Keith Smith
Established Member
JasonB mentioned in the post on MDF in bedrooms I had written an article on MDF. This was written a few years ago and although a few things have changed since, the majority of the article is still current.
It's long, which is why I started a new thread.
Keith
This is a follow up to the post on MDF and Formaldehyde with a lot more info for anyone who is interested.
Warning; If you carry on to read the rest of this thread it may well put you off working with wood for life.
MDF
Large scale production of MDF started in the 1980s it is environmentally friendly, in that it uses forest thinnings and sawmill offcuts which would otherwise be of little value.
MDF is manufactured by a dry process at a lower temperature than for example hardboard, another type of fibreboard. The effect of this is that the natural glues and resins contained within the wood fibres are not activated and therefore, in the manufacturing process, bonding agents and resins need to be added .
The trend has been to use formaldehyde based resins for MDF, a practice that carried over from Particleboard technology.
Commonly Urea Formaldehyde is used but this is being replaced as there are growing concerns over its health risks.
Rumours that MDF is banned in America and/or Australia are unfounded.
Dust
All dust should be treated as potentially dangerous. Machining, particularly sanding, MDF creates a very fine dust but it is no more dangerous than other wood dusts. Different woods produce different health effects and there is good evidence that even wood from different trees of the same species can produce varying health effects. The health effects of most woods have not
been extensively studied and so little is known about some woods that it is not possible to decide if they are likely to cause a health hazard or not.
Hardwood dust is defined as a carcinogen for the purposes of the COSHH Regulations. There is increasing evidence that softwood dust may also be carcinogenic to humans.
Hardwood dust can cause nasal cancer, with a small number of woods being directly implicated (beech, oak, redwood). All hardwood dusts have a UK Maximum Exposure Limit (MEL) of 5mg/m3. This is totally inadequate as the mucociliary escalator, the throat's natural defence, is severely impaired at 2mg/m3. Dust levels must therefore be kept as low as possible.
A number of woods are irritants of the skin (Iroko, Keruing, Afromosia), the respiratory tract (Beech, Iroko, Maple) or the eyes (Yew, Teak, Satinwood). Some, such as Western Red Cedar, Iroko and Mahogany, cause allergic asthma. Some woods are poisonous, such as Yew and Oleander which can cause nausea and malaise and affect the heart.
Wood dusts, particularly hardwoods, are fairly common causes of occupational asthma and rhinitis. The latent interval from first exposure to first symptom is often several years.
Formaldehyde
One presently contentious issue is the use of formaldeyde resins in the manufacture of MDF, and the healt risks assocciated.
But it is worth bearing in mind that formaldehyde is everywhere, and occurs naturally in wood.
Presently standards require that the emission of formaldehyde, which can cause eye or throat irritations, from finished products that contain formaldehyde be less than one part per million. This standard is being adhered to by most major manufacturers prior to its legislation.
Even at a low level, exposure to formaldehyde though inhalation can cause irritation to the eyes, nose, throat and mucous membrane.
Formaldehyde can also affect the skin, leading to dermatitis, and the respiratory system causing asthma and rhinitis.
The International Agency for Research on Cancer (IARC), part of the World Health Organisation, quoted evidence that even short term exposure to formaldehyde, at far below the legal limit allowable in Britain, could cause irritation to the eyes, nose and throat.
Formaldehyde is classified in the UK and throughout Europe as a Category 3 Carcinogen. This means it is a substances which "causes concern for humans owing to possible carcinogenic effects but, in respect of which, available information is not adequate for making a satisfactory assessment." In experimental studies in rats, formaldehyde causes nasal cancer. However, there is no evidence that it has caused cancer, either nasal or other, in humans.
Formaldehyde is recognised by the Health and Safety Executive as a hazardous substance and as such has been given a Maximum Exposure Limit (MEL). The MEL for formaldehyde is 2ppm.
The US limits formaldehyde emissions from MDF to 0.3ppm (parts per million)
In Germany the exposure limit is 0.lppm,
Some board manufacturers are advertising low formaldehyde or zero formaldehyde emission boards made to the stringent German 'E1' standard. This standard is currently being reviewed by the European Union.
In the UK, board manufacturers are advertising low formaldehyde or zero formaldehyde emission boards made to the stringent German "E1" standard.
This appears to be because manufacturers feel the EC is very likely to adopt this standard in the future.
Precautions
Masks (or better still a respirator with a P3 rating) and eye protection should always be used at all times, however a mask gives only marginal protection.
Machining MDF produces tiny particles which can pass through most masks, efficient extraction at source is the best protection.
Gloves should be used, especially when sanding, to avoid formaldehyde coming into contact with the skin.
When painting it is good idea to coat the whole of the product in order to seal in the urea formaldehyde.
Wax and oil may be used as finishes but they produce a less effective barrier.
Low and Zero formaldehyde MDF
It appears that most european sourced MDF now conforms to the German E1 standard. But it is still easy to buy imported MDF, produced in plants where they have not made the investment to produce low formaldehyde board, and some suppliers don't know if their boards are low Formaldehyde or not.
MDF from Travis Perkins is produced in Scotland and the factory has been producing low formaldehyde board for 8 years.
Medite make a "ZF" Zero Formaldehyde board, they are more expensive by about 50% and is less widely available. Travis Perkins can get it to order.
Workability and physical properties are the same for "ZF" as standard board.
I mention Travis Perkins because they have hundreds of branches nationwide (even one nearish me!!) they have been very helpfull and even got their supplier to contact me and confirm their boards are Low formaldehyde.
Thanks to everyone on this forum and the ukworkshop forum for their contributions.
It's long, which is why I started a new thread.
Keith
This is a follow up to the post on MDF and Formaldehyde with a lot more info for anyone who is interested.
Warning; If you carry on to read the rest of this thread it may well put you off working with wood for life.
MDF
Large scale production of MDF started in the 1980s it is environmentally friendly, in that it uses forest thinnings and sawmill offcuts which would otherwise be of little value.
MDF is manufactured by a dry process at a lower temperature than for example hardboard, another type of fibreboard. The effect of this is that the natural glues and resins contained within the wood fibres are not activated and therefore, in the manufacturing process, bonding agents and resins need to be added .
The trend has been to use formaldehyde based resins for MDF, a practice that carried over from Particleboard technology.
Commonly Urea Formaldehyde is used but this is being replaced as there are growing concerns over its health risks.
Rumours that MDF is banned in America and/or Australia are unfounded.
Dust
All dust should be treated as potentially dangerous. Machining, particularly sanding, MDF creates a very fine dust but it is no more dangerous than other wood dusts. Different woods produce different health effects and there is good evidence that even wood from different trees of the same species can produce varying health effects. The health effects of most woods have not
been extensively studied and so little is known about some woods that it is not possible to decide if they are likely to cause a health hazard or not.
Hardwood dust is defined as a carcinogen for the purposes of the COSHH Regulations. There is increasing evidence that softwood dust may also be carcinogenic to humans.
Hardwood dust can cause nasal cancer, with a small number of woods being directly implicated (beech, oak, redwood). All hardwood dusts have a UK Maximum Exposure Limit (MEL) of 5mg/m3. This is totally inadequate as the mucociliary escalator, the throat's natural defence, is severely impaired at 2mg/m3. Dust levels must therefore be kept as low as possible.
A number of woods are irritants of the skin (Iroko, Keruing, Afromosia), the respiratory tract (Beech, Iroko, Maple) or the eyes (Yew, Teak, Satinwood). Some, such as Western Red Cedar, Iroko and Mahogany, cause allergic asthma. Some woods are poisonous, such as Yew and Oleander which can cause nausea and malaise and affect the heart.
Wood dusts, particularly hardwoods, are fairly common causes of occupational asthma and rhinitis. The latent interval from first exposure to first symptom is often several years.
Formaldehyde
One presently contentious issue is the use of formaldeyde resins in the manufacture of MDF, and the healt risks assocciated.
But it is worth bearing in mind that formaldehyde is everywhere, and occurs naturally in wood.
Presently standards require that the emission of formaldehyde, which can cause eye or throat irritations, from finished products that contain formaldehyde be less than one part per million. This standard is being adhered to by most major manufacturers prior to its legislation.
Even at a low level, exposure to formaldehyde though inhalation can cause irritation to the eyes, nose, throat and mucous membrane.
Formaldehyde can also affect the skin, leading to dermatitis, and the respiratory system causing asthma and rhinitis.
The International Agency for Research on Cancer (IARC), part of the World Health Organisation, quoted evidence that even short term exposure to formaldehyde, at far below the legal limit allowable in Britain, could cause irritation to the eyes, nose and throat.
Formaldehyde is classified in the UK and throughout Europe as a Category 3 Carcinogen. This means it is a substances which "causes concern for humans owing to possible carcinogenic effects but, in respect of which, available information is not adequate for making a satisfactory assessment." In experimental studies in rats, formaldehyde causes nasal cancer. However, there is no evidence that it has caused cancer, either nasal or other, in humans.
Formaldehyde is recognised by the Health and Safety Executive as a hazardous substance and as such has been given a Maximum Exposure Limit (MEL). The MEL for formaldehyde is 2ppm.
The US limits formaldehyde emissions from MDF to 0.3ppm (parts per million)
In Germany the exposure limit is 0.lppm,
Some board manufacturers are advertising low formaldehyde or zero formaldehyde emission boards made to the stringent German 'E1' standard. This standard is currently being reviewed by the European Union.
In the UK, board manufacturers are advertising low formaldehyde or zero formaldehyde emission boards made to the stringent German "E1" standard.
This appears to be because manufacturers feel the EC is very likely to adopt this standard in the future.
Precautions
Masks (or better still a respirator with a P3 rating) and eye protection should always be used at all times, however a mask gives only marginal protection.
Machining MDF produces tiny particles which can pass through most masks, efficient extraction at source is the best protection.
Gloves should be used, especially when sanding, to avoid formaldehyde coming into contact with the skin.
When painting it is good idea to coat the whole of the product in order to seal in the urea formaldehyde.
Wax and oil may be used as finishes but they produce a less effective barrier.
Low and Zero formaldehyde MDF
It appears that most european sourced MDF now conforms to the German E1 standard. But it is still easy to buy imported MDF, produced in plants where they have not made the investment to produce low formaldehyde board, and some suppliers don't know if their boards are low Formaldehyde or not.
MDF from Travis Perkins is produced in Scotland and the factory has been producing low formaldehyde board for 8 years.
Medite make a "ZF" Zero Formaldehyde board, they are more expensive by about 50% and is less widely available. Travis Perkins can get it to order.
Workability and physical properties are the same for "ZF" as standard board.
I mention Travis Perkins because they have hundreds of branches nationwide (even one nearish me!!) they have been very helpfull and even got their supplier to contact me and confirm their boards are Low formaldehyde.
Thanks to everyone on this forum and the ukworkshop forum for their contributions.
