Health & Safety

Safety

The health and safety of employees is the #1 priority of a business.  To meet this objective, the risks to
health and safety need to be identified and eliminated.

These risks include carpel tunnel syndrome, equipment, air quality and even the floor you
stand on.

Manual printing can create carpal tunnel syndrome – a painful injury to wrists,
elbows and shoulders.  The more force, for example, that a person applies
to a squeegee, the more that person is at risk of being injured.  This
risk can be reduced by using tight screens, sharpening the squeegees, and modifying
inks to print easier.

When mesh is not tight, it will deflect excessively and be a barrier against which the
squeegee is being drawn.  A soft mesh can even form a wave or ripple of
mesh in front of the squeegee.  Unfortunately, all mesh relaxes from
its own tension and from repetitive deflection during printing.  The higher
mesh counts like 120 deflect more and faster than more coarse mesh like 43
mesh.

A 120 mesh will relax 25% within two hours of being stretched close to its ultimate strength.  The
risks to physical well being can be reduced or avoided by using retensionable
screens.  Those screens at the high mesh counts should be retensioned
four times before being used the first time, and after each use.  After
several retensionings and 500 prints, the mesh will retain its tension.

Ink, particularly plastisol ink, can be stiff or loose when it comes out of the ink manufacturer’s
container.  Stiff ink offers more resistance to pulling a squeegee.  Therefore,
ink should be modified to make it easy to pull and deflect through a screen.  If
that ink is plastisol, the addition of ink without pigment, also known as soft
hand clear or base, will make printing easier on light colored garments.  The
pigment in the ink should not be thinned when printing on dark garments.  Plastisol
inks to be printed on light or dark garments can be made easier to print by
adding curable reducer.

A squeegee is a tool like a knife to cut ink.  If the knife is dull, it will not
cut easily.  Squeegees should be sharpened daily to make printing easier
and to reduce the risk of carpel tunnel syndrome.

The off-contact distance of mesh from the garment affects the resistance to pulling a squeegee.  The
least amount of off-contact distance, such as 1-2 mm when printing shirts,
presents less risk to the person printing than greater off-contact.

When tight screens are used with the mesh slightly off-contact, sharp squeegee and ink
that are easy to print, ink will be left on the top of the garment surface
rather than driven into the garment.  Printers interested in safety should
also notice that squeegee blades do not bend during printing.

Another equipment risk besides the screen and squeegee are the springs used to raise
screens.  If the springs have been heat tempered to increase the ability
to raise heavier screens, they will likely break suddenly like a gun being
fired.  Such springs should be covered or wired together to prevent pieces
of metal being projected across the room.  Similarly, barriers should
be placed around automatic machines to prevent people from walking into moving
presses.

The height of the printing surface also affects safety.  The person printing should
not extend his or her arms more than 45 degrees.  A greater angle will
put undue pressure on joints and possibly cause carpel tunnel syndrome. 

Shop lint and spray adhesives can get trapped in lungs and sinuses causing headaches
and reduced breathing capacity.  Long term exposure can strain a person’s
heart and cause a heart attack.  Conveyors should be vented outside the
work area with sufficient convection to draw all hint out.  Spray adhesive
can be replaced with paper that has adhesive or both sides.

Constant standing on hard floors can be hard on a person’s legs and back.  Besides
fatigue, damage to leg veins can be the result.  Rubber mats, or even
heavy cardboard, can be placed on the floor to protect people who stand a lot
during the day.

These are challenges to employee safety, but these risks are easily avoided without spending
any much money.