooms, cafeterias,
photocopy rooms, employee break rooms, dressing, examination, and
treatment rooms, and similar spaces that are not the assigned work
areas of specific employees.
Where audible alarm signal appliances are installed in corridors and
lobbies to serve adjacent public or common use rooms, individual
visual alarm signal appliances must be installed in those rooms, since

(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF PAGE TWO)

          4.1.3 (14) New Construction.                                        
      If emergency warning systems are                                        
provided, then they shall include both           
   audible and visual alarms complying           
  with 4.28. Emergency warning systems           
     in medical care facilities may be           
 modified to suit standard health care           
                alarm design practice.           


                           4.28 Alarms.          
                        4.28.1 General.          
           Alarm systems required to be                                        
    accessible by 4.1 shall comply with                                        
      4.28. At a minimum, visual signal                                        
        appliances shall be provided in                                        
buildings and facilities in each of the                                        
     following areas: restrooms and any                                        
       other general usage areas (e.g.,                                        
 meeting rooms), hallways, lobbies, and                                        
         any other area for common use.                                        

                       3.5 Definitions.                                        
                            Common Use.                                        
  Refers to those interior and exterior                                        
    rooms, spaces, or elements that are                                        
        made available for the use of a                                        
restricted group of people (for example,   
   occupants of a homeless shelter, the                                        
occupants of an office building, or the                                        
             guests of such occupants).                                        

















                                        2
01-01998
the warning provided by a visual signal, unlike that of a bell or other
annunciation system, can only be observed within the space where it
is installed. System designers and specifiers must therefore be
especially sensitive to coverage issues. Dressing, fitting, and
examination rooms for example, can be easily protected by an audible
alarm outside the room or space. However, the customer or patient
who has a hearing impairment will not be alerted unless the dressing
room he/she is using is protected with a visual alarm in (or above,
where partitions are not full height) the space. In general, it will not be
sufficient to install visual signals only at audible alarm locations.

WHERE are visual alarms not required?
ADAAG does not require that areas used only by employees as work
areas be constructed or equipped to be accessible. Thus, visual
alarms are not required in individual employee offices and work
stations. However, the provision of a visual alarm in the work area of
an employee who is deaf or hard-of-hearing may be--like other
elements of workplace accessibility--a reasonable accommodation
under title |** of the ADA, which addresses employment issues. The
potential for such future employee accommodations should be
considered when facility wiring is planned to facilitate a later
connection to the building alarm system.

Mechanical, electrical and telephone closets, janitor's closets, and
similar non-occupiable spaces that are used by employees but are not
common use facilities nor assigned work areas are not required to
have visual alarms.

WHAT technical provisions apply to visual alarms?
The technical provisions of ADAAG 4.28 Alarms include minimum
standards for the design and installation of single-station and
building-wide visual alarm systems. They are based upon research
sponsored by the Access Board and other groups, principally
Underwriters Laboratories (UL).

To be effective, a visual signal--or its reflection from adjacent walls and
ceiling--must be of an intensity that will raise the overall light level
sharply, but not so intense as to be unsafe to direct viewing at a
specified mounting height. Technical criteria for visual alarm signal
appliances are established in ADAAG 4.28.3 Visual Alarms (See sidebars).

In research sponsored by the Access Board, a high-intensity xenon
strobe lamp was found to be the most effective in alerting persons with
hearing impairments. White light was judged to be the most
discernible; colored lamps (particularly red) were not effective even at
extreme intensities. Lamp intensity is given in effective candela,
measured at the source rather than at the receiving location.

Like a camera flash, the strobe produces a short burst of high-intensity
light. The repetition of this pulse at a regular interval is the flash rate.
Pulse duration--the interval between initial signal build-up and decay,
measured across the lamp bell curve at a fixed intensity--is limited so
that the signal flash is not temporarily blinding.

In the Access Board's research, ninety percent of the subjects in
standard daylit rooms were alerted by a 75 candela signal mounted 50
                                        
(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF PAGE THREE)    

                                     
              For information on employee  
       accommodation under title I of the  
        ADA, contact the Equal Employment  
        Opportunity Commission (EEOC) ADA  
                      information line at
                    (800)669-3362 (Voice)  
                      (800)800-3302 (TDD)  

                    4.28.3 Visual Alarms.  
  Visual alarm signal appliances shall be  
 integrated into the building or facility
 alarm system.  If single station audible  
  alarms are provided then single station  
       visual alarm signals shall also be  
     provided. Visual alarm signals shall  
               have the following minimum  
       photometric and location features:  
                                      (1)
    The lamp shall be a xenon strobe type  
                           or equivalent.  
                                      (2)  
      The color shall be clear or nominal  
white (i.e., unfiltered or clear filtered  
           white light).  (see sidebars).
                                      (3)
      The maximum pulse duration shall be  
  two-tenths of one second (0.2 sec) with  
      a maximum duty cycle of 40 percent.  
     The pulse duration is defined as the  
 time between initial and final points of  
            10 percent of maximum signal.  
                                      (4)
   The intensity shall be a minimum of 75  
                                 candela.  
                                      (5)  
     The flash rate shall be a minimum of  
              1 Hz and a maximum of 3 Hz.  







                                  3

01-01999

feet away. Thus a single visual signal meeting these ADAAG
specifications could be expected to serve a large rectangular room or
a 100-foot length of corridor if optimally located in the center of the
space. Its lamp must be installed and oriented so that the signal or its
reflection can spread throughout the space. To be effective, the signal
must not be obstructed by furnishings, equipment, or room geometry.

Testing further indicated that flash rate cycles between one and three
Hertz (flashes per second) successfully alerted subjects with hearing
impairments; a 3 Hz signal appeared to be somewhat more effective.
ADAAG thus requires flash rates within the 1 to 3 Hz range. Rates that
exceed 5 Hz may be disturbing to persons with photosensitivity,
particularly those with certain forms of epilepsy. Information received
during the development of the standards suggested that multiple
unsynchronized visual signals within a single space may produce a
composite flash rate that could trigger a photoconvulsive response in
such persons. A rate in excess of 5 Hz should be avoided, either by
raising the intensity and decreasing the number of fixtures or by
synchronizing the flash rates of the fixtures. This is particularly
important in schools, since children are more frequently affected by
photosensitivity than are adults.

Mounting provisions were developed from NFPA signal criteria and UL
smoke test findings. Strobes--whether projected from a wall or
suspended from the ceiling--must be a minimum of 6 inches below the
ceiling plane and at least 80 inches above the finished floor. To
minimize the effect of smoke obscuration in the event of a fire, the
lamp itself may not be mounted directly to the ceiling.

Provisions governing the spacing of visual alarms in hallways and
corridors will generally require one fixture every 100 feet in linear
corridors and hallways; somewhat closer spacing may result in
enclosed rooms. In large-volume spaces, visual alarms may be
suspended overhead or installed on perimeter walls if sightlines are
unobstructed. In lengthy corridors, such as in shopping malls and
large buildings, it is recommended that appliance spacing be
maximized within the limits of the technical provision to minimize the
effect of a composite flash rate on persons with photosensitivity. It is
further recommended that the placement of visual signals along a
corridor alternate between opposing walls to minimize the number of
signals in a field of view.

In multipurpose facilities where bleacher seating, athletic equipment,
backdrops, and other movable elements may at times be deployed or
in warehouses and similar building types where devices would not be
visible when installed at specified heights, optimal signal placement
may require considerable study.

WHAT criteria affect the design of visual alarm systems?
Figures 1, 2, and 3 illustrate general fixture replacement and lamp
coverage in schematic form. In general, it is recommended that visual
alarm lamp intensity be maximized so as to require the minimum
number of fixtures. Large, high-ceilinged spaces may best be served
by suspended flash tubes of very high intensity (lamps up to 1000
candela are available). Smaller rooms--less than 75 feet in their
maximum dimension--can be covered by a single, centrally located
                                           
(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF PAGE FOUR)

                                      (6)  
      The appliance shall be placed 80 in  
  (2030 mm) above the highest floor level  
        within the space or 6 in (152 mm)  
   below the ceiling, whichever is lower.  
                                      (7)
      In general, no place in any room or  
   space required to have a visual signal  
       appliance shall be more than 50 ft  
           (15 m) from the signal (in the  
    horizontal plane). In large rooms and  
   spaces exceeding 100 ft (30 m) across,  
    without obstructions 6 ft (2 m) above  
  the floor, such as auditoriums, devices  
      may be placed around the perimeter,  
    spaced a maximum 100 ft (30 m) apart,  
    in lieu of suspending appliances from  
                             the ceiling.  
                                      (8)  
          No place in common corridors or  
           hallways in which visual alarm
 signalling appliances are required shall  
       be more than 50 ft (15 m) from the  
                                  signal.  
                                 Figure 1  
                     Strobe lamp coverage

                   (FIGURE OMITTED)
                   
                             Recommended  

                   (FIGURE OMITTED)
 
                          Not recommended












                                     4

01-02000
visual alarm meeting ADAAG intensity specifications. For very small
rooms, such as dressing rooms, a strobe of lesser intensity may well
be sufficient as an equivalent facilitation.

Signal intensity and placement in very small and very large rooms and
in spaces with high ceilings, irregular geometry, dark or non-reflective
walls, or very high ambient lighting levels may best be determined by
specialized consultants employing photometric calculation for system
design rather than by a literal application of ADAAG specifications. For
these reasons, ADAAG 2.2 Equivalent Facilitation permits alternative
designs that achieve substantially equivalent or greater accessibility.

Lamp intensity (like sound) decreases in inverse relation to the square
of its distance from the viewer. Thus, by varying lamp intensity and
spacing, system designers can tailor an installation to the physical
conditions of the space being served. It is impossible to provide
specific guidance for the design of non-standard installations based
upon the photometric calculations necessary to demonstrate
equivalent facilitation. Such applications should generally be designed
by experienced electrical engineers or fire alarm consultants under
performance specifications for coverage and illumination levels derived
from the technical provisions of ADAAG 4.28. As there is no process
for certifying alternative methods (except in transportation facilities
under DOT enforcement), the responsibility for demonstrating
equivalent facilitation in the event of a challenge rests with the covered
entity.

The American National Standard for Accessible and Usable Buildings
and Facilities (CABO/ANSI A117.1-1992), reflecting current NFPA
performance recommendations for visual alarms, stipulates lamp,
installation, and spacing criteria at some variance with ADAAG
technical specifications for visual alarms and with this advisory. ANSI
Table 4.26.3.2(a), Room Spacing Allocation, suggests that an alarm
installation of several low-intensity lamps within a room is the practical
equivalent of a single high-intensity lamp serving that space. Given
concerns for economy (lower-candela lamps are less expensive to
purchase and connect) and lamp standardization within a building
(lower-candela lamps are more available and simplify inventorying),
specifiers may be motivated to standardize on a minimum-candela
fixture, achieving coverage in large rooms by close spacing of low-intensity
lamps. The Access Board strongly discourages this practice.
Where a single lamp can provide the necessary intensity and
coverage, multiple lamps should not be installed because of their
potential effect on persons with photosensitivity.

WHAT types of visual alarms are available?
All major suppliers to the fire protection industry manufacture visual
signals, which are readily available to electrical contractors and others
responsible for the installation of building alarm systems. Visual
alarms incorporating smoke detectors and lamp-only signal appliances
are supplied through standard sources, although some lamp
intensities and visual alarm fixtures may not be commonly stocked.
Strobe lamps are commercially available in varying intensities up to
100 candela. Higher intensities can be provided by specialized
manufacture.
                                            
(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF PAGE FIVE)

              2.2 Equivalent Facilitation.
      Departures from particular technical  
          and scoping requirements of this  
     guideline by the use of other designs  
      and technologies are permitted where  
               the alternative designs and  
            technologies used will provide  
       substantially equivalent or greater  
  access to and usability of the facility.  
  

                                Figure 2  
          Recommended spacing in corridors  

                   (FIGURE OMITTED)


                                  Figure 3  
                     Recommended placement
           in irregular room configuration

                   (FIGURE OMITTED)

























                                    5     
01-02001

Although an integrated audible and visual signal is available at about
the same cost as an audible or visual signal alone, more visual signals
than audible signals will be necessary for most applications. Careful
attention to reflection from surfaces can increase light dispersion and
coverage in both new and renovated structures.

WHAT visual alarm requirements apply to sleeping rooms in
transient lodging facilities?
ADAAG 9.3.1 requires the installation of a visual alarm--or power outlet
for a portable device--connected to the building alarm system in the
sleeping rooms of units requires to be accessible under Section 9
Accessible Transient Lodging. Because guest room sizes are not
large in such occupancies, the technical specification of 4.28.4
Auxiliary Alarms requires only that the signal--intended to alert persons
who are awake--be visible in all areas of the room or unit. Portable
units with a standard 110 volt electrical cord can be acquired from
retailers of products for persons who are deaf and hard-of-hearing.

Visual alarms are not the technology of choice for awakening sleeping
persons, however. A UL study concluded that a flashing light more
than seven times brighter than that needed to alert office workers (110
candela vs. 15 candela at 20 feet) would be required to arouse a
person who was asleep. Alarm system designers are advised to
consider the UL findings if visual alarms are to be employed to warn
sleeping persons of emergencies.

ADAAG does not establish standards for portable items or auxiliary
aids. However, devices that employ technologies other than visual
signalling may offer equivalent or superior warning for sleeping guests
who have hearing impairments. For example, a signal-activated
vibrator was found to be much more effective in alerting sleepers than
were the visual signals tested in the UL research. Such devices are
commonly available and may be connected to or activated by a
building alarm system. Care must be taken that notification devices
intended to signal a door knock or bell are separately wired.

WHY is there an exception in the scoping requirements of
4.1.3(14) for "standard health care alarm design practice"?
In medical care settings where a supervised emergency evacuation
plan is in place, it is usually not desirable to install alarms in patient
rooms or wards. In such occupancies, personnel responsible for
ensuring the safe egress of patients will respond to an intercom
message or other signal that is not intended to alert or alarm patients
incapable of independent evacuation. The requirements for visual and
audible alarms may be modified to suit industry-accepted practices for
such facilities.


Bulletin #2                                             December 1992

U.S. Architectural and Transportation Barriers Compliance Board
The Access Board/1331 F St., NW #1000/Washington, DC 20004
TEL:(800)USA-ABLE       (202)272-5434           TDD: (202) 272-5449




(THE FOLLOWING APPEARS IN THE LEFT MARGIN OF LAST PAGE)


                  4.28.4 Auxiliary Alarms.  
         Units and sleeping accommodations  
    shall have a visual alarm connected to  
       the building emergency alarm system  
         or shall have a standard 110-volt
  electrical receptacle into which such an  
        alarm can be connected and a means  
       by which a signal from the building  
        emergency alarm system can trigger  
      such an auxiliary alarm. When visual  
   alarms are in place the signal shall be  
 visible in all areas of the unit or room.  
     Instructions for use of the auxiliary  
    alarm or receptacle shall be provided.  

           9.3 Visual Alarms, Notification  
                   Devices and Telephones.
                            9.3.1 General.  
      In sleeping rooms required to comply  
with this section, auxiliary visual alarms  
   shall be provided and shall comply with  
 4.28.4. Visual notification devices shall  
       also be provided in units, sleeping  
            rooms and suites to alert room  
     occupants of incoming telephone calls
    and a door knock or bell. Notification  
         devices shall not be connected to  
  auxiliary visual alarm signal appliances  
                                    [...].  

            9.3.2 Equivalent Facilitation.  
  For purposes of this section, equivalent  
facilitation shall include the installation 
  of electrical outlets (including outlets  
   connected to a facility's central alarm
           system) and telephone wiring in  
       sleeping rooms and suites to enable  
       persons with hearing impairments to  
        utilize portable visual alarms and  
     communication devices provided by the  
                 operator of the facility.  


     This technical assistance is intended
    solely as informal guidance; it is not
    a determination of the legal rights or
   responsibilities of entities subject to  
             titles II and III of the ADA.