Support and Safety Measures...
Explosion & Fire Hazards |
Health Hazards |
Supervision & Maintenance |
Fire Protection |
Working of OP |
- Organic peroxides should be
brought into the manufacturing area in the original shipping
containers. Opened containers should not be returned to
primary storage. Material that has not been used should not
be returned to the original container. Containers of organic
peroxides should be securely closed to prevent contamination
when not in use. Opened containers of Dibenzoyl Peroxide
containing water as a phlegmatizer such as hydrous Dibenzoyl
Peroxide or many pastes and slurries must be promptly closed
to prevent drying of the material which will result in a
large increase in hazard.
- No secondary or loose
storage of organic peroxides should be permitted in the
manufacturing area. The material brought into this area
should be limited to the requirements for immediate use.
Organic peroxides should be removed from the manufacturing
area and placed in the weighing and dispensing room each day
at the close of business.
- Areas where organic
peroxides are handled should be well ventilated and
sprinklered. Appropriate protective clothing, such as rubber
gloves, safety glasses, goggles or face shields should
always be worn to avoid bodily contact from inadvertent
splashing or spills.
- When organic peroxides are
poured into mixing dispensing containers, care should be
taken to provide clean and properly designed equipment.
Copper, brass, mild steel or lead equipment is dangerous in
contact with organic peroxides. Zinc and galvanized
equipment can also cause accelerated decomposition of
organic peroxides. The use of compatible type equipment with
each organic peroxide is essential. (Consult the
manufacturer or supplier of organic peroxides for
recommended materials to be used.)
- Where it is necessary to
slurry, mix, or dissolve organic peroxide in very small
quantities of monomer (such as styrene) prior to
incorporating the material into the resin mix, the peroxide
should be added to the monomer and used promptly. These
"small quantity" mixtures are polymerizable and they may
develop considerable heat. This could be sufficient to boil
the solvent monomer and cause it to ignite.
- Dilution of organic
peroxides by users is not recommended. Notwithstanding the
recommended practices, it is known that some composite
producers do dilute MEK peroxide. In this instance, the
following instructions should be followed: Be sure to
consult with the peroxide manufacturer for compatible
solvents. Use only high purity solvents. Never use
contaminated solvents. Never use reclaimed solvents unless
they have been specifically tested by the organic peroxide
manufacturer. The use of an incompatible or contaminated
solvent may cause a violent decomposition of the organic
- The fire hazard of an
organic peroxide can be drastically changed by the diluent
employed. The fire hazard can be increased by using a low
flash point solvent, such as ethyl acetate, or decreased by
using a high flash point plasticizer such as dimethyl
- Organic peroxides should
not be used in pressurized vessels or confined unless
adequate provisions have been made to relieve the sudden
pressure that may develop if the peroxide is decomposed by
heat or contamination. Organic peroxide may be released
during venting and provisions should be made for the
protection of personnel and the possibility of fire.
- Mechanical processing, e.g.
"Spray Up" Equipment, should be given special consideration.
Keep this equipment very clean and scrupulously avoid
contaminating the organic peroxide when filling the
dispensing containers. Protect dispensing containers from
fire and all sources of heat. Pressurized dispensing
containers should comply with item 8. Strictly observe
dilution instructions (item 6). When testing, spray organic
peroxide solutions into a container of water. Do not spray
into the air, on resin overspray, etc. Wear protective eye
equipment at all times.
- Organic peroxides should
never be mixed directly with any accelerators or promoters,
as violent decomposition or explosion may result. The
accelerator should be thoroughly dispersed in the resin
mixture before adding the peroxide catalyst.
- Organic peroxides should be
kept away from all sources of ignition, such as open flames,
electrical devices and heating equipment.
- All processing equipment
should be properly grounded and inter-bonded. Non-sparking
tools should be used for weighing the peroxides.
- Solid organic peroxides
should not be subjected to any frictional or grinding
- Organic peroxides should
not be added to materials at temperatures exceeding safe
tolerances for the particular peroxide.
- "No smoking" regulations
should be strictly enforced in the organic peroxide storage
and processing area . No matches, open lights or flame
should be permitted in this area.
Handling of organic peroxides
Organic peroxides must always be handled by skilled personal, wearing
appropriate equipment: goggles, gloves, a face mask and a helmet should be worn
whenever handling peroxides.
Peroxides are formulated to reduce risks. However, these safety formulations
remain sensitive and must be handled with care.
Classification and labeling depend on product properties and are described in
the safety data sheet according to the Directive 67/548/EEC and its amendments.
The relevant symbols and Risk and Safety phrases are on the label.
In addition to this labeling (according to the European Directive), each package
is also identified by the yellow N°5.2 "Organic Peroxide" warning symbol.
Handling procedures should be set up to ensure that peroxides are
protected from sources of heat such as hot ambient air, radiators, pipes, direct
sunlight, sparks and flames. The recommended storage temperature should be
observed at all times. Smoking must be strictly forbidden.
At the work place, only the minimum quantity of peroxide required for one
operation should be stored. Return of unused organic peroxide to the original
container is not allowed due to risk of contamination. The material must be
Dispensing and weighing
should be done in a specially designated area and should not be permitted in the
Spilled materials should be soaked up immediately on an inert absorbent
such as Vermiculite or Perlite. The contaminated Vermiculite should be taken up
by non sparking equipment and disposed of according to local regulations.
The place where the spillage occurred should then be cleaned with water
containing a surfactant to guarantee that no traces of peroxide to be left.
Packaging is chosen in accordance with the characteristics of the organic
peroxide. For transportation, only approved packaging material may be used;
moreover, the maximum quantity of peroxide per packaging unit is given by
When peroxides are transported or when they are stored during a long period,
pressure can build up within the container due to a small amount of
decomposition or volatility of a component in the peroxide formulation.
Polyethylene is therefore the preferred packing material since it is relatively
inert, is flexible enough to withstand normal pressure build-up.
Peroxides should not be kept in glass or metal vessels where a built up of
pressure by decomposition cannot be noticed.
Organic peroxides must be kept in their original containers, as every contact
with rust, ashes, dirt, accelerators, promotors and many chemicals can lead to a
Storage regulations vary from one country to another and it is essential to
check with local
authorities and insurance companies on specific regulations.
In most cases, the regulation (if one regulation exists) defines:
classification group depending on the hazard involved (flammability,
decomposition, burning, or explosive properties)
The requirements for the storage construction. These specific classifications
are available on request (our peroxides are classified according to all
existing European regulations).
However, the following requirements must be applied in all cases. More
specific information is given in your local regulation.
A peroxide storage facility should be:
Located away from the manufacturing area: the hazards linked to the storage of
peroxides involve effects outside of the storage building and required safety
distances. The minimum safety distances required by local regulations vary
according to the countries.
Used exclusively for organic peroxides to avoid contamination.
Built with construction material according to local -regulations.
Equipped with specific electrical installations (explosion proof), heating and
Kept under controlled temperature conditions: the maximum storage temperature
must not be exceeded and temperature alarms must be installed
Provided with vent relief system, fire protection equipment (water sprays,
Equipped with retaining basins to prevent accidental discharge to the
Clearly identified as "peroxide storage" and marked outside "No smoking".
Recommendations to avoid accidents
What to do before delivery of a peroxide?
Check if the safety data sheet is available.
Read it carefully.
Check the required storage temperature.
Read the storage requirements.
What to do on
Check if the storage building is at the required temperature.
Mark each container with delivery date.
Check if the delivered product is at temperature below the required one. If
not, the transportation was incorrect. If temperature of the product is above
SADT, don't put in storage with other products.
Check carefully the packages to avoid leakage and spillage.
How to store the product
Respect an air cooling circulation of ~ 5 cm between each package and ~ 30 cms
with the walls.
Always verify that the door of the storage is closed.
Avoid leaving the door open during long periods.
Respect the amount allowed in storage.
If the refrigeration system fails
The failure is easy to detect in a well built storage (temperature alarm...) and
the time before an accident is long enough to implement preventive measures:
refrigeration back up, transfer in another storage.
How to dispose of the product?
Disposal must be accomplished in accordance with local regulations.
Small quantities of organic peroxides that are spilled or became contaminated,
or any samples
no longer needed should be destroyed.
Spilled solid peroxides should be carefully swept together, collected into
suitable labeled container, and destroyed.
Large quantities of organic peroxides must be handled and disposed of
Peroxide formulation should be diluted in mineral oil or fuel oil to an active
oxygen content of less than 1% and then be burnt in an incinerator. This must be
done in accordance with the local legislation.
What can we do with the empty containers?
They have to be emptied completely and must also be transported as dangerous
goods. Following local regulations, some answers may be given by your supplier.
Safe use and Handling of Organic peroxide initiator
1. Know the storage temperature and do not exceed it.
2. Know the SADT "Danger Temperature" and respect it.
3. Equip storage area properly.
4. Have fire extinguishers available.
5. Rotate inventory: "First In, First Out".
6. Take only the amount that will be used.
7. Do NOT return unused initiator to storage buildings.
8. Rinse and slash containers prior to disposal.
9. Immediately clean up spills and dispose of them properly.
10. Protect your eyes and skin.
11. Use appropriate Personal Protective Equipment (PPE).
12. Initiator in large vessels should be diluted.
13. Know your plant's emergency procedures.
Above all, when it comes to storing, handling and using organic peroxide
"Don't Lose Your Cool!"
For additional information consult the Material Safety Data
Organic peroxides can generally be considered as having a moderate toxicity.
The main effects associated with contact with organic peroxides are local
irritations, burns of the skin, and mucous membranes: of the eyes and of the
Inhalation of the vapor of volatile peroxides also leads to irritation or burns
of the mucous membranes of the eyes and the respiratory
Why use organic peroxides in
Unsaturated polyester is a family of thermosets with many uses such as in engine
parts, covers, electrical terminal boxes, swimming pools, boats, tanks and so
Polyester resins are generally associated with fillers (Silica, CaCO3), glass
fibers, glass fibers mats or fabrics acting mainly as a binder.
There are two main processes:
- Cold process
- Hot process (Sheet
molding compound (SMC), Bulk molding compound (BMC))