Academy of Laser Dentistry

Signs of Change
Raminta Mastis, DDS, FAGD, MALD, St. Clair Shores, Michigan
J Laser Dent 2011;19(3):301-302
Raminta Mastis, DDS, Laser Safety
Committee Chairwoman
The proper display of signs is an
essential element in implementing
a successful laser safety program in
the workplace. Since many lasers,
when active, are invisible, they
pose a potentially hazardous environment.
Even small amounts of
laser light can cause permanent
eye injuries or skin burns. Signs
serve an important function in
identifying hazards, and in giving
directions for appropriate precautions,
warnings, and protection. The
purpose of this article is to provide
guidelines specified in ANSI
Z136.1-2007 American National
Standard for Safe Use of Lasers for
signs in order to properly warn
people of the potential laser-related
health hazards in your workplace.
In a dental laser treatment
setting there are two main types of
signs: equipment labels and area
warning signs. Equipment labeling
is primarily the responsibility of
the manufacturer. Dental lasers
sold in the USA must achieve U.S.
Food and Drug Administration
(FDA) marketing clearance, which
includes the permanent affixing of
various warning and information
labels on the laser equipment itself.
The operator and Laser Safety
Officer (LSO) should be aware of
these and understand their meanings.
These labels identify
protective features and potential
hazards if the laser is tampered
with. Equipment labels also iden-
tify the class of laser and degree of
hazards. The LSO should inspect
these labels to assure that they are
intact, legible, securely affixed, and
document such inspections in a
logbook or an annual checklist. If a
label becomes illegible or comes off,
the manufacturer should be
contacted for a replacement label.
Since area warning signs are
used to indicate a change of environment,
they demand more daily
attention in order to serve the
purpose of safety. Area warning
signs are the responsibility of the
LSO and/or the delegated team
members. The appropriate uses for
these signs of change are addressed
in ANSI 136.1-2007, Section 4.7.
Area warning signs are used to
control areas where lasers are being
used. In general, signs for Class 2
and 2M lasers will have the signal
word “Caution,” and will typically be
yellow. Signs for Class 3R, 3B, and 4
lasers will use the signal word
“Danger,” and will be in red. Most
manufacturers provide a preprinted
warning sign with the pertinent
information (type of laser, emitted
wavelength, pulse duration,
maximum output, laser class, and
special precautionary instructions
and protective actions) for use by the
operator. Additional signs can be
requested from the manufacturer,
photocopied, or downloaded from the
Internet (paper copy, which you may
want to laminate), or purchased
from various companies or Web sites
that offer laser safety signs (usually
plastic), such as Laser Institute of
America (www.lia.org).
The regulations require that
these area warning signs be
conspicuously displayed before the
entry into the controlled area,
which is determined by the specific
laser’s Nominal Hazard Zone
(NHZ). The regulations also require
L A S E R S A F E T Y
that these signs be covered or
removed when the laser is effectively
taken out of operation (which
should be interpreted as laser shutdown
and not just placed in
standby mode). Most dental lasers
are designed to be portable,
meaning that they can be used in
several treatment areas throughout
the day. If the laser is moved to
different locations (i.e., multiple
treatment areas), the signs should
be changed to clearly indicate
where and when a laser is in use in
order to appropriately warn at all
entries into the NHZ.
Accidents happen, often when
they are least expected. A trained
and experienced skydiver is more
likely to sprain his ankle by tripping
on a rug or a stair in his own
home than from jumping from a
perfectly good airplane over a mile
off the ground, while being
suspended by a strip of fabric (parachute).
The same analogy can be
applied in the dental office. Be
prepared for the unexpected. Be
alert to your environment. Be aware
of the stray traffic near the NHZ.
Traffic control within hazard
zones should be managed with
clear and standard operating procedures.
It is the responsibility of the
staff to manage stray traffic (such
as a concerned parent “peeking
in”). The staff should also be
trained to recognize that interruptions
for “just a quick question” are
inappropriate during laser procedures.
It is recommended that
other forms of inter-office communications,
such as text-messaging
systems, be included in the standard
operating procedures.
In addition to the appropriate
display of Caution and Danger
signs, there is a third type of sign
defined by ANSI to identify a
Temporary Laser Controlled Area.
Mastis
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