Louisiana in the summertime is a hot, humid place. Sit still and you sweat. Move and you sweat. Work outside for an hour or two and you understand the phrase, "Hotter than H-E-double hockey stick."
Just ask the employees of Ford, Bacon & Davis LLC of Baton Rouge, who are suited up in hard hats, chemical goggles, fire-retardant clothing, gloves and steel-toed shoes or boots whenever they head out to the chemical processing facilities of the region's oil producers. (Note: Ford, Bacon & Davis LLC was named one of America's Safest Companies in 2004 by OCCUPATIONAL HAZARDS.)
"We are serious about heat stress education," says Keith Sliman, safety director for the company's 450 employees in three southern states. "Starting in June, I send out e-mails, put up posters and talk to employees about heat stress and working outside in heat and humidity."
Employees are given copies of heat index charts that map humidity and temperature. Sliman checks weather reports at the beginning of each week starting in June and notes the predicted heat indexes. If they are high, he notifies employees to be careful while working outside or tells them not to work outside at all. "They're told to plan their day with the heat index in mind. If it's too hot, then they need to plan to work inside," he says.
Part of his educational presentations about heat stress and working during the summer months includes precautions against rolling up sleeves and unzipping coveralls until the employees are in "safe" locations. When they are out in the pipe racks of a chemical processing facility, they'd better be covered up.
"We give them permission to stop work if they get too hot. I tell them, 'Go to a safe place. Unzip the coveralls and let the sweat evaporate. Cool down. Then go back to work,'" says Sliman.
All too often, in the summer months, you see workers who have compromised the integrity of their protective clothing by cutting off the sleeves or unzipping the garment, says Ralph Solarski, associate marketing director, Kimberly-Clark Safety Business. "That means they're either hot, or the garment doesn't fit properly."
Kimberly-Clark manufactures coveralls out of Kleenguard fabric, which allows air permeability while still offering particle protection. The garments are constructed to have more room to allow better airflow. Kim Dennis, a research scientist at Kimberly-Clark, points out that "if a coverall has been breached, because the employee cut slits in it or the seat blew out, then it is not offering any level of protection. They might as well not be wearing it."
Employers face a difficult task, she adds. "They have to assess what is the best coverall for their workers by balancing many factors, such as risk of exposure and comfort." Dennis offers this anecdote as a way of illustrating her point: A couple of years ago, she conducted an educational session about protective clothing at the American Industrial Hygiene Conference and Expo. She remembers an industrial hygienist coming up to her after the session and telling her, "We experience relatively small exposures with health risks that might or might not be long-term, but I know one thing for sure: Heat stroke and heat stress are immediate and can cause a life-or-death situation that day. Which exposure is more acute?"
"The hygienist had to balance health or comfort, and the long-term and short-term risks," Dennis points out. "What was the greater hazard the threat of heat stroke that day or an exposure that might cause illness years down the road?"
Comfort Versus Protection
Garment and cloth manufacturers understand the comfort issues facing workers who must wear protective clothing in hot months. They also are aware that comfort levels can vary from worker to worker.
"Comfort is a subjective and very complex perception," says Dawn Werry, global marketing communications manager, Industrial Segment, DuPont Safety and Protection, which manufactures a number of protective fabrics, including Tyvek and Nomex. "It is a combination of thermal, tactile and psychological perceptions by the wearer."
Psychological factors, says Werry, include appearance, style and color, as well as the needs of the individual worker (longer arms, shorter torso, etc.) Tactile factors include the feel of the fabric and the fit of the garment. The final factor is thermal: How hot is the garment?
According to Werry, "Tests reveal that fabric weight is a critical factor in determining on-the-job comfort, especially in hot and humid environments. In addition, breathable fabrics permit rapid movement of heat away from the body, helping to keep workers cooler."
Protecting workers against certain thermal hazard levels can limit the fabric and garment manufacturers' ability to make lightweight garments. For instance, for electric arc protection, heavier weight fabric structures often are required to get the appropriate level of arc protection.
"The challenge is to balance protection and comfort," acknowledges Mike Jeffrey, president of Protective Textile Solutions Inc., which is a sales agent for manufacturers of protective fabrics .
He says one thing manufacturers are doing a better job of is matching garments with the hazards of the job. For example, employees who do not have to worry about high-heat hazards probably don't need heavier-weight fabrics to be adequately protected, so manufacturers are developing lighter-weight protective fabrics.
"Six years ago, along the Gulf Coast, workers were wearing fabric weights of 9 ounces a square yard for treated fabrics and 7 ounces a square yard for Nomex. Now, you'll see a lot of those workers wearing 7-ounce treated fabric and 4.5-ounce Nomex. That's a shirt-weight fabric and it's more comfortable," says Jeffrey.
Hal Bates, marketing manager at Glen Raven Inc., compares the wearability of some of the new fabrics on the market to the difference between wearing business attire and having casual dress Fridays. "Before, some workers didn't have the opportunity to wear more comfortable protective clothing. All the clothing was hot and scratchy. Now, there are fabrics on the market, such as our GlenGuard, that have a yarn blend that offers protection but doesn't scratch."
Other manufacturers are coming up with unique solutions to the challenge of making protective clothing more comfortable. Take Canadian company Pro-Vents Appairel Ltd. Founded by a former steelworker who knew first-hand the challenges of wearing protective clothing in a hot environment, the company offers a line of protective pants with zippered vents that are covered in flame-resistant mesh.
Hydrate, Hydrate, Hydrate!
For workers at Ford, Bacon & Davis, however, some lighter-weight garments or innovations like zippered vents are not an option. A flash-fire or explosion at a chemical or petroleum facility is unforgiving. As is heat stroke.
"My mantra is, 'Hydrate, hydrate, hydrate,'" says Sliman. "I tell our employees to drink water before they go out to work. Drink water while they're working. Drink water when they come back inside, even if they don't feel thirsty. Mix some sports drinks in there to replace the electrolytes they're sweating out."
Sliman tells workers not to forget his mantra when they go home. "Heat stress doesn't stop at 4:45 p.m. when they get off work . They need to properly hydrate while they're mowing the lawn or playing ball. And proper hydration doesn't mean a Bud Light or iced tea with sugar. Those might taste good going down, but the alcohol and the caffeine dehydrate you. Hydration means water," Sliman notes.
He says employees will see him coming and before he can say anything, they shout, "Hydrate! Hydrate! Hydrate!"
"It's kind of encouraging," he admits. "I know they're listening to me."
Sidebar: How Employers Can Reduce Heat Stress for Workers
There are several steps employers can take to help reduce heat stress for their workers wearing protective apparel.
Encourage employees to wear protective apparel that is appropriate for the hazard.
Dawn Werry of DuPont suggests conducting a hazard assessment to select the proper level of protection for the hazards their workers may face. "To reduce heat stress, workers should wear protective apparel that is appropriate for their jobs, not apparel that protects well beyond their hazard level," says Werry.
Keith Sliman of Ford, Bacon & Davis LLP reminds his employees to stay hydrated and to drink water before they go out in the field, while they're out performing job tasks and when they come back inside. Employees are also empowered to stop work and take a break if weather conditions become too hot or humid.
Layer garments to balance comfort and protection needs for different tasks.
Werry points out that some employees may have some jobs that require a base level of protection for most of their job tasks, but need a higher level of protection for a few job functions or work areas. For those situations, employees could layer flame-resistant garments to meet a variety of protection needs. On a regular basis, workers should wear a protective garment that is as lightweight and breathable as possible, but still meet the protection needs of their job function, based on their hazard assessment.
"For job tasks that require higher levels of protection, workers should use a second flame-resistant garment layer, such as a coverall, over the first layer," she says. "When combined with the base garment, the second flame-resistant layer offers the flexibility to protect against higher thermal hazards and can be removed when not needed. This balances the everyday need for lightweight, breathable, comfortable garments with a short-term need for greater levels of protection."
Engineer out the hazard.
Personal protective equipment (PPE), such as flame-resistant protective apparel, is designed to be the last line of defense for employees. "By identifying the hazards that workers might face and then engineering out or reducing the hazard level, employers can often reduce the required flame-resistant protection level needed for protective garments," says Werry.
For instance, by adjusting the setting for circuit breakers, employers may be able to reduce the arc energy level to which a worker could be exposed, reducing the required electric arc protection level for their protective garments. They can also adjust work practices and train employees to reduce the likelihood of encountering a flash fire or electric arc hazard.