Health and Safety ReportVolume 12, Issue 5

If you work with or near hazardous chemicals, you should know the appropriate safety precautions to take to work safely and avoid injury. However, accidents can happen - and when a corrosive chemical gets into your eyes or on your face or body - the first few seconds are the most critical for preventing injury. If treatment is delayed, even for a few seconds, serious injury may be caused.

That's where emergency showers and eyewash stations come in, providing workers with on-the-spot decontamination and the ability to flush hazardous substances away, and minimize the effects of accidental exposure to chemicals.
There are different types of units available - emergency showers, eyewash stations and combination units. The type of protection selected should match the hazard, and the chemicals that are used at the workplace. Conducting a job hazard analysis will help you identify this information.

Emergency showers are designed to flush the user's head and body. These are NOT for flushing the eyes, because the water pressure may be too great and could damage the eyes.

Eyewash stations are designed to flush the eye and face area only.

Combination units contain both an emergency shower and an eyewash station and enable any part or all of the body to be flushed. They are the most protective emergency devices and should be used wherever possible.

Flushing time*

The American National Standards Institute (ANSI) Standard for Emergency Eyewash and Shower Equipment (ANSI Z358.1-2009) recommends that the affected body part must be flushed immediately and thoroughly for at least 15 minutes using a large supply of clean fluid under low pressure. Water does not neutralize contaminants -- it only dilutes and washes them away. This fact is why large amounts of water are needed.

Other references recommend a minimum 20-minute flushing period if the nature of the contaminant is not known, however, the time can be modified if the identity and properties of the chemical are known. For example:

• minimum 5-minute flushing time is recommended for mildly irritating chemicals,


• at least 20 minutes for moderate-to-severe irritants,


• at least 20 minutes for non-penetrating corrosives, and


• at least 60 minutes for penetrating corrosives.

Remember to always keep a clear, unobstructed path to the emergency shower or eyewash station at all times, and to frequently test the unit to ensure it is well maintained and operating correctly.

Water temperature*


The 2009 ANSI standard recommends that the water should be "tepid", between 16-38°C (60-100°F). Temperatures higher than 38°C (100°F) are harmful to the eyes and can enhance chemical interaction with the skin and eyes. Long flushing times with cold water (less than 16°C (60°F)) can cause hypothermia and may result in not rinsing or showering for the full recommended time (ANSI 2009). With thermal burns (injuries to the skin), the American Heart Association noted that optimal healing and lowest mortality rates are with water temperatures of 20-25°C (68-77°F).

Remember that any chemical splash should be rinsed for a minimum of 15 minutes but rinsing time can be up to 60 minutes. The temperature of the water should be one that can be tolerated for the required length of time. Water that is too cold or too hot will discourage workers from rinsing or showering as long as they should.

Install anti-scalding devices (temperature control valve or thermostatic tempering valve), constant flow meters, and other devices that will help maintain a constant temperature and flow rate. For cold or outdoor locations, emergency showers with heated plumbing are available. In hot climates, outdoor emergency showers should also have a tempering valve so that workers are not exposed to water that is too hot.

Training

Employers should inform their workers where the emergency showers or eyewash stations are and instruct them on the proper way to use them. Worker should also have access to written instructions and they should also be posted beside the emergency shower and eyewash station. Part of the training should include a "hands-on" drill on how to find equipment.

Wearing contact lenses can be dangerous, and training should include instruction in contact lens removal. Chemicals can become trapped under a contact lens and any delays caused by removing contact lenses in order to rinse eyes could cause injury.

Location of the emergency equipment

To be effective, the equipment has to be accessible. ANSI recommends that a person be able to reach the equipment in no more than 10 seconds. ANSI notes that the average person can walk 16 to 17 metres (55 feet) in 10 seconds, but this does not account for the physical and emotional state of the person.

However, the "10 second" rule may be modified depending on the potential effect of the chemical. Where a highly corrosive chemical is used, an emergency shower and eyewash station may be required within 3 to 6 metres (10 to 20 feet) from the hazard. These units should be installed in such a way that they do not become contaminated from corrosive chemicals used nearby.

The location of each emergency shower or eyewash station should be identified with a highly visible sign in the form of a symbol that does not require workers to have language skills to understand it. The location should be well lit.
The emergency shower or eyewash station should be located:

• as close to the hazard as possible


• on an unobstructed path between the workstation and the hazard. (Workers should not have to pass through doorways or weave through machinery or other obstacles to reach them)


• where workers can easily see them - preferably in a normal traffic pattern


• on the same floor as the hazard (no stairs to travel between the workstation and the emergency equipment)


• near an emergency exit where possible so that any responding emergency response personnel can reach the victim easily


• in an area where further contamination will not occur


• in an area protected from freezing when installing emergency equipment outdoors


• away from any electrical equipment that may become a hazard when wet

There must also be a drainage system for the excess water (the water may be considered a hazardous waste and special regulations may apply).

Consult your local occupational health and safety agency in your jurisdiction and check relevant legislation for any requirements to install this equipment. Currently there is no Canadian standard for the design or placement of eyewash stations or emergency showers. As a result, the American National Standards Institute (ANSI) Standard for Emergency Eyewash and Shower Equipment (ANSI Z358.1-2009) is generally used as a guide.

Read more in CCOHS' OSH Answers.

*Article updated June 6, 2014, after original June 3, 2014 publication.

Fresh back from presenting at the Singapore Workplace Safety and Health Conference 2014, Steve Horvath, President and CEO of the Canadian Centre for Occupational Health and Safety shared his reflections in a recent blog post on the event and the theme, "Integrating Safety and Health: Towards A Holistic Approach".

I applaud the commitment by the most senior government officials in Singapore for showing leadership and enabling a whole nation to achieve a common goal of eliminating injury and illness in the workplace through political engagement. It not only provides a lot of momentum, but also confidence to health and safety practitioners when progressive policies are promoted by all levels of government and supported by labour and industry.

Government, labour and employers were present at the Singapore Workplace Safety and Health Conference 2014 to promote and understand the challenges and were committed to make this happen.
I am impressed by the broad level of commitment demonstrated by world-class health and safety organizations like the Workplace Health and Safety Institute (WHSI) and the Workplace Safety and Health Council. Their support comes from clear and consistent leadership from the highest levels of the national government. During various times of the ASEAN-OSHNET meetings and the conference, the Deputy Prime Minister and Minister of Finance, Senior Minister of State and Minister of Health and Manpower, and the Senior Parliamentary Secretary and Minister of Education and Manpower delivered addresses, while other senior Ministry officials were also in attendance. It is refreshing to see all of them speak of a singular vision for a Singapore without workplace injuries and illnesses and their support for the country's "Vision Zero" action plan for achieving their goals.

In his opening remarks, the Deputy Prime Minister and Minister of Finance for Singapore, Tharman Shanmugaratnam, acknowledged the challenge ahead but reaffirmed the government's resolve in achieving the OSH goals of the nation. He spoke of the need to integrate worker health issues with workplace safety, and for industry to take a holistic approach to OSH if they were going to eliminate injuries and illnesses in Singaporean workplaces - a problem that is costing the country 3.2% of their GDP. Consequently, OSH prevention strategies are recognized as part of the overall growth strategy for the region. A trade deal to be completed within the year with all the other ASEAN countries will include common standards on health and safety that are based on global best practices.

Other Ministers reiterated the key concept of adopting a holistic approach to protecting the safety, health and well-being of employees. Hawazi Daipi, the Senior Parliamentary Secretary for Manpower and Education noted that with Singapore's aging population and increasing life expectancy, all organizations have to put in place holistic intervention programs to ensure health and safety and a sustainable workforce.

With CCOHS recognized as a global leader whose expertise, infrastructure and capacities are viewed as true strengths, I was there to present evidence and data supporting the integration of health and safety with the business processes of an organization. It is always encouraging to see the enthusiasm that other countries show in learning about CCOHS' experiences and approach to prevention programs. It is a competitiveness issue for organizations. For a robust management system to exist, you have to consider OSH as part of the normal decision-making process with all employees. If it is seen as a separate program, it will not result in a cultural shift in the workplace because it will not become part of the normal decision-making process of the organization and will be perceived by management as part of the problem instead of part of the solution. What is necessary is worker engagement through leading by example, communication, coaching and management commitment.

Read Steve's blog, Workplace Health and Safety Matters.

Saw mills are just one of the many workplaces that generate large amounts of wood dust. Others include construction sites, wood floor refinishing and installation, pulp and paper manufacturers, carpentry shops and logging sites.

Wood dust is combustible, and must be safely removed before it builds up and causes a fire or combustible dust explosion. Using vacuum trucks can be a safe and effective method of removing wood dust from buildings, machinery, and equipment.

Static electricity is one of the hazards that employers and vacuum truck operators need to be aware of when vacuuming wood dust. Static electricity discharges can ignite wood dust, and therefore must be eliminated or adequately controlled during vacuuming.

WorkSafeBC issued a bulletin with some important steps that vacuum truck operators can take to minimize the hazards of static electricity discharges when they are removing wood dust, as well as advice on the right equipment and safe work procedures to use. Employers who hire vacuum truck operators to remove wood dust from their premises should also be aware of this information.

Choose suitable hoses, nozzles, and connectors

When vacuuming wood dust or other dry combustible materials, use only conductive hoses, nozzles, and connectors that are designed to be used with those types of materials.

When wood dust is vacuumed through a hose (or pipe) the friction between the dust and the hose can generate static electricity. Hoses made of material that conducts electricity and which are properly grounded are safe to use. However, hoses that are made of plastic or other materials that don't conduct electricity are unsafe to use unless they are embedded with a grounding wire to prevent static build-up.

Also, hoses with ridged or corrugated surfaces inside the hose should not be used for vacuuming wood dust. The ridged interior surfaces cause more physical interaction between the dust particles, and between the dust particles and the hose, and increase the risk of igniting the dust.

Ensure proper grounding and bonding

Before vacuuming starts, trucks should be grounded directly to the earth or another verified ground, and the hoses and all other parts of the truck and vacuum system should be properly bonded to each other. Take extra care that the bond between the truck's air pollution control device (baghouses) and its filter cages is adequate because the large volumes of dust and air that flow through them increase the risk of ignition.

Inspect and maintain equipment

Regularly inspect and properly maintain vacuum trucks, giving extra attention to hoses, baghouses, vacuum pumps, collection boxes, and filtration systems. Test the conductive hoses regularly and stop using them if they have lost their conductivity.

Follow safety requirements to protect workers

Vacuum truck operators and employers who hire vacuum truck operators to remove wood dust should take these safety precautions:

• Remove wood dust before build-up of the dust can cause a fire or combustible dust explosion.


• Eliminate or adequately control static electricity and all other sources of ignition while combustible dust is vacuumed.


• Ensure that each tool, machine, and piece of equipment in your workplace is capable of safely performing the functions it is used for.


• Ensure workers follow manufacturer's instructions, safe work procedures, and meet the requirements of the occupational health and safety regulations in their jurisdiction.


• Inform workers of the known and foreseeable health and safety hazards they are exposed to through their work.


• Provide workers with the instruction, training, and supervision needed to ensure the safety of all workers at their workplace.

Read the full alert from WorkSafeBC.

More about combustible dust in CCOHS fact sheets.

Download the poster on combustible dust from OSHA.

This month's Health and Safety To Go! podcasts discuss ATVs in the workplace with tips on how to prevent injuries and feature an encore of summer sun safety with the Canadian Cancer Society.

Featured Podcast: Tips for a Safe Ride: ATVs and Work

With oversized, deep tread, low-pressure tires, relatively light weight, and easy manoeuvrability, all-terrain vehicles (ATVs) can go where other heavier, larger vehicles cannot. In this podcast, CCOHS explores using ATVs in the workplace and shares tips on how to prevent injuries.

The podcast runs 4:33 minutes. Listen to the podcast now.

Encore Podcast: Summer Sun Safety

Will you be working or playing outdoors this summer? Gillian Bromfield of the Canadian Cancer Society sheds some light on summer sun safety.

The podcast runs 3:44 Listen to the podcast now.

CCOHS produces free monthly podcasts on a wide variety of topics designed to keep you current with information, tips, and insights into the health, safety, and well-being of working Canadians. You can download the audio segment to your computer or MP3 player and listen to it at your own convenience... or on the go!

See the complete list of podcast topics. Better yet, subscribe to the series on iTunes and don't miss a single episode.