Page 18 - Occupational Health & Safety, March 2018

SUMMER HAZARDS/HEAT STRESS
the most serious heat stress disorder. It oc- curs when the body’s systems of tempera- ture regulation fail and body temperatures rise to potentially fatal levels. It can be marked by an absence of sweating, as well as confusion, fainting, and/or convulsions. Hospitalization is a must for anyone who suffers a heat stroke.
Challenges in Heat Stress Control
Warehouses and loading docks are inher- ently fast-paced and dangerous environ- ments. Unfortunately, most loading docks are not air-conditioned and most dock staging areas have tall ceilings, making them hard to cool even if they are air-con- ditioned. The frequent opening and closing of doors is another added challenge to heat moderation.
Long-term weather patterns and the growth of online retailing are two other fac- tors that exacerbate this problem. Most U.S. states have seen their annual average sum- mer temperatures rise in the last decade, and scientists expect the uptick to continue. The ongoing expansion of online retailing and overnight shipping is another relevant trend because it forces e-commerce compa- nies to push fulfillment employees to work faster than ever.
Higher Temperatures =
More Mistakes, Legal Exposure
An uncomfortably hot facility not only lowers employee morale, it makes employ- ees less efficient. As more blood pumps to the skin in an attempt to cool off the body, less blood is available for vital organs such as the brain, leading to mental errors. In fact, a study done by NASA concluded that when in-plant temperatures rise to 85 de- grees F, worker output drops by 18 percent and errors increase by 40 percent.
While OSHA does not have specific regulations for indoor workplace tem- peratures, the agency recommends a tem- perature range between 68 and 76 degrees. Twenty-eight states have adopted OSHA- approved plans for compliance with and enforcement of heat illness prevention plans. Failure to comply with these regula- tions can result in a lawsuit if workers be- come injured as a result of heat illness.
Addressing Heat Stroke
There are a number of ways that facilities can address heat stroke issues. From a phys-
ical standpoint, water breaks should be en- couraged and workers who haven’t worked in these types of environments should be given time to acclimate. Obviously, anyone who displays heat stress symptoms should be moved to a cooler area, and anyone suf- fering a heat stroke immediately taken to the nearest hospital.
From an infrastructure standpoint, there are a number of facility upgrades that can have an immediate impact, such as up- grading dock seals and shelters at the load- ing dock to create a complete seal around the dock opening and using HVLS fans to circulate air.
Heating Up and Losing Energy
(and Money) at the Loading Dock The loading dock presents the greatest op- portunity for the loss of temperature con- trol and energy. Any opening can allow conditioned air to leave and outdoor hu- midity and foreign contaminants to enter.
Even when trailers are at the load- ing dock, gaps often exist between the trailer and the edges of the dock opening. Swing-open trailer doors usually lead to 1- to 2-inch gaps. While that might seem insignificant at first glance, it equates to a 2.5-square-foot hole at just one dock open- ing. That’s a lot of cool air escaping and/or hot air infiltrating a facility. Not to men- tion, depending on the climate of the fa- cility, this represents anywhere from $600 to $1,200 quite literally flying out the door every year. Now, extrapolate those figures over multiple dock doors, and the financial loss is significantly more profound.
But the sides of the dock opening aren’t the only gaps in the building’s perimeter. Many facility managers forget about the “fourth side” of the dock—the bottom end, where the leveler, trailer, and dock seal or shelter all meet. Depending on the size of the opening, that gap could result in more lost conditioned air and another $200 to $900 lost annually.
In almost all cases, the first rule of thumb is to look for light along the dock door perimeter—where there’s light com- ing through, there’s energy leaving the facility. If there’s visible daylight at your loading dock doors (typically on sides and tops of trailers), that means there’s a gap to be filled, and the right products need to be sourced for each type of gap.
Getting a consistent, gap-free seal along
trailer sides, tops, and corners, as well as at the bottom of dock door openings, is essen- tial to creating an environmentally secure and energy-efficient dock. An effective sys- tem of sealing products starts with a dock shelter that is specifically designed to over- come the most difficult sealing challenges.
Dock shelter head curtains help seal gaps and create a seal at the top of the trailer. However, sealing and blocking out daylight completely can be a challenge made worse at facilities that are serviced by trailers of varying sizes, where head cur- tains aren’t frequently adjusted correctly to reach lower trailers. Therefore, a head cur- tain that utilizes weight and gravity to cre- ate a solid connection with the trailer top is best, as the weight is necessary to maintain a tight, consistent seal across the full width of the trailer as it bounces during loading and unloading. Also, the head seal must au- tomatically adjust to a wide range of trailer heights without requiring pull ropes or other forms of manual adjustment.
On the sides of the trailer, keep the 2.5 cumulative square feet of opening created by exposed hinge gaps covered completely by hooks on the shelter side curtains. Facil- ity managers should also make sure dock shelters provide a solid seal at trailer top corners, where the side curtains and head curtain come together. This area is notori- ously difficult to seal and requires specially designed equipment to ensure an effective seal in this area.
While it is critical to effectively seals gaps at the top and along the sides of the dock opening, don’t forget the bottom. Gaps typically exist below and around the leveler and dock bumpers, which present another challenge for energy costs and in- dustrial hygiene. Installing a seal under the leveler can offer a barrier against the ele- ments on the facility’s exterior. Inside the dock area, lip corner seals, filler pads, and other components help retain conditioned air inside and warm air from entering.
Inside, HVLS Fans Help
Control Heat
While adding air conditioning is the best- case scenario, it isn’t always practical due to cost considerations and building configu- rations. With or without air conditioning, though, most heat stress-prone facilities will benefit immensely from HVLS fans.
Although smaller, floor-mounted fans
16 Occupational Health & Safety | MARCH 2018
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