|
|
TITLE: |
||
|
|
|||
|
DOCUMENT ID: |
3220 Appendix T1 Standardized Hazard Warning Signs & Devices |
||
|
|
|||
1.0
Introduction
Rapid identification and warning of potential hazards to personnel
is important – especially for people who do not routinely work in the area. Information signs, placards, and warning
lights/beacons are commonly used to alert visitors,
building occupants, emergency-response personnel, operations staff,
security, and utilities personnel to actual and potential hazards. It is a Lab obligation that everyone at
Jefferson Lab has consistent readily available information concerning hazards
in the workplace.
This appendix establishes the basic Jefferson Lab guidelines for
the use of hazard-information devices at facilities and workplaces that present
significant hazards to personnel or property.
Such conditions include, but are not limited to, areas which contain
flammable materials, toxic or cryogenic
material, radioactive
material, lethal electrical sources, x-rays, lasers, and
other potentially hazardous
materials and equipment.
This appendix covers:
- When hazard warning
signs are needed
- Information on
effective safety
sign content
- Requirements for use
and safety
sign design at Jefferson Lab
- Where to find specific
information required for signs
- Colors for signs and
beacons
- Where to get signs
Many topical chapters in the ES&H Manual have specific information about signs and other hazard warning devices, in particular the content of the message. This appendix is meant to compliment that information, not supersede it.
2.0
Hazard
Avoidance
Pause as you enter buildings or work areas to look for safety-information signs. Read them, and if you are unsure what they mean or how they affect you, find someone who can assist. The area safety warden is often the best choice. Rule of thumb: “If you're not sure, don't go in.”
Signs can and do change at Jefferson Lab as conditions and activities evolve. The fact that you have entered or worked in an area in the past does not guarantee that there are no new hazards or requirements.
Fulfill your responsibility for posting and maintaining hazard awareness information for your activities and work area. This includes modifying or removing signs that are out-dated or no longer applicable. Avoid creating “information clutter” and unnecessary sign proliferation.
3.0
General requirements for all safety
signs, placards, beacons, and audible devices
3.1
Hazard
signs must be posted whenever:
·
A hazard exists and a
posting requirement is identified in the ES&H Manual (i.e. radiation
controlled
areas, high noise areas, areas where high power lasers are in
use)
·
There is a temporary
change in routine conditions such as:
o A subcontractor has set-up work that could lead to an injury such
as trip, fall, or startle reaction
o
Work activity has caused
temporary blocking of normal egress
3.2
Sign
Placement
3.2.1
Locate signs to alert
and inform employees
of hazards in sufficient time to avoid the hazard and take appropriate action. Employees
should not be in harm's way before seeing the sign.
3.2.2
Signs must be placed
so that they are legible, do not create a distraction, and are not a hazard in
themselves: for example, low-hanging or protruding into a walkway. Also, signs should have rounded corners, be
free of burrs and splinters, and the fasteners have no protruding parts that
could cause abrasions or lacerations.
3.2.3
Avoid placing a sign
on a moveable object or adjacent to moveable objects like wheeled equipment,
removable partitions, etc., which if moved will obscure the sign.
3.2.4
Where illumination
may be necessary under emergency conditions, the signs should be equipped with emergency
(battery operated) illumination, luminescent or both.
3.3
Sign
Size
Overall sign size is governed by
the size of the letters and graphics.
Letters must be as large as
possible for the intended viewing distance.
Minimum letter height for the signal
word (Danger, Caution, Notice, etc.) shall be one unit of height for every
150 units of safe viewing distance.
Example: 25 feet (300 inches) safe-approach
distance -> 2-inch signal-word
letters.
Minimum letter height for other
words on the sign shall be one unit of height for every 300 units of safe
viewing distance (ANSI Z535.2-2002).
Example: 25 feet approach -> 1-inch
message letters
3.4
Hazard
alert lights (and in some situations audible warning devices) are required:
·
In specified hazard
areas as needed to warn personnel against remaining in or entering a hazardous
area.
·
For transient
conditions where a sign alone may be insufficient to attract attention. (The exclusion area beneath a crane lift, for
example.)
·
The alert light and
accompanying sign identifying the hazard must be on or adjacent to the final
barrier that an employee
would encounter when approaching a hazard.
·
The alert light must
reflect the status of equipment or a hazardous condition inside the barrier.
3.4.1
Jefferson
Lab’s alert light/beacon designations
RED identifies danger and
indicates personnel entry is not allowed.
If entry is forbidden solely due to the presence of radiation hazards,
only a magenta warning light/beacon will be required.
YELLOW is the standard color for
caution situations limiting free access of personnel and warning them to be on
the alert. (ex. Laser Controlled
Areas)
BLUE designates Oxygen Deficiency
Hazard (ODH) alarms resulting from cryogenic
release.
MAGENTA indicates the operation of radiation
producing equipment, which does not operate continuously, and reinforces the
posting of radiation warning signs in areas where they may not be posted
continuously.
3.4.2
Information
Content of Hazard Signs
The
wording on any sign should be concise and easy to read. To be effective, a sign (as opposed to a
simple decal or placard) should convey three essential pieces of information:
·
clear definition of
the hazard
·
the target organ
and/or adverse effect that the hazard presents
·
a means of avoiding
(mitigating) the hazard
Keep
sign verbiage to the minimum that conveys the message. Graphics and symbols are generally more
effective than text to draw attention to a hazard and provide the key avoidance
information.
The
eight general types of safety
signs are:
|
1. DANGER |
5. Safety Instructions |
|
2. WARNING |
6. Fire Safety: alarm and suppression
equipment location |
|
3. CAUTION |
7. Directional Arrows |
|
4. NOTICE |
8. Special Purpose Signs |
The
first four types of safety
signs use a signal
word or words to designate a level of hazard seriousness. Numbers 5 and 6 may include a signal
word. Signal
words are not used for directional arrow and special-purpose signs.
Signal words
are the word or words that designate a degree or level of safety alerting. The specific signal
words are listed in the table below.
Jefferson Lab follows the ANSI Standard Z-235 definitions and formats.
DANGER indicates an imminently hazardous situation, which,
if not avoided, will result in death or serious injury.
The choice of word and the format of the sign both
contribute to the consistent comprehension of the message. The signal
word or words shall always be located in a distinctive panel located in the
uppermost portion of the safety
sign.
3.4.3
“System-related”
safety
signs at Jefferson Lab
Some
hazards and hazardous areas at Jefferson Lab are identified via a set of signs
that describe incremental degrees of risk and progressively more robust
protective measures that are required.
Examples include:
radiation signs: For radiation hazards the signs shall display the words
Caution - Radioactive Material,
Caution - Radiation Area,
Danger - High Radiation Area,
Grave Danger - Very
High Radiation Area
Depending upon the radiological conditions. The signs shall also display the radiation symbol, a three bladed disc. All markings should be magenta on a yellow background. The posting and classification of any areas for radiation control purposes may only be done under the direction and authority of the Radiation Control Group.
Oxygen deficiency
hazard signs: degree of hazard from
0 (least) to 4 (greatest)
3.4.4
Specific features for safety
signs in common use at Jefferson Lab:
Tables
1 and 2 describe the content and applications for signs in use at Jefferson Lab. It is important to follow these requirements
to ensure the desired response.
Table 2: Examples of signs that convey or refer to
procedures
|
Class 3b and class-4 laser areas
or enclosures |
|
|
|
|
|
|
|
4.0
Pipe
& Utility Marking Systems
4.1
Piping systems
for liquids and gases
There is an industry convention for identifying piping systems according to their contents. Jefferson Lab shall install new piping with labeling that meets the requirements below.
Existing pipe identification shall be upgraded to these standards whenever it is extensively modified (re-insulated, for example).
Piping that contains substances that could present a hazard as a consequence of a credible component failure or procedural error shall be relabeled in the time frame customary for Risk Code 2 corrective actions.
Slip-on labels are acceptable for short and long-term pipe markings.
|
PIPE MARKINGS Based
upon ANSI A13.1--Standard for the Identification of Pipes |
|
|
Material
Properties |
Letter
Color on Field Color |
|
Inherently
Hazardous Materials |
|
|
Extreme Pressure or Temperature Radioactive Corrosive or Caustic Toxic or Creates Toxic Gas Explosive
or Flammable |
|
|
Low-Hazard
Materials |
|
|
Liquid
or Liquid Mixture |
|
|
Gas
or Gaseous Mixture |
|
|
Materials
for Fire Suppression |
|
|
Sprinkler
Water, Carbon Dioxide, Foam, Halon, etc. |
|
|
Outside Pipe
Diameter (Including Covering) |
Minimum
Length of Label Field Color |
Minimum
Height of Letters |
|||
|
Inches |
mm |
Inches |
mm |
Inches |
mm |
|
3/4 to 1 1/4 |
19 |
88 |
203 |
1/2 |
13 |
|
1 1/2 to 2 |
38 |
12 |
203 |
3/4 |
19 |
|
2 1/2 to 6 |
64 |
24 |
305 |
1 1/4 |
32 |
|
8 to 10 |
203 |
32 |
610 |
2 1/2 |
64 |
|
Over 10 |
Over 254 |
88 |
813 |
3 1/2 |
89 |
4.1.1
Position pipe markings:
·
Near valves, flanges,
and changes in pipe direction.
·
At both sides of
ceiling, wall, or floor penetrations.
·
At any line entry
point.
·
At frequent intervals
on straight pipe runs; every 50 feet is typical.
·
So they are visible
from the point of normal approach.
·
With arrows at one or
both ends of the label to indicate direction of flow.
4.2
Marking of
concealed utilities
Jefferson
Lab contracts directly or indirectly for location of buried or concealed
utilities prior to digging or blind penetration into walls and floors. The color-marking scheme used is recommended
by the American Public Works Association (APWA).
Table 3: APWA Uniform Color Code
Small
flags, painted symbols, lines, arrows and other markings on the ground or on
floors and walls indicate that utilities have been located, and special
precautions will be employed as the area is disturbed.
4.3
Where to get the signs
Most
signs and labels - “stock” and custom - are available from the Safety Lab. Several of the E-Commerce vendors through the
Jefferson Lab Stockroom ordering system carry selections of safety
signs. Be sure to select signs that
are consistent with Jefferson Lab's standard sign formats and content.
Signs
can also be:
·
made by the
responsible supervisor or employee
·
ordered by the area safety warden
·
Division ESH&Q staff also
have some sign-making capabilities
|
|
ISSUING
AUTHORITY |
APPENDIX
AUTHOR |
APPROVAL
DATE |
EFFECTIVE
DATE |
EXPIRATION
DATE |
REV. |
|
|
|
|
ESH&Q Division |
08/05/05 |
08/05/05 |
08/05/08 |
1 |
|