Health and Safety ReportVolume 10, Issue 1

On Topic

Work Leaving You Breathless?print this article

Work-related asthma and how to prevent it

He never smoked, was in good physical shape, and had been healthy for most of his life. So when the coughing and wheezing began, and then worsened, Michel knew something was very wrong. His doctor questioned him about the years he had spent at a workplace without proper ventilation - breathing in harmful chemicals. After further investigation, many tests and examinations, Michel's doctor diagnosed him with occupational asthma.

Asthma is a common lung disease that creates narrowing of the air passages making it difficult to breathe. It can affect your overall quality of life and your ability to work, and when asthma is not managed, it can even threaten your life. If you are exposed to certain workplace chemicals or agents, you may be at risk for developing occupational asthma.

Often people with work-related asthma do not realize that their symptoms are related to their work because they are the same as those for regular asthma: attacks of difficult breathing, tightness of the chest, coughing, and wheezing. However, in work-related asthma, the symptoms are usually worse on working days, and improve when the person is away from the workplace - on the weekend, days off and during vacations.

There are 2 types of work-related asthma:

  1. occupational asthma or respiratory sensitization, which is caused by exposure to an agent in the workplace

  2. work-aggravated asthma where factors at work worsen the condition of someone who already has asthma

Agents that can cause occupational asthma

There are many agents used in workplaces that can cause asthma in people working with them. Examples include certain:

  • chemicals including isocyanates

  • metals and metal-working fluids

  • dyes, drugs, and enzymes

  • grains, flours, plants, and gums

  • animal and shellfish proteins

  • fungi

  • wood dusts including red cedar

Factors that can trigger work-aggravated asthma

Workplace respiratory irritants and certain workplace factors can trigger work-aggravated asthma. These could include:

  • vapours, gases, dusts, mists, sprays or fumes from industrial materials and cleaning products

  • dust mites or mould/fungal spores

  • indoor air pollution resulting from poor ventilation

  • outdoor air pollution and smog (for outdoor workers)


Work-related asthma can be prevented by eliminating or reducing exposure to any agents that are known to cause it. Both employers and employees can help to prevent it.


  • Eliminate the asthma-causing/aggravating agent from the workplace.

  • Substitute a less hazardous agent if elimination is not possible.

  • Apply administrative controls such as policies, procedures, safe work practices, and job rotation to minimize exposure time of workers.

  • Control the exposure. Close off the work processes that release the agent into the air, or install ventilation systems to contain emissions, such as gases or vapours, at the source.

  • Provide personal protective equipment (PPE) such as respirators as the last line of defence. PPE should not be used as the only method of exposure control when exposures are ongoing.

  • Train employees on the proper use, storage and maintenance of PPE, proper handling procedures, avoidance of spills, and safe working and good housekeeping procedures.

  • Monitor the exposure level of hazardous agents in the workplace to make sure that workers are not exposed to levels greater than recommended in regulations, standards, and guidelines.


  • Learn about the hazards in your workplace by speaking to your employer, health and safety or union representative, or an occupational health professional.

  • Attend training courses on work-related asthma and occupational health and safety.

  • Be aware of the symptoms of work-related asthma.

  • Follow safe work practices, policies, and procedures provided by your employer.

  • Use the PPE provided.

  • Report any problems with equipment, PPE, or ventilation systems to your supervisor.

  • Participate in all health and safety programs in the workplace.

If you experience asthma-like symptoms, go to your doctor. If your doctor, or other health care professional, suspects that you may have work-related asthma, tell your supervisor, union representative, and joint health and safety committee immediately.

Work-related asthma is a serious illness that, if not recognized and treated early enough, and exposure is not reduced, can result in disability and job loss. It is important for employers and employees to work together to prevent work-related asthma so all may breathe easy at work.

For more information, visit The Asthma Society of Canada, or call the Allergy and Asthma Education Support Program 1-866-787-4050

Register for the FREE webinars Work-Related Asthma: Breathe Easier from Ontario Lung Association in cooperation with CCOHS.

Download the free Work-Related Asthma in Higher Risk Industries Booklet from Occupational Health Clinics for Ontario Workers Inc (OHCOW) PDF

Read the OSH Answers Fact Sheet on Occupational Asthma from CCOHS for a detailed chart of causal agents and related occupations at risk.

Tips and Tools

Safety Checklists Molded to Plastics Processingprint this article

Burns from hot plastic; injuries from expelled fragments; harmful effects from inhaled vapours or fumes; electric shock; crushed or amputated limbs; and even death - these are some of the hazards faced when working with horizontal plastic injection molding machines.

To help prevent injuries and illness in the plastics processing industry, the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST) collaborated with professionals from the plastics processing industry to produce a simple tool for checking safeguards for horizontal plastic injection molding.

Thermoplastic injection molding machines produce molded plastic parts by melting plastic pellets, injecting the molten material into a mold, and cooling the plastic material. This process involves many machine parts and tasks such as opening the operator's gate, servicing and maintaining the machinery (lockout/tagout), and manually feeding the plastics materials. Any one of these processes can cause a worker harm if the proper precautions are not taken.

The IRSST's Horizontal Plastic Injection Molding Machine - Safety Checklists is a collection of practical safety checklists for individuals who perform various tasks on these machines, such as production, tuning, or maintenance. The following checklists are available:

  • Safeguard checklist

  • Additional safeguarding for large molding machines

  • Safeguarding of the injection unit

  • Safeguarding of the mold closing unit

  • Safeguarding checklist for people working on the machine

These checklists refer to sections of the ANSI Standard for Plastics Machinery - Horizontal Injection Molding Machines - Safety Requirements for Manufacture, Care, and Use (ANSI/SPI B151.1 - 2007).

The IRSST document:

  • includes illustrations of the processes and machines used,

  • reviews the components of a horizontal plastic injection molding machine and the associated hazard zones, and

  • presents the safeguard checklists.

It can be used in basic training offered to employees and students in plastics processing. However, it doesn't allow a risk analysis to be done.

To prevent the serious, and even fatal, injuries associated with working horizontal plastic injection molding, employers must establish safety procedures, provide consistent training, and ensure safety measures are followed.

Download the Horizontal Plastic Injection Molding Machine Safety Checklist document from IRSST. [PDF]

Take the interactive Horizontal Injection Molding Machine Safety Tour from OSHA.

Partner News

Breathe Easier at Workprint this article

Free webinars demystify work-related asthma

Asthma is a serious illness, affecting about three million people in Canada. It can affect your overall quality of life and if not managed, can be life-threatening, cause permanent disability, and even lead to death. Work-related asthma - asthma caused by exposure to an agent in the workplace - is the most common occupational respiratory disorder in industrialized countries. It can greatly affect an individual's ability to work. Early, accurate diagnosis and treatment, plus changes in the workplace, can make a difference to the well-being of patients and their co-workers.


To help reduce the high financial and human health costs of work-related asthma, the Ontario Lung Association in collaboration with Ontario Thoracic Society Provider Education Program, McMaster University, the Occupational Health Clinics for Ontario Workers, and Health & Safety Ontario are providing workers, employers and primary care healthcare providers with up-to-date guideline-based education on work-related asthma through a two-part webinar series.

The webinars will be presented by Dr. Michael Pysklywec, Occupational Health Physician, and Michelle Tew, Occupational Health Nurse, Occupational Health Clinics for Ontario Workers Inc., and each event will run 90 minutes long.

Work-Related Asthma: Breathe Easier - Part 1

Wednesday, February 22, 2012 1:00 pm - 2:30 pm EST

This first webinar focuses on recognition and management of work-related asthma in the worker/patient.

  • Awareness of work-related asthma, including identifying characteristics and workplace agents

  • Management of symptoms

  • How to seek support for affected workers

Work-Related Asthma: Breathe Easier - Part 2

Wednesday, March 21, 2012 1:00 pm - 2:30 pm EST

The second webinar focuses on recognition and management of work-related asthma in the workplace.

  • Identification, reduction or prevention of workplace exposures

  • Return-to-work issues and case studies

Case studies will highlight key points and allow participants to apply lessons learned. Access to numerous free resources will also be provided. Attendees of these webinars will qualify for continuing education points.

This webinar series was developed as part of the Asthma Plan of Action, by the Ontario Lung Association, in cooperation with CCOHS and funded by the Government of Ontario.

Learn more about these webinars and register.


Psychological Health and Safetyprint this article

Mental illness is more common than you may think. A recent survey showed that half of adults in Canada are either affected by mental illness or know someone who is. Mental illness has a tremendous cost to individuals, employers and society overall. There has also been an increasing understanding of mental health issues and work/life concerns, the impact they can have on workplace performance, and how they are critical to the healthy functioning of workers and the success of organizations.

This month's Health and Safety To Go features a podcast on psychological health and safety. Merv Gilbert, Adjunct Professor at Simon Fraser University and Gerry Culina, General Health and Safety Services Manager at CCOHS, discuss the powerful and expanding impact mental health problems have on the workplace.

The podcast runs 11:40 minutes. 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.

For more information on workplace mental health, visit our website, Healthy Minds at Work.


Forum IV: Better Together - A Canadian Conversationprint this article

Registration now open for this national 2-day event

Forum IV is a two-day tripartite, national event that will bring subject experts, workers, employers, and governments into one dynamic setting, to share their knowledge and experience around the growing concern for total worker health and well-being.

Forum IV is an opportunity for participants to collaborate on integrated, comprehensive approaches to total health and wellness at work. There is a connection between the mental, physical, and psychosocial aspects of both the work and non-work environments. Injuries, illnesses, high stress levels, chronic absenteeism, low morale and dissatisfaction - all can have a devastating effect on workers, families, and organizations.

Through the key discussion topics of mental health, psychosocial work factors and musculoskeletal disorders, harassment and bullying, and integrated workplace health and safety, participants will work together towards solutions for the total health of workers, in vibrant, engaged and balanced workplaces.

Participants will take part in interactive workshops and benefit from presentations by leading workplace health and safety experts.

This will be CCOHS' fourth national forum. The most recent was held in Gatineau, QC, and brought together hundreds of participants from across Canada who shared their experiences while putting forth recommendations on how leadership can positively impact the health and safety of workers.

"An excellent opportunity to meet new people, to be exposed to new ideas … to know what challenges people from different businesses and industries face."

-- Past CCOHS Forum Participant

Visit the Forum IV website for the latest information on all the topics and speakers. Register now and save $100. Special rates for CCOHS Members and full-time students are also available.

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