Hot tips on cooling the workplace

With extreme temperatures expected again this summer around Australia, manufacturers need to understand their legal obligations for safety of employees working in the heat. Alan Johnson reports.

Aside from specific or prescriptive requirements in some jurisdictions, all employers have a general duty to address problems with heat in the workplace. Industrial safety professionals say the primary means of achieving this duty of care is to undertake risk management.

As a general proposition, they suggest a risk management approach be adopted in consultation with employees, looking at what are the hazards associated with working in high temperatures and what control measures can be implemented to keep the risk as low as reasonably practicable.

The first step is to identify the sources of heat, by looking at the work environment, the plant used and work processes and practices.

The effects of heat on the body are influenced by environmental factors such as:

Air temperature – how hot the surrounding air is.

Humidity – the moisture content in the air.

Air Movement – including air speed and air circulation.

Radiant Heat – heat radiating from the sun, or emitted by plant, buildings, fixtures or processes.

Some possible effects from exposure to hot environments include fatigue, sweating, dizziness, nausea, vomiting, slurred speech, and collapse.

A risk assessment will help determine how serious a manufacturer’s heat related problems could be.

Some of the risk factors that will need to be considered include the source of the heat, the nature of the work undertaken, the duration of exposure to heat, the physical condition and capability of the worker and past experience of problems arising from work in hot environments.

Legislation

Under current legislative regimes there is no prescriptive ‘maximum temperature’ that employees may be exposed to. This is due to the vast array of working conditions across industries and work activities, with each Australian state having slightly different legislation.

In Victoria, for example, the state’s Occupational Health and Safety Act 2004 requires employers to provide and maintain, so far as is reasonably practicable, a working environment for employees that is safe and without risks to health and safety. Health in this context includes any illness from working in heat.

WorkSafe Victoria has published a Guidance Note Working in Heat which provides guidance on ‘thermal comfort’. It states that while thermal comfort is subjective, “…generally, conditions considered comfortable for people working indoors and doing light work are: air temperature (dry bulb temperature) 23 to 26degC and relative humidity 30 to 60%”.

In NSW the legislation which currently applies to the issue of temperature and heat in the workplace is the Occupational Health and Safety Act 2000, however there are no prescribed temperature maximums.

In Queensland, the state’s Workplace Health and Safety Act 1995 requires a risk management approach to managing thermal stress, with no prescribed temperature maximums.

In WA, the Western Australian Occupational Safety and Health Regulations 1996 requires an employer to ensure that work practices are arranged so that employees are protected from extreme heat. Cooling should be provided in a building or structure as far as practicable, to enable employees to work in a comfortable environment.

Prevention

While it is not always possible to eliminate heat from a workplace, the effects can be minimised by using a number of strategies, which might include providing a short break for a cool drink in the shade; scheduling outdoor work so that it is in the cooler part of the day; installing screening across windows which let in the direct sun; through to planting trees outside the building for a longer term effect.

Additional measures may include ensuring adequate drinking facilities, providing shade where possible, monitoring temperatures in the workplace, rotation of people or duties, scheduling heavy work and tasks that require the wearing of PPE for cooler times of the day, development of first aid and emergency procedures.

With air conditioning rarely an option for manufacturers, due to the operating costs and the design and operation of the buildings, many companies utilise large industrial fans to keep their workers cool in their warehouses and manufacturing facilities.

When temperature and humidity levels rise, the body’s natural ability to cool itself decreases.

However, Big Ass Fans marketing manager for Asia Pacific, Max Jamwal-Girdler explained that while air movement does not lower the actual temperature of a space, the airflow from a powerful fan can make people feel up to 12 deg C cooler. He offered five tips:

Cooling breezes – With some of the company’s models reaching 7.3m in diameter, high-volume, low-speed fans have the power to move air throughout the entire space, from ceiling to floor and wall to wall, including up and over obstructions such as machinery and stacked product to ensure climate conditions are consistent throughout.

Lower energy costs – Industrial fans aren’t just for non-air conditioned facilities. By using energy-efficient fans in conjunction with air conditioning, building managers can raise their air-conditioning setpoints to save up to 30% on cooling costs without compromising comfort.

The same is true in the wintertime. Companies can save up to 30% on heating costs by using fans.

Improved air quality – The airflow pattern of the company’s fans ensures air reaches all corners of an industrial space, maintaining consistent conditions throughout and eliminating stagnant areas where product integrity is a concern. It’s also more pleasant for employees.

Janwal-Girdler said US spirits and wine company Brown-Forman learnt that the hard way. After moving three bottling lines into a refurbished warehouse that lacked air conditioning, management recognised they had a problem. With a dated building structure and a total lack of air movement, stale air encompassed the facility, and the 50 employees working in the space were less than pleased.

Aware of the importance of employee comfort, Brown-Forman’s Reliability Manager, John Willis, organised the installation of six 7.3m) fans and one 6.1m fan above the bottling lines. Besides the cooling effect they have on employees, the fans sweep stagnant air away from occupants. This refreshing breeze also helps increase the perceived indoor air quality, leading to happier, more comfortable, workers.

Heat destratification – As well as for summer, the massive airfoils of Big Ass Fans are also adept at moving large volumes of heated air for better circulation and more even temperatures in the winter.

Air from heaters is approximately 5-7% lighter than cool air, so it tends to rise to the ceiling. In the winter, a slow-moving fan can efficiently mix huge amounts of air without generating a chilly draft. Recirculating heat trapped near the ceiling back down to occupants improves comfort and can greatly reduce heating costs.