foot-candle measurement

[6spdYJ]

I have an oddball question. How can I measure a value of 5 foot-candles through a green lens in a room with a highbay fluorescent light 20 feet overhead? The fluorescents are 5000k color. This isn't really a photography question, but I figured someone here could help. What I'm up against is corporate safety nazis saying an exit sign isn't illuminated - but the bulbs are on. Thanks.

[dirtman13]

You won't be able to. Exit signs don't put off that much light. From your description sound like your fluorescents are washing out the exit signs. How high are the exit signs?

[NAILER341]

Here is the code. See if any of the exceptions apply to you or have the mfr. send you info on your signs.


SECTION 1011
EXIT SIGNS
1011.1 Where required. Exits and exit access doors shall be
marked by an approved exit sign readily visible from any direction
of egress travel. The path of egress travel to exits and
within exits shall be marked by readily visible exit signs to
clearly indicate the direction of egress travel in cases where the
exit or the path of egress travel is not immediately visible to the
occupants. Intervening means of egress doors within exits shall
2010 CALIFORNIA BUILDING CODE
be marked by exit signs. Exit sign placement shall be such that
no point in an exit access corridor or exit passageway is more
than 100 feet (30480 mm) or the listed viewing distance for the
sign, whichever is less, from the nearest visible exit sign.
Exceptions:
1. Exit signs are not required in rooms or areas that
require only one exit or exit access.
2. Main exterior exit doors or gates that are obviously
and clearly identifiable as exits need not have exit
signs where approved by the building official.
3. Exit signs are not required in occupancies in Group U
and individual sleeping units or dwelling units in
Group R-1, R-2, R-3 or R-3.1.
4. Exit signs are not required where inmates are housed,
or held in dayrooms, sleeping rooms or dormitories in
occupancies in Group 1-3.
5. In occupancies in Groups A-4 and A-5, exit signs are
not required on the seating side of vomitories or openings
into seating areas where exit signs are provided in
the concourse that are readily apparent from the
vomitories. Egress lighting is provided to identify
each vomitory or opening within the seating area in an
emergency.
1011.2 Dlumination. Exit signs shall be internally or externally
illuminated.
Exception: Tactile signs required by Section 1011.3 need
not be provided with illumination.
> 1011.3 Tactile exit signs. For the purposes of Section 1011.3,
the term "tactile exit signs" shall mean those required signs
that comply with Section 1117B.5.1 Item 1. Tactile exit signs
shall be required at the following locations:
1. Each grade-level exterior exit door shall be identified by
a tactile exit sign with the word, "EXIT."
2. Each exit door that leads directly to a grade-level exterior
exit by means of a stairway or ramp shall be identified
by a tactile exit sign with the following words as
appropriate: .
A. "EXIT STAIR DOWN"
B. "EXIT RAMP DOWN"
C. "EXIT STAIR UP"
D. "EXIT RAMP UP"
3. Each exit door that leads directly to a grade-level exterior
exit by means of an exit enc?osure that does not utilize
a stair or ramp, or an exit passageway shall be
identified by a tactile exit sign with the words, "EXIT
ROUTE."
4. Each exit access door from an interior room or area that
is required to have a visual exit sign, shall be identified
by a tactile exit sign with the words, "EXIT ROUTE."
5. Each exit door through a horizontal exit shall be identified
by a tactile exit sign with the words, "TO EXIT. "
2010 CALIFORNIA BUILDING CODE
MEANS OF EGRESS
1011.4 Internally illuminated exit signs. Electrically powered,
self-luminous and photoluminescent exit signs shall be
listed and labeled in accordance with UL 924 and shall be
installed in accordance with the manufacturer's instructions
and Chapter 27. Exit signs shall be illuminated at all times.
1011.5 Externally illuminated exit signs. Externally illuminated
exit signs shall comply with Sections 1011.5.1 through
1011.5.3.
1011.5.1 Graphics. Every exit sign and directional exit sign
shall have plainly legible letters not less than 6 inches (152
mm) high with the principal strokes of the letters not less
than 3/4 inch (19.1 mm) wide. The word "EXIT" shall have
letters having a width not less than 2 inches (51 mm) wide,
except the letter "I," and the minimum spacing between
letters shall not be less than 3/8 inch (9.5 mm). Signs larger
than the minimum established in this section shall have
letter widths, strokes and spacing in proportion to their
height.
The word "EXIT" shall be in high contrast with the background
and shall be clearly discernible when the means of
exit sign illumination is or is not energized. If a chevron
directional indicator is provided as part of the exit sign, the
construction shall be such that the direction of the chevron
directional indicator cannot be readily changed.
1011.5.2 Exit sign illumination. The face of an exit sign
illuminated from an external source shall have an intensity
of not less than 5 foot-candles (54 lux).
1011.5.3 Power source. Exit signs shall be illuminated at all
times. To ensure continued illumination for a duration of not
less than 90 minutes in case of primary power loss, the sign
illumination means shall be connected to an emergency
power system provided from storage batteries, unit equipment
or an on-site generator. The installation of the emergency
power system shall be in accordance with Chapter 27.
Exception: Approved exit sign illumination means that
provide continuous illumination independent of external
power sources for a duration of not less than 90 minutes,
in case of primary power loss, are not required to be connected
to an emergency electrical system.
1011.6 Floor-level exit signs. Where exit signs are required by
Chapter 10, additional approved low-level exit signs which are
internally or externally illuminated photoluminescent or
self-luminous, shall be provided in all interior corridors of
Group A, E, I and R-2.1 occupancies and in all interior rated II
exit corridors serving guest rooms of hotels in Group R, Division
1 occupancies.
Exceptions:
1. Group A occupancies that are protected throughout
by an approved supervised fire sprinkler system.
2. Group E occupancies where direct exits have been
provided from each classroom.
3. Group I and R-2.1 occupancies which are provided
with smoke barriers constructed in accordance with
Section 407.4
4. Group 1-3 occupancies.
345
II
MEANS OF EGRESS
The bottom of the sign shall not be less than 6 inches (152
mm) or more than 8 inches (203 mm) above the floor level and
shall indicate the path of exit travel. For exit and exit-access
doors, the sign shall be on the door or adjacent to the door with
the closest edge of the sign or marker within 4 inches (102 mm)
of the door frame.
Note: Pursuant to Health and Safety Code Section 13143,
this California amendment applies to all newly constructed
buildings or structures subject to this section for which a
building permit is issued (or construction commenced,
where no building permit is issued) on or after January 1,
1989.
1011.7 Path marking. When exit signs are required by Chapter
10, in addition to approved floor-level exit signs, approved
path marking shall be installed at floor level or no higher than
8 inches (203 mm) above thefloor level in all interior rated exit
corridors of unsprinklered Group A occupancies, and Group
R-1 and R-2 occupancies.
Such marking shall be continuous except as interrupted by
door-ways, corridors or other such architectural features in
order to provide a visible delineation along the path of travel.
Note: Pursuant to Health and Safety Code Section 13143,
the California amendments of this section shall apply to all
newly constructed buildings or structures subject to this
section for which a building permit is issued (or construction
commenced, where no building permit is issued) on or
after January 1, 1989.

[6spdYJ]

Thanks, my first reaction to my HR was to tell them to pull their heads out and it would be easier to see the light.

[daniel_buck]

if you have a narrow spot meter, you could figure it out relative to other light intensities.

[6spdYJ]

Nah, all I have are narrow-minded inspectors. I was just wondering if there was a way to ballpark this thing. Mostly it's a principal issue. I inspect them and repair them on a monthly basis. They came in for an annual audit, didn't like their foo-foo coffee or whatever and dinged us on our corporate review while trying to make it look like I haven't done my job. I get a little bitter about such things... I guess I'll just have to order all new lighting and put the inspector's name on the justification. Sorry, rant over.