THE UNIVERSITY OF TENNESSEE
AGRICULTURAL EXTENSION SERVICE
AS-01-94
(rev 10/97)
Eye Safety on the Farm
Timothy G. Prather
Assistant Extension Assistant
Agricultural and Biosystems Engineering Department
An estimated 7,500 eye injuries occur on American
farms annually. These injuries are painful, expensive and
can result in partial or total blindness.
Human eyes are tough and have a certain degree of
natural protection, but this natural protection is no match
for chemicals or high-speed objects that may be hurled at
them during farm and shop operations. Eye protection is
needed in many daily farm activities, even when machinery
and chemical safety steps are carefully followed and
equipment is kept in good repair.
Farmers often wear eye protection for certain tasks, yet
many needless eye injuries still occur because they do not
wear eye protection during all potentially hazardous
operations.
You can reduce your chances of having an eye injury.
Good eye protection habits are easy to acquire. In fact, eye
safety on the farm is as simple as "one, two, three. . ."
1. Know the hazards
Most farm eye injuries occur in the course of regular
farm work and during common activities where dust
particles, flying objects and chemical spray are expected
elements in the work environment. Activities where eye
injuries may occur include harvesting, haying and other
field jobs involving dust, chaff or other flying pieces;
grinding, drilling, sawing, welding and other farm shop
jobs; lumbering, orchard work, or trimming trees;
operating, maintaining and repairing farm machinery;
spray painting; and handling and applying agricultural
chemicals.
2. Select the proper safety eyewear
Different eye protection equipment is needed for
different tasks. Eye protection should be selected on the
basis of protection from a particular hazard.
Safety glasses provide moderate
frontal protection against flying
particles. All prescription corrective
lenses are by law impact-resistant;
however, "impact-resistant" does not mean
shatterproof. Safety glasses with lenses and frames
meeting industrial safety lens standards offer greater
protection. Close-fitting safety glasses with browguards
and side shields offer better protection than plain
spectacles. NOTE: Always wear safety goggles in addition
to safety glasses when the possibility of heavy impact or
chemical splash exists.
Goggles offer both frontal and side
protection, with excellent protection
against most flying particles. They
may be worn over regular glasses.
Splash goggles with shielded vents offer
excellent protection from chemical splashes, while
unvented goggles should be worn when handling dangerous
chemicals, such as anhydrous ammonia. Chipping goggles,
with individual eye cups, offer maximum impact protection
and are also recommended for use in extremely dusty
activities.
Face Shields are primarily for splash
protection when working with chemicals
and are intended to be worn over other
protectors. Although they offer some
protection against small flying particles,
they are not made for heavy impact. When
working with chemicals that are extremely dangerous to
your eyes, like anhydrous ammonia, unvented goggles as
well as face shields are recommended.
Welding goggles and shields with
special absorptive or filter lenses provide
protection against dangerous ultraviolet
and infrared radiation, sparks, flying
particles and other welding hazards. A
welding helmet with a flip-up lens backed
by a clear lens is very convenient and offers excellent
protection during welding and chipping operations.
Magnifying lenses are also available to help see the work
better. Always wear goggles under welding helmets.
Sunglasses are important protection for the farmer who
works for prolonged periods out-of-doors as protection
against the sun's harmful rays. DO NOT use ordinary
sunglasses for impact protection or for protection against
radiation from cutting and welding operations! You can
obtain tinted lenses for safety glasses, goggles and face
shields to protect you from bright sunlight, however.
The lenses in eye protective devices should offer clear,
comfortable vision without noticeable distortion. Eye
protection devices should fit snugly and correctly. Straps,
frames and other parts should be durable and fit
comfortably. When selecting welding glasses, consult your
welding supply dealer on the shade of filter lens needed for
the type of welding you do.
All protective eyewear must meet ANSI Z87.1
standards. This will be indicated on the packaging as well
as on the eyewear itself. This approval is your assurance
that the lenses and frames can withstand a certain amount
of impact without failure. Basic requirements of ANSI
Z87.1 are minimum lens thickness (3 mm for glass lenses,
2 mm for plastic lenses), lenses must pass impact testing,
the frames must withstand certain strength tests and frames
must not permit the lenses to be forced out toward the rear.
•
Acetate has excellent chemical resistance and is
primarily used in faceshields. Impact and heat
resistance is not as good as polycarbonate.
•
Glass has excellent chemical and scratch resistance.
Glass lenses are available in various tint styles and
may absorb over 99 percent of the UV light. Hot
metal adheres to and invariably shatters glass lenses.
Glass lenses are heavier and have lower shatter
resistance than polycarbonate.
•
Polycarbonate is the most common lens material
today and is available in a wide variety of styles and
tints. It is a plastic with good chemical resistance
and excellent impact resistance (it may break, but
does not shatter). Because polycarbonate is much
lighter than glass and absorbs over 99 percent of UV
light, it can be worn for outdoor activities
comfortably for extended periods. The main
disadvantage of polycarbonate is that it scratches
more easily than glass.
•
Wire mesh face shields are a good choice for some
activities, such as operating string trimmers and
chainsaws, but must be worn over safety glasses or
goggles. The mesh offers protection from small
flying objects, but minimal protection from hard
impact and no protection from chemicals and dusts.
The advantage of wire mesh is that it has excellent
ventilation and does not fog and or scratch.
Lens tints: The tint you select for your safety eyewear
is as important as the lenses themselves. Select the tint that
provides the protection you need with the least eye strain.
•
Clear lenses are best for indoor and general use.
Color perception is not affected by clear lenses.
•
Gray lenses are good for work outdoors or in other
very bright locations, and are available as solid gray
or gradient tint (dark at top and almost clear at the
bottom). Gray lenses do not affect color perception.
•
Green - Generally used for protection against
infrared radiation from hot work (welding, brazing,
cutting, glassblowing, etc.), with the shade used
depending upon type work being performed.
•
Amber or yellow - increases contrast under certain
lighting conditions, such as hazy or very overcast
weather, but seriously alters color perception
(objects will appear either yellow or black).
•
Mirrored - Usually used on lenses for outdoor wear
to help reduce glare. Sometimes reflective coatings
are used on lenses for welding, but the lenses must
be of the proper shade for the job.
•
Polarized - Polarized lenses are not common in
industrial safety glasses, but can be found in quality
sporting eyewear meeting ANSI Z87.1 standards.
Polarized lenses reduce glare from nonmetallic
surfaces and make colors appear richer. They are
excellent for outdoor use, especially driving and
water sports.Laser safety glasses - Lasers are
especially harmful to eyes because the light is
focused in such a small beam and the retina is
burned very quickly (much like focusing sunlight
with a magnifying glass to burn paper). Glasses or
goggles for laser use are specific to the type laser
being used. NEVER look into a laser beam!
the vision you need for safe, efficient farming.
3. Wear safety eyewear - always
The best eye protection devices made are useless if they
are in your pocket or dangling from a machine at the time
of an injury. You should know how and when to use eye
safety devices - and use them. Wear them routinely
whenever even the slightest possibility of an eye injury
exists.
Two of the more common complaints about protective
eyewear are that it is uncomfortable and problems with
fogging. Discomfort can be reduced by selecting the most
comfortable safety glasses or goggles possible (they cost
about the same as the least comfortable ones). Fogging
results when warm, humid air contacts cool lenses.
Wearing your safety glasses all the time will keep them
warm and eliminate most fogging problems. Anti-fog
coatings on the lenses also help.
Keeping your vision up to par will also help reduce eye
injuries and other farm mishaps. You can't avoid hazards
if you can't see them. Periodic vision examinations will aid
in the early detection of eye disease and help you maintain
You can reduce the possibility of an eye injury on your
farm, it's as simple as "one, two, three ..."
References:
"Eye Safety of the Farm", American Optometric
Association, 7000 Chippewa Street, St. Louis, Missouri
63119.
Fundamentals of Industrial Hygiene, Third Edition.
1988. National Safety Council, 444 North Michigan
Avenue, Chicago, IL 60611-3991. pp 77-92.
Vallen Safety Supply Company, 1992 Safety Catalog.
Vallen Safety Supply Company, 13333 Northwest Freeway,
Houston, TX 77040-6086. pp 112-113, 131.
OSHA Standards for General Industry, 29 CFR
1910.252(e)(2)(i). US Department of Labor.
OSHA Standards for Welding, Cutting and Heating
(draft of revisions). 29 CFR 1926.351. US Department of
Labor.
Safety in Welding and Cutting. ANSI/ASC
Z49.1-1983. Amercan National Standards Institute.
CHOOSING EYE AND FACE PROTECTION
Use the accompanying charts to select protective devices based on the hazards to be encountered. The Selection Chart
offers general recommendations only. Final selection of eye and face protection is the responsibility of management and
safety specialists.
For maximum user acceptance, select the most comfortable and best looking protective eyewear that is suitable for the tasks
and hazard exposures.
Always remember that eye and face protection devices DO NOT provide unlimited protection.
NOTES:
1. Always consider the possibility of multiple and simultaneous exposure to a variety of hazards. Select protection based
on the most severe hazard.
2. Activities involving heat may also involve optical radiation hazards. Protection from both hazards must be provided.
3. Faceshields must only be worn over primary eye protection.
4. Filter lenses for cutting, welding and heating operations must meet the shade requirements in Table 2.
5. Persons requiring prescription (Rx) lenses must wear either protective devices fitted with prescription lenses or designed
to be worn over prescription lenses.
6. Contact lens wearers must wear appropriate covering eye and face protectors in a hazardous environment. It should be
recognized that dusty and/or chemical environments may present an additional hazard to contact lens wearers.
7. Use caution when wearing metal framed eyewear in electrical hazard areas.
8. Refer to section 6.5 (Special Purpose Lenses) of ANSI standard Z87.1.
9. Welding helmets or handshields must be used only over primary eye protection.
10. Spectacles without sideshields are available for limited hazard use requiring only frontal protection, but are not
recommended.
TABLE 1. EYE PROTECTION SELECTION CHART
Activity
Activity
I
M
P
A
C
T
H
E
A
T
C
H
E
M
I
C
A
L
D
U
S
T
Chipping,
grinding,
machining,
masonry work,
riveting, sanding
Furnace
operations,
pouring, casting,
hot dipping,
cutting, welding
Protector
type
Hazards
Flying fragments,
objects, large chips,
particles, sand, dirt,
etc.
B, C, D, E, F, G,
H, I, J, K, L, N
Spectacles, goggles,
faceshields.
See Notes 1, 3, 5, 6, 10.
Hot sparks
B, C, D, E, F, G,
H, I, J, K, L, N
Faceshields, goggles,
spectacles.
For severe exposure
see Notes 2 & 3.
Splash from molten
metals
N
Faceshields worn over
goggles H, K.
See Notes 2 & 3.
High temperature
exposure
N
Screen faceshields.
Reflective faceshields.
See Notes 2 & 3.
G, H, K
Unvented or indirectly
vented goggles, eyecup
and cover types.
Splashes
Acid and
chemicals
handling,
degreasing,
plating.
N
Irritating mists
Woodworking,
buffing, general
dusty conditions
Protectors
Nuisance dusts
G
G, H, K
For severe exposure,
add faceshield
Limitations
Protective devices do
not provide unlimited
protection.
See Note 7
Spectacles, cup and
cover type goggles do
not provide unlimited
facial protection.
Not
Recommended
Devices without
protection from side
exposures.
Filter or tinted lenses
that restrict light
transmission, unless
it is determined that a
glare hazard exists.
Refer to Optical
Radiation.
Devices without
protection from side
exposure.
See Note 3.
Ventilation should be
well protected from
splash entry.
Special purpose
goggles.
See Note 3.
Goggles, eyecup and
cover types
Atmospheric conditions
and the restricted
ventilation of goggles
can cause lens to fog.
Frequent cleaning may
be required.
Spectacles, welding
helmets, handshields.
Electric arc welding
O
P
T
I
C
A
L
R
A
D
I
A
T
I
O
N
O, P, Q
See Note 9.
Welding helmet or
welding shield.
Lens shade 10-14.
See Note 9.
Welding helmet or
shield.
Lens shades:
Gas torch cutting and welding
Welding
J, K, L, M, N,
O, P, Q
3-6
Refer to Table 2.
Torch brazing
Glare
Lasers
4-8
See Note 3.
Cutting
Torch soldering
Protection from optical
radiation is directly
related to filter density.
Select the darkest
shade that allows
adequate vision and
task performance.
See Note 4.
Refer to Table 2.
3-4
B, C, D, E, F, N
Spectacles or welding
faceshield.
Lens shade 1.5-3.
A, B
Spectacle.
See Notes 9 & 10.
Shaded, polarized or
special purpose lenses
as suitable.
See Note 3.
B, C, D, E, G,
H, I
Spectacle or goggle
specifically intended for
the laser being used.
Special purpose lenses
specifically intended for
the type and power level
of the laser.
Adapted with permission from Vallen Safety Supply 1992 catalog.
Devices that do not
provide protection
from optical radiation.
See Note 4.
TABLE 2. LENS SHADES FOR CUTTING AND WELDING
Operation
Shielded metal arc
Shielded metal arc
welding
Electrode size
(inches)
Arc Current
(amps)
Minimum shade
permitted
Suggested
shade
less than 3/32
less than 60
7
-
3/32, 1/8, 5/32
60-160
8
10
3/16, 7/32, 1/4
160-250
10
12
5/16, 3/8
Gas metal arc welding
and flux cored arc
welding
Gas tungsten arc
welding
Air carbon arc cutting
11
14
7
-
60-160
10
11
160-250
10
12
250-550
10
14
less than 50
8
10
50-150
8
12
150-500
10
14
light
less than 500
10
12
heavy
500-1000
11
14
less than 20
6
6 to 8
Plasma arc welding
light
Plasma arc cutting
250-550
less than 60
20-100
8
10
100-400
10
12
400-800
11
14
less than 300
8
9
medium
300-400
9
12
heavy
400-800
10
14
Carbon arc welding:
-
-
14
Torch brazing:
-
-
3 or 4
Torch soldering:
-
-
2
Plate thickness
Gas welding:
Oxygen cutting:
in.
mm
light
under 1/8
under 3.2
4 or 5
medium
1/8 to 1/2
3.2-12.7
5 or 6
heavy
over 1/2
over 12.7
6 or 8
light
under 1
under 25
3 or 4
medium
1 to 6
25-150
4 or 5
heavy
over 6
over 150
5 or 6
NOTES:
As a rule of thumb, start with a filter shade that is too dark to see the weld zone. Then go to a lighter shade which
gives sufficient view of the weld zone without going below the minimum shade indicated in the table.
In oxy-fuel gas welding or cutting where the torch produces a high yellow light it is desirable to use a filter that
absorbs the yellow or sodium line in the visible spectrum.
SOURCES: ANSI Standard Z49.1-1983 and proposed revisions to the OSHA Standard for Cutting, Welding and
Heating, 29 CFR 1926.351