Tech Talk

Safety First

The wrong fixtures in harsh environments can even become fire and electric shock hazards if the fixtures aren’t certified for wet environments. Be sure to select luminaires that are certified by a nationally recognized testing laboratory (NRTL, i.e. UL, CSA, ETL, TÜV-SÜD) for wet environments. This is even more important than durability. Safety first.

An Ounce of Prevention

In harsh chemical environments, the best deal isn’t the lowest price fixture. The best deal is the reasonably priced fixture that will survive and perform well, with little to no maintenance. Lowest total cost of ownership, in these settings, means avoiding the hassle and considerable expense of replacing fixtures due to premature failure. There are many ways that fixtures can fail, if they’re not properly designed for chemical resistance. To protect your money and luminaire investment, do your research and only select chemical resistant luminaires that will survive your demanding application.

Low to no maintenance requirements are equally important in keeping down the total cost of ownership. Avoid luminaires utilizing legacy bulb technologies. Replacing bulbs is inconvenient, costly, and worst of all might shut down critical operations in your facility. Look for integrated LED technology with a long-rated lifetime. High IP rated fixtures that keep out dust and water will also eliminate the cost and disruption of having to clean inside a lens. High IP rated fixtures will also permit fast and easy spray cleaning, should the outside of the fixtures get dirty. A high IK impact rating will also reduce the risk of breakage from impacts, preventing costly maintenance or early replacement.

An Impenetrable Envelope

Many traditional style vapor tights are designed using gaskets and clips to seal the fixture, requiring assembly and often leaving multiple fail points that render it susceptible to intrusion. When searching for an impervious solution that can withstand prolonged exposure to harsh environments, it is important to consider the construction of the housing to mitigate risks in the long term. For linear fixtures, this means looking for continuous extrusions, without seams. Even better is co-extruded polymer and aluminum. The right polymer as the outside extrusion provides the chemical resistance, while the inner aluminum extrusion provides mechanical strength and thermal management for the LED and power components. The potential weak link in an extruded housing is at the end caps. Seek permanently welded end caps, to insure impenetrable bonding of the housing and end cap materials.

Although widely used, both polycarbonate (PC) and acrylic (PMMA) are known to succumb to harsh chemical environments. Chemical exposure can create small cracks in polycarbonate and acrylic that grow larger over time. Stresses within the material or impacts from outside eventually compromise the ability of these materials to keep out dust and liquids, creating potential fixture failures or even safety issues. Another problem with polycarbonate and acrylic diffusers is clouding of the diffuser, reducing light output from the fixtures. A modern alternative to these legacy polymers, copolyester (PETA) is a very durable polymer, commonly found in Nalgene bottles, and commercial bar-ware, is designed to withstand frequent commercial washing and rough handling. Seek luminaires with housing and lenses that avoid polycarbonate and acrylic resins, and look instead for copolyester polymer that can withstand harsh chemical exposures.