As hot weather emerges from the mild temperatures of springtime, employees and equipment alike require careful consideration.
By Joan Shirikian-Hesselton
Plants, yards and project sites are once again feeling the effects of seasonal changes. Unfortunately, as with many things, weather conditions are well beyond your control. However, there are certain things you can do to limit any negative impact on people and product from the hot-weather extremes that seem to hit all regions of the United States and Canada during the summer months.
Occupational safety and health regulations in the United States and Canada do not set a single value for the maximum temperature to which employees can be exposed at work, nor do they mandate at which temperature work should stop. U.S. OSHA’s General Duty Clause, Section 5(a)(1), requires each employer to “furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm.”
Even though there are no specific work-related temperature regulations, working in hot environments cannot be taken lightly. Safety programs should not be built solely around standards. Safety standards are the bare minimum and employers should strive to provide safe work sites, which often means exceeding the bare minimum set by standards.
Workers and the heat
Workers who are exposed to extreme heat or who work in hot environments may be at risk of heat stress. Exposure to extreme heat while working can increase the occurrence of occupational illnesses or injuries. Individuals at greater risk of heat stress include those who are 65 years of age or older, overweight, have heart disease or high blood pressure, or take medications that may affect how they react to heat. However, heat stress can affect anyone. Other factors that can affect a person’s sensitivity to heat include degree of physical fitness, metabolism, use of drugs (prescription and nonprescription) and alcohol, and a variety of medical conditions. Heat stress can result in heat stroke, heat exhaustion, heat syncope (fainting), heat cramps or heat rashes. Heat may result in things like sweaty palms, fogged-up safety glasses or dizziness, all of which may increase the risk of accidents and injury in workers. Burns or other skin irritations may occur as a result of contact with hot surfaces, steam or overexposure to harmful radiation.
Prevention and adaptation
Prevention of work-related heat stress is important, and fortunately prevention is something that can be achieved. One critical element in preventing work-related heat stress is to ensure employees understand what heat stress is and how it can be prevented. Therefore the first step in preventing work-related heat stress is to ensure employees have received timely education on protecting themselves against heat stress, symptoms that indicate heat stress and what to do if they or their co-workers encounter heat stress-related issues. It is important that employers continue to provide frequent reminders throughout the season on all of these aspects regarding heat stress.
When the first wave of warm weather hits, your body hasn’t had time to become acclimatized to the heat, and so it can’t withstand what it handled last year or what it will be able to withstand later in the season. The same is true for new hires or for someone who has been away from work for a period of time. As noted in Canada’s National Occupational Health & Safety Resource materials, “The body adapts to a new thermal environment by a process called acclimatization. Complete heat acclimatization generally takes six to seven days, but some individuals may need longer. Loss of acclimatization occurs gradually when a person is moved permanently away from a hot environment. However, a decrease in heat tolerance
occurs even after a long weekend. As a result of reduced heat tolerance, it is often not advisable for anyone to work under very hot conditions on the first day of the week.” The U.S. OSHA provides detailed recommendations on its Web site and in its Technical Manual.
PPE in the heat
In addition, any personal protective equipment (PPE) that is worn may either appear to or actually add to the negative effects from the heat. Either way, heat or the discomfort from heat is never a reason to work without the proper PPE. Proper PPE can be selected to provide the required protection while also affording an adequate means for the body to release heat.
When working with cement and various additives, it is essential that certain precautions are taken to avoid skin exposure. Long-sleeved shirts and long pants are necessary to ensure minimal skin contact with substances that can cause irritation. It is not acceptable to swap out long sleeves for short sleeves because of heat or comfort issues. Skin needs to be protected from chemicals and the sun. Modifying PPE from the manufacturer’s original state is never acceptable. Punching holes in hard hats may seem to feel cooler, but if the hard hat didn’t come from the manufacturer with vents, it is never an acceptable solution to add any type of holes or make other structural modifications. There are other safe actions one may take to ensure heat stress is controlled. Some of these acceptable and safe actions include:
- Take rest breaks. Rest in a cool, shady spot. Use fans if appropriate.
- Drink plenty of appropriate fluids (cool drinking water).
- Do the heaviest work in the coolest time of day.
- Work in the shade whenever possible.
- For heavy work, rotate workers so that some can rest with lighter tasks or tasks in areas with less sun.
What you eat and drink also can affect how your body reacts to the heat. It is essential that you frequently drink water. You should never feel thirsty. If you become thirsty at any point, you are not drinking enough water. If you are drinking adequate water throughout the day, you will never feel thirsty. It is important to avoid drinks with caffeine, alcohol and large amounts of sugar. These beverages do not hydrate the body but actually rob the body’s cells of the water needed to keep them hydrated properly and increase the risk of heat stress.
Salt and fluid supplements
When working in a very hot environment, a person loses water and salt through sweat. This loss needs to be compensated by water and salt intake. Fluid intake needs to equal fluid loss to maintain the body’s equilibrium. It generally takes about one quart of water each hour to replace the fluid loss. Plenty of cool drinking water should be available on the job site and workers should be encouraged to drink water every 15 to 20 minutes even if they do not feel thirsty. As previously stated, alcoholic drinks should never be consumed in this environment, as alcohol robs the body’s cells of water.
An acclimatized worker loses relatively little salt through sweat and therefore the salt in a normal diet is usually sufficient to maintain the electrolyte balance in the body fluids. Unacclimatized workers tend to sweat more profusely and repeatedly and therefore lose more salt, so they may need to increase their salt intake by adding additional salt to their
normal diet. Salt tablets are not recommended, because they do not enter the system as quickly as water or other fluids. Too much salt can cause higher body temperatures and increased thirst and nausea. Workers on salt-restricted diets should be reminded to discuss with their doctor the type of work they perform and the possible need for supplementary salt.
Drinks specially designed to replace body fluids and electrolytes may be taken, but for most people they should be used in moderation. These drinks may be beneficial for workers who have physically active occupations. Since these drinks generally add unnecessary sugar or salt to the diet, they should not be used exclusively, and they should be supplemented with water. A recommended option is fruit juice or sport and electrolyte drinks diluted with water to half the strength. Drinks containing alcohol or caffeine should never be taken, as they dehydrate the body. For most people, water is the most efficient fluid for rehydration.
As both U.S. OSHA and the Canadian Centre for Occupational Health and Safety note in their publications, people are generally unable to notice their own heat stress-related symptoms. Their survival depends on their co-workers’ ability to recognize these symptoms and seek timely first aid and medical help. Employers should have emergency first aid procedures in place regarding heat stress and make certain employees are fully informed on these procedures.
Physical concerns with the change of season
After the winter season, the plant – including the yard, equipment and vehicles – needs special safety inspections. Whether the winter/spring season has brought rain or snow, many things need to be considered and inspected as spring/summer production begins.
All equipment and structural fixtures need to be inspected. This is especially important for anything that has not been used during the previous season. Rust may set in and weaken key components while weather may cause other forms of deterioration. Any electrical components that have been subjected to the elements should be properly inspected and tested.
Vehicles that have not been used need to be inspected prior to being put into service. This includes inspection of mechanical and safety features. All safety equipment should be inspected to ensure it is functioning and in full compliance with all expiration dates and other details. During the inspection, areas need to be inspected where birds, bats or other animals could have entered the property or buildings. Take special precautions when cleaning any remains, bedding, droppings or other animal debris. Bird and bat guano carry various disease-causing organisms. The main disease organisms found in bird droppings are cryptococcosis, histoplasmosis and psittacosis, all of which can be dangerous to humans. Prevention of these diseases relies on avoiding exposure to contaminated dust. Therefore it is essential that any accumulated bird droppings are left undisturbed until a safe cleanup and disposal can be undertaken. This generally involves soaking the material, full use of PPE including appropriate respiratory protection, and special disposal of the droppings to
avoid future contamination. Prior to any cleanup, employees need to be informed of all potential hazards including health hazards. The inspection should also look to identify any means to modify the area to prevent birds or bats from re-entering.
During the season it is especially important to be mindful of what is taking place in the yard. With changes in the weather it is not unusual to see a shift in the ground or other supports from heavy rains, freezing, thawing or heavy winds. Any areas where product is stacked or supported need to be inspected for structural stability prior to use and on a routine schedule
when being used. It is too easy to assume things are status quo when in fact stored product is actually unstable because the support system has shifted when the ground heaved from an unusual weather situation. This can be a critical safety hazard. Heavy equipment moving near this product could cause a major incident.
The preseason inspection should cover all areas normally covered during full inspections but needs to ensure a very critical eye is given to any area or equipment that has been stored or left unused during the previous season. Additionally, prior to being put into service the equipment and the operator(s) need to be reviewed to ensure all applicable certifications are
As the seasons change it is too easy to overlook the activities that are taking place off site. Repair and field activities require the same preparation that takes place at the plant. This includes inspections of equipment, vehicles and work sites, and training with certification reviews for all applicable employees. Depending on the location and condition of the job site, employees involved in these activities may also require information on Lyme disease. For more information about Lyme disease, visit www.osha.gov/OshDoc/data_LymeFacts/lymefac.pdf (case sensitive).
As the seasons change, you can make sure that employees and facilities are equipped to handle the weather-related challenges by taking these proactive steps. The safety of your employees may depend on it.
How to Prevent Heat Stress
Employers should take the following steps to protect workers
from heat stress:
- Schedule maintenance and repair jobs in hot areas for cooler months.
- Schedule hot jobs for the cooler part of the day. Consider earlier start times if lighting conditions permit a safe work environment since it is generally cooler in early morning hours.
- Acclimatize workers to the heat (set up a system that exposes them for progressively longer periods to hot work environments).
- Reduce the physical demands of the workers.
- Use relief workers (job rotation) or assign extra workers for physically demanding jobs.
- Provide cool water or liquids to workers.
- Avoid drinks with caffeine, alcohol or large amounts of sugar.
- Provide rest periods with water breaks.
- Provide cool areas for use during break periods.
- Monitor workers who are at risk of heat stress.
- Provide heat stress training that includes information about: Worker risk, prevention, symptoms, the importance of monitoring yourself and co-workers for symptoms, treatment, personal protective equipment
Joan Shirikian-Hesselton is an independent Occupational Safety and Health consultant. She has more than 30 years of experience in Occupational Safety and Health in both the public and private sectors, including a decade of dedicated experience in the precast/prestressed concrete industry. She is a past NPCA Safety, Health & Environmental Committee chair, and she has worked with U.S. OSHA as a Special Government Employee.