Canadian Centre for Occupational Health and Safety
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>Health & Safety Report

Volume 2, Issue 2 - February 2004

In the News
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Mould has no place - in the workplace

Mould may play a practical role in the outdoors - breaking down fallen trees and leaves, however mould growth indoors, can have harmful affects on both property and the health of the people inside. Mould can gradually damage building materials and furnishings and even cause structural damage, as well as pose health risks to people in the building it invades.

A key characteristic of mould is its ability to grow without sunlight. It needs only a viable mould spore, a nutrient source, some humidity and moisture to thrive, and is often found in damp, dark and hidden spaces. Mould spores can be released into the air when mouldy material becomes disturbed. Exposure occurs when the spores are inhaled.

Generally exposure to most types of moulds does not cause symptoms in healthy people - but some moulds may be hazardous for those with allergies or other health issues. People who have asthma, bronchitis, hay fever, other allergies, uncontrolled diabetes or have weakened immune systems, are more likely to react to mould.

In addition, many of these moulds make "mycotoxins", by-products that are toxic to humans. These toxins can slowly wear down the immune system and can lead to allergic or respiratory problems.

The most common symptoms reported are runny nose, eye irritation, skin rash, cough, congestion and aggravation of asthma. People with serious allergies to moulds, may have stronger reactions that include fever and shortness of breath. People with chronic illnesses, such as obstructive lung disease, may develop mould infections in their lungs.

Prevention takes awareness and effort, but is far less daunting than mould remediation projects. A quick hint: Moulds can grow almost everywhere and on any surface providing moisture is present. Reducing indoor moisture will reduce the possibility of indoor mould.

Moisture, however, is a fact of life in almost all buildings. Changes in construction since the 1970s have resulted in tightly sealed buildings with diminished ventilation. Regardless of the age of a property, it is almost impossible to prevent water leaks and spills, which are a second common source of moisture. However, a thorough drying and/or removal of water-damaged material will prevent or limit mould growth.

Prevention efforts should include building inspections, timely maintenance and the prompt repair of all plumbing and building structure leaks.

Mould prevention tips include:

  • Identifying condensation and wet spots
  • Preventing condensation by increasing surface temperature, through insulation or increased air circulation, or by reducing humidity through repair of leaks and - depending on the outside air - ventilating or dehumidifying
  • Keeping HVAC drip pans clean, flowing properly, and unobstructed
  • Performing regularly scheduled building/ HVAC inspections and maintenance, including filter changes
  • Maintaining indoor relative humidity below 70 per cent (25 - 60 per cent, if possible)
  • Venting moisture-generating appliances, such as dryers, to the outside where possible
  • Venting kitchens (cooking areas) and bathrooms according to local code requirements
  • Providing adequate drainage around buildings and sloping the ground away from building foundations

Remediation includes identifying and correcting the conditions that permitted the mould to grow and taking steps to properly remove mould-damaged materials. The highest priority must be to protect the health and safety of the building occupants and remediators. This is particularly true if it is known or suspected that the HVAC system is contaminated, as it could spread contamination throughout the building. If the water or mould damage was caused by sewage or other contaminated water, a qualified professional should be consulted.

Remediation plans may vary greatly depending on the size and complexity of the job. As a general rule, simply killing mould, for example, with biocide is not enough. It must be removed, as the possible chemical byproducts (toxins) could be present even in dead mould.

The specific method(s) used will depend on the type of material affected and the scope of the contamination. Trained clean-up personnel should use appropriate protective equipment such as respirators and gloves during cleaning activities.

Approaches include:

Wet Vacuum
These can be used to remove water from floors, carpets, and hard surfaces where water has accumulated but should not be used on porous materials, such as gypsum board. If there is insufficient liquid present, spores may be exhausted indoors. Cleaning equipment is also important because mould spores may adhere to equipment surfaces.

Damp Wipe
Mould can generally be removed from nonporous, contaminated surfaces by wiping or scrubbing with water and household bleach and then drying the surface thoroughly to discourage further mould growth. Proper protection equipment (respirators) must be worn to avoid inhaling the fumes from the chlorine bleach.

HEPA Vacuum
HEPA (High-Efficiency Particulate Air) vacuums are recommended for final cleanup of remediation areas and for dust that has settled outside the affected area. Ensure that the filter is properly seated so all the air passes through it. Use protective equipment to change the vacuum filter and to dispose of the filter and contents in impermeable bags or containers.

Use of Biocides
The use of a biocide, such as chlorine bleach, is not recommended as a routine practice during mould remediation. In most cases, the areas cannot be truly sterilized; a level of mould spores will persist in the air similar to the level in the outside air. The good news is that the spores circulating will not cause further problems once the moisture level in the building has been corrected.

Do not use fungicides indoors if they were developed for outdoor use, such as hexachlorobenzene, organomercurials, pentachlorophenol, phthalimides, and dithiocarbamates, as they can be extremely toxic to animals and humans in an enclosed environment.

Bottom line: mould has no place indoors and must be prevented at the source - eliminate excessive moisture and dampness!

The information in this article is intended only as a summary of basic procedures and is not a detailed guide to mould remediation. It is highly recommended that experts be consulted and trained clean-up personnel be engaged to handle mould contamination.

Hazard Alerts
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Protecting those who work alone

The Government of Newfoundland and Labrador Department of Labour is taking steps to raise awareness of the hazards of working alone to help protect those who do. The government's recently released document "Working Alone, Safely Guidelines for Employers and Employees", offers thorough guidelines that spell out the many different hazards that put lone workers at risk and the steps that can be taken by both worker and employer to help ensure their safety.

Under the province's Occupational Health and Safety Act - employers must do everything reasonable to protect workers, including the creation of safe work practices. They must keep in mind the many different situations where workers work alone, and consider the hazards specific to their workplaces. Employers must develop health and safety procedures and policies that address these hazards, communicate them to the employees and ensure the practices are followed.

Working alone is a common reality for many - from convenience store clerks, to truck drivers to an isolated receptionist in a large, busy office building. Research has shown that workers in the following industries are at the greatest risk of robbery and workplace assault:

  • Liquor stores
  • Gasoline service stations
  • Jewelry stores
  • Convenience stores
  • Eating and drinking places
  • Taxis

In all cases, employers are encouraged to reduce the risk, by reducing alone time, when possible, through schedules and procedures. A number of other steps can be taken to improve worker safety. Among them:

  • Assess the hazards of the workplace. (Click the link at the end of this piece for more details).
  • Investigate incidents at the workplace, and those from similar workplaces.
  • Take corrective action to prevent or minimize the potential risks of working alone (e.g. implement cash handling procedures to reduce the amount of cash on hand).
  • Provide appropriate training and education.
  • Report all situations, incidents or "near misses" where working alone increased the severity of the situation. Analyze this information and make changes to company policy where necessary.
  • Establish ways to account for people (visually or verbally) while they are working. Establish formal check-in procedures and follow them.
  • For most lone workers, the telephone will be the main source of contact. Have a telephone close by. Use alternative means when a landline telephone is not available.
  • Ensure that a qualified person will respond immediately to signs of distress.
  • Encourage employees to request assistance from police or security services if they feel unsafe.
  • Schedule high-risk tasks during normal business hours, or when another worker is capable of helping if an emergency situation arises.
  • Position workers, where possible, in locations of highest visibility.
  • Allow the use of a "buddy system" in high-risk situations.
  • Where appropriate, use a security system such as video surveillance cameras, and mirrors. Ensure that informed consent is obtained from employees prior to use.

OSH Answers
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Preventing musculoskeletal injuries

The pains and strains are variously called repetitive motion or strain injuries, cumulative trauma disorders, overuse syndrome, even occupational cervicobrachial disorders. All describe at least some of the problem, but never fully encapsulate the entire issue. But the effects of what is more accurately called Work-Related Musculoskeletal Disorders (WMSDs) are clear. Carpal tunnel syndrome, tendonitis, thoracic outlet syndrome, and tension neck syndrome are just a few examples.

Almost all work requires the use of the arms and hands and, therefore, impacts the hands, wrists, elbows, neck, and shoulders. Work using the legs can lead to WMSD of the knees, hips, ankles, and feet. Indeed, they're recognized as causing significant human suffering as well as loss of productivity and economic burdens

With the high levels of WMSDs, and interest in the subject - WMSD related questions are second only to questions about chemical hazards at NIOSH -- heightened interest is being focused on ergonomic programs seeking to prevent this painful scourge of plant and office workers alike.

WMSDs are associated with work patterns that include:

  • Fixed or constrained body positions
  • Continual repetition of movements
  • Force concentrated on small parts of the body, such as the hand or wrist
  • A pace of work that does not allow sufficient recovery between movements

Generally, WMSDs occur as a result of a combination and interaction among the factors.

Asking workers questions about their health is one element of an effective ergonomics program for the prevention of WMSDs. A symptoms survey helps to find out when workers are experiencing any discomfort, pain or disability that may be related to workplace activities. These can then be addressed.

Hazards are best eliminated at the source. In this case, the prime source is the repetitiveness of work. Therefore, efforts should be concentrated on avoiding the repetitive patterns of work. These job redesigns may include mechanization, job rotation, job enlargement and enrichment, and teamwork. Where elimination of the repetitive patterns of work is not practical, prevention strategies involving workplace layout, tool and equipment design, and work practices should be considered.

Partner News
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Manitoba's authoritative study of workplace injuries

An exhaustive report on workplace injuries in Manitoba - a joint effort of the Workers Compensation Board of Manitoba (WCB) and Manitoba's Workplace Safety and Health Division (WSHD) -- is shedding new light on issues and areas for increased prevention.

Among the findings of the Joint Injury and Illness Statistics Report:

  • The time loss injury rate has declined from a high of 5.8 in 2000 to 5.2 in 2001 and to 5.0 in 2002. That represents a 14% reduction in the time loss injury rate
  • Manufacturing contributes 17% of all workers to the economy, but generates around 35% of all WCB claims. At 9.9 time loss claims per 100 full-time equivalent workers, it also has the highest all-injury rate among industry sectors
  • Industry sub-sectors with significantly higher time-loss injury rates than the provincial average include vehicle manufacturing (16.8%), meat processing (14.3%), metalworking (14.2%), wood manufacturing (11.2%) and trucking (9.1%)
  • Workplace fatalities (not including bystander deaths): 23 workers in 2000, 28 in 2001, and 17 in 2002 were killed as a result of exposures to acute hazards in the workplace. The WCB accepted 15 occupational disease claims in 2000, 14 in 2001, and 10 in 2002
  • In 2002, the average age of injured male workers climbed to 37, and the average age of injured female workers climbed to 39
  • More than half of all time-loss injuries are musculoskeletal injuries, with the majority being strains and sprains
  • Injuries to hands and fingers comprise a quarter of all injuries

The injury report contains three main areas: injury rates, workplace fatalities, and characteristics of injured workers and accepted claims. It will become the authoritative document on all such statistics in the province. "This joint report has a number of breakthroughs," says Minister of Labour and Immigration, Nancy Allan. "It is the first comprehensive picture of workplace fatalities in Manitoba - something that's never been created before anywhere in Canada. These statistics will allow our partners in prevention to identify the most critical areas for us to focus on." The Minister added that for the first time both the WCB and WSHD have one set of numbers to represent workplace fatalities.

The WCB and WSHD are also taking the results of the report to workers across the province. It is being used as the backbone of a new SAFE Work public awareness campaign. The first ad, launched in January, plays on the children's song, "Head and shoulders, knees and toes...' The ad, run under the SAFE Manitoba banner, targets body parts most prone to workplace injury and builds on the personal risk management model promoted in the earlier ad campaigns:

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Repeating the call for RSI Awareness

A recently released Statistics Canada study determined a growing incidence of repetitive strain injury (RSI). In 2001, approximately 10% (2.3 million) of Canadian adults were inflicted with a repetitive strain injury seriously enough to limit their normal activities. The study concluded that most of these injuries were caused by work-related activity and established a direct link between RSIs and stress.

The findings add momentum to planned advocacy for the 5th International RSI Awareness Day, which takes place February 29 - fittingly, the only "non-repetitive" day on the calendar. Workers, health and safety professionals, health care practitioners and others take this day to raise awareness about Repetitive Strain Injuries and the need to take action toward prevention, rehabilitation and compensation.

Repetitive strain injuries, also known as work-related musculoskeletal disorders (WMSDs), is an umbrella term to describe a family of painful disorders affecting tendons, muscles, nerves and joints in the neck, upper and lower back, chest, shoulders, arms and hands. These disorders can be caused by frequent or repetitive work activities, or activities with awkward postures. WMSDs are a serious occupational health concern across the world. Usually arising as aches and pains, these injuries can become crippling disorders. Prevention at the source, and effective job designs, are two main methods to combat WMSDs.

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