Q: What causes the hat to glow?
A: The glow is caused by photoluminescence, commonly referred to as Glow-in-the-Dark. The materials used in these hats are nothing at all like the glow-in-the-dark materials of several years ago. They charge quickly and glow much brighter and much longer than the glow-in-the-dark items you may remember having as a child.
Q: How long does it take to charge the hat?
A: Charging for 10 or 20 minutes in sunlight would be excellent to produce a stong lasting glow. A half hour in bright fluorescent light would be very good. Even 20 minutes near a 40W incandescent bulb will generate significant glow.
Q: How brightly does the hat glow?
A: In intermediate levels of lighting, the Glo-Mega takes on a greenish color as the glow competes with the light from its surroundings. In dark conditions, the Glo-Mega's glow has been measured at 1220 mcd/m2 immediately after charging and, after ten minutes, was still 45 times as bright as required by ASTM 2073 for emergency signage.
Q: How long can the glow be seen?
A: To eyes accustomed to the dark, the glow can be seen for several days or even weeks after a suitable change. The following table shows the brightness measured in one test at various intervals after a charge:
|Time in Dark
The average human eye can see a glow down to about 0.0032 mcd/m2.
(Some standards measure afterglow time as the time to fade 100 times that level or 0.30 mcd/m2.)
Q: How does the after-glow of the hat fade?
A: The fading begins as soon as the source of charging is removed - faster at first then slowing over a long period of time. For a number of hours, this fading is partially offset by a dramatic increase in the sensitivity of the eye to see light.
Q: What is the useful life of the product?
A: The hat has a normal life span of a molded polyethylene safety helmet. The photoluminescent properties, however, should last almost indefinitely.
Q: What is the difference between fluorescence and photoluminescence?
A: Both absorb light, especially ultraviolet, and then emit light at a different (usually longer) wavelength. Fluorescence is immediate and only visible during external illumination. Photoluminesscence is similar but the light emitted from the material is delayed so it is still visible after the illumination is removed.
Q: What are the blemishes that sometimes occur on the helmets?
A: Helmets are produced without the coloring pigments typically used in safety helmets. These pigments hide many minor blemishes but would drastically reduce the Glo-Mega's photoluminescent properties. The blemishes are naturally produced by the manufacturing process and are purely cosmetic in nature. They do not in any way reduce the effectiveness of the hardhat.
Q: Does the Glo-Mega meet OSHA requirements?
A: The hats fully complies with the ANSI Z89.1-2014 Standard for a Type 1 (crown impact), Class E, G and C safety helmet.
Q: Can the hat be imprinted or otherwise customized?
A: The hardhat can be imprinted. In this case, the logo or image will bee seen as dark against the glowing helmet. Also, flourescent and/or retroreflective adhesive strips can be added for daytime or illuminated nighttime conspicuity. Other decorations and attachments may be added provided that any adhesives that are used are compatible with the high density polyethylene shell.