Section 13 - An Industry Study Study – Wood & Wood Products

Woodworking Machine Safety

Controlling Wood Dust Inhalation

Avoiding Exposure to Chemicals

Handling Wood Components & Products

Avoiding Exposure to Excessive Noise

Reference Materials & Resources

SPECIFIC INDUSTRIES
Wood and Wood Products
Welcome to the health and safety resources on-line for businesses in the wood and wood products industry. The resources in this section are designed to help you address common health and safety issues that are significant within this industry.

For information on hazards that are common to all businesses see Hazards and Solutions. Those who are new to occupational health and safety should look at Getting Started
With a Health and Safety Program. If you are interested in the benefits to your business from better health and safety, read Better OHS - Good for Business.

 Woodworking Machine Safety

Common Accidents

Even where machine guarding is in place the risk of injury in using woodworking machinery is not eliminated. Some common injuries include:

Cut hands while planing and moulding.
Wood kicking back or flinging upwards, striking the machinist.
Wood of a jig breaking and injuring the machinist.
Injuries from clearing  wood or sawdust while the machine is running.

Solutions
All machines should be guarded according to Australian Standards for Woodworking Machines.

General Safety Precautions
The risks associated with operating woodworking machines can be reduced by the following safe work practices.

Machines
Use mechanical feeding wherever possible.
Maintain machines and guards on a regular basis not just when there is a problem.
Ensure adequate lighting.
Ensure that emergency stop buttons are clearly identified and signed.
Ensure that machines are switched off and isolated when not in use or when being cleaned.
Ensure that unauthorised persons cannot access machine areas.

Operators

    1. Wear clothing that will not become caught in machinery.
    2. Keep list of Operator competency reviews for each machine. Review operators' competency to operate the machine annually and record date of review.
    3. Ensure that eye protection is worn.
    4. Ensure operators' conduct daily Pre-Use Inspections of their machines checking critical parts. For example, checking saw settings, condition of guards, blades, bolt heads, spindle nuts correctly tightened.

Controlling Wood Dust Inhalation

Effects of exposure to wood dusts

Wood dust produced by machining or sanding may be irritating to the eyes, respiratory system
and skin. It may cause sensitisation by inhalation and skin contact. Prolonged exposure to wood dust may cause nasal and nasal cavity cancer by inhalation, Particular care should be taken when machining preservative-treated wood because of possible health effects from the added chemicals. Refer to the Material Safety Data Sheet for that product.

In 1995 the International Agency for Research on Cancer (!ARC), which is an agency of the World Health Organisation, evaluated the cancer risks associated with workplace exposures in a variety of wood industries. The !ARC classified wood dust as a Group 1 carcinogen to humans, This classification is the result of a marked increase in the occurrence of cancer of the nasal cavities and paranasal sinuses among workers exposed to hardwood dust.

The best way to control dust inhalation is by the use of properly designed and maintained dust extraction systems.
In addition to dust extraction equipment, work areas should be well ventilated. In the absence of dust extraction an approved dust mask in conformance with the requirements of Australian Standards 1715 and 1716 should be used.
At all times wear eye protection as prescribed by Australian Standard 1337.

The wood dust produced when machining MDF and hardboard is finer and more readily dispersed into the surrounding air than the dust from most solid wood, plywood or particleboard.

In this respect, these dusts are similar to the wood dust produced when sanding finely textured hardwoods, with both requiring a higher level of extraction efficiency.

For wood dust from pine timber particleboard, dust extraction systems require a minimum capture velocity of 10 to 20m/sec, compared with 20 to 30 m/sec for wood dust from MDF, hardboard and some hardwoods.

The higher capture velocity required for these finer wood dusts can often be met by simple modifications to existing equipment. For example reducing the size of the collector hood openings and placing them as close as practicable to the point of dust collection will assist in raising capture velocities.

Collection efficiency will also be improved by closing off ducts connected to machines which are not in use subject to maintaining the recommended minimum air velocity in the remaining ducting.

For fine wood dusts, such as that from MDF, the air velocity in the ducting needs to be 15 to 20 m/sec to prevent an accumulation of dust (plugging) which could  cause a fire risk. 

High concentrations of wood dust, particularly from sanding, can form explosive mixtures with air. It is recommended that ducting should be fitted with explosion vents.

For large extraction systems, the fitting of spark detectors and automatic extinguishing equipment is advisable. In addition, electric motors should be spark proof.

Wood dust which gathers on the floor, on ledges, in machinery pits, etc. should be removed by suction devices or wet sweeping. Use of compressed air should be avoided. If it is used, the person using the compressed air should wear a suitable dust mask or respirator in conformance with the requirements of Australian Standards 1715 and 1716.

Some woods and wood dusts can contain naturally occurring chemicals which may cause sensitisation in some people, for example, in the form of dermatitis and asthma.

Protective clothing

In particular, long shirt sleeves and gloves should be worn at all times to avoid skin contact. Remember to wash soiled clothing and do not shake off the dust.

Avoiding Exposure to Chemicals
Timber Finishes                                                                 
Many of the finishes applied to wood and wood products, such as paints, lacquers and varnishes, contain solvents, bacteriacides and other chemicals which may have possible health effects.

It is important that all such materials be checked. to ensure their safe use:

    1. First, obtain a Material Safety Data Sheet from the supplier or manufacturer prior to purchase.
    2. Second, examine the labels on the container for information about possible health effects and how to avoid them.

The above precautions apply not only to paints, lacquers, or varnishes but equally to adhesives and other chemicals used in the industrial environment.

Documentation such as labels and Material Safety Data Sheets are not designed to scare people but to ensure that any potential hazards associated with the material are known and the handling procedures for safe use are detailed.

Formaldehyde

Wood panels such as particleboard, medium density fibreboard and plywood, laminated veneer lumber and laminated beams which utilise formaldehyde-based adhesives may emit small amounts. of formaldehyde into the air.

Research has indicated that generally, the amounts of formaldehyde emitted are well below the National Occupational Health and Safety Commission's exposure standard for formaldehyde of 1 part per million (ppm).

However, unacceptable exposure levels could occur when large quantities of product are stored in a confined, poorly ventilated space or when plastic wrapping is removed from newly manufactured material.

The solution is to improve air circulation and ventilation to the affected area.

Handling Wood Components and Products

Effects of unsafe handling practices

Strain injuries of the muscles and ligaments can occur through overexertion or continuous overuse when undertaking activities involving lifting, carrying, holding, pushing and pulling. Injuries can be sudden or occur over a long period of time.

The safest way to handle wood components transportation is by automated or mechanical means. Where this is not possible, safe working practices, such as team lifting, are strongly recommended.

For lifting, lowering or carrying loads the following guidelines from the Code of Practice are appropriate:

    1. In seated work, it is advisable not to lift loads in excess of 4.5kg;
    2. Some evidence shows that the risk of back injury increases significantly with objects above the range of 16 - 20kg. Therefore from the standing position, it is advisable to keep the load below or within this range. Mechanical assistance and/or team lifting arrangements should be provided to reduce the risk of injury associated with these heavier lifts.
    3. Generally, no person should be required to lift, lower or carry loads above 55kg unless mechanical assistance or team lifting arrangements are provided to lower the risk of injury.
  1. Avoiding Exposure to Excessive Noise

What is excessive noise?
Noise is measured in decibels (dB). The maximum permitted workplace noise exposure level to which a person can be subjected is typically 85dB(A). Local regulations should be checked with the government department responsible for administering health and safety in your State or Territory.

Even if the level of noise is below that which might damage hearing, it can contribute to other dangers by masking warning signals and hindering communication. It also contributes to operator fatigue. The need to wear hearing protection when noise levels would otherwise damage hearing creates similar problems. As a result, noise reduction techniques can pay off by improving safety as well as conserving hearing.

Wherever possible, excessive noise levels should be reduced by engineering controls such as:

Modifying existing noisy machinery through design changes.

  1. Replacing noisy machinery by installing newer equipment designed for operating at lower noise levels.
  2. Isolating the source of the excessive noise from all persons not involved with the operation of the equipment.

Any person receiving noise higher than that permitted should wear personal hearing protection in the form of earmuffs or earplugs. These should conform to Australian Standard 1270.

For more general information on managing noise in the workplace refer to noise in Hazards and Solutions section.

Reference Materials and Resources

Wood Product Safety Information Kit
National Association of Forest Industries

Risk Control Manual for Log Sawmilling
Victorian Association of Forest Industries

AS/NZS 1473  Series  -  Guarding  of  Woodworking  Machinery (currently being drafted into three parts for relevant industry sectors) Standards Australia

National Industry Competency Standards for the:

  1. Sawmilling and Processing Sector of the Forest Industries
  2. Manufacturing and Merchandising Sector of the Forest Industries

Forest and Forest Products Employment Skills Company.