SECTION 2.2 INCIDENTS INVOLVING BROMINE CONTAINERS

2.2.1   Container Assessment

  • From a distance, perform a visual inspection of the container looking for evidence of damage, leaks or staining
  • Be sure to put on the correct personal protective equipment for closer inspections or before taking steps to repair suspected damage or leaks.
  • Inspect the gasketed fittings under the container dome which are more susceptible to leaks.  
  • If possible, utilize the guidance provided in this document to repair any active leaks associated with the fittings (See Section 2.3).
  • If wet stains or residues are noted, clean the container using neutralizing solutions (see Section 2.2.4) followed by a water rinse. 

2.12.2       Small Spills - General Advice

Small spills from a small package or small leak from a large package

  1. Call the emergency response number on the shipping papers first.  If there is no answer, dial the appropriate phone number provided in section 2.1.
  2. As an immediate precautionary measure, isolate a bromine spill and leak area in all directions for at least 60 metres.
  3. Consider taking steps to protect people downwind of the bromine spill through evacuation.  For daylight hours the protection can extend up to 0.6 km downwind from the spill.  During night-time the protection zone can extend up to 1.8 km.
  4. Keep unauthorized personnel away.  If possible, isolate the container with barriers.
  5. Stay upwind and keep out of low lying areas.
  6. Only trained chemical emergency responders should be allowed to clean up the spill.
  7. Professional responders should always wear correct personal protective equipment when dealing with a bromine spill.
  8. Responders should always work in pairs.
  9. Neutralising chemicals should be in small quantities incrementally as needed (i.e - do NOT dump large amounts of neutralising chemicals onto spilled bromine all at once).
  10. Wash the container afterwards using a brush and neutralizing solution followed by a water rinse.

2.2.3       Large Spills – General Advice

Large spill from a large package or many small packages

  1. Call the emergency response number on the shipping papers first.  If there is no answer, dial the appropriate phone number provided in section 2.1.
  2. As an immediate precautionary measure, isolate a bromine spill and leak area in all directions for at least 300 metres.
  3. Consider taking steps to protect people downwind of the bromine spill through evacuation.  For daylight hours the protection can extend up to 3.1 km downwind from the spill.  During night-time the protection zone can extend up to 6.6 km.
  4. Keep unauthorized personnel away.  If possible, isolate the container with barriers.
  5. Stay upwind and keep out of low lying areas.
  6. Only trained chemical emergency responders should be allowed to clean up the spill.
  7. Professional responders should always wear correct personal protective equipment when dealing with a bromine spill.
  8. Responders should always work in pairs.
  9. Neutralising chemicals should be in small quantities incrementally as needed (i.e - do NOT dump large amounts of neutralising chemicals onto spilled bromine all at once).
  10. Wash the container afterwards using a brush and neutralizing solution followed by a water rinse.

2.2.4   Personal Protective Equipment

Standard clothing during a bromine accident without liquid spill or vapour leak

  1. Safety shoes
  2. Safety helmet
  3. Work gloves
  4. Overalls
  5. Safety glasses

Standard protective equipment when container assessment indicates only a small bromine vapour leak (only a small amount of vapours; no liquid present; for example, a leak from an open vapour valve)

  1. Full face mask with ABEK/P canister or positive pressure self contained breathing apparatus (SCBA)
  2. PVC/Neoprene suit
  3. Pair of PVC/rubber boots
  4. Neoprene, nitrile or other bromine resistant gloves

Standard protective equipment when container assessment provides strong indication of a liquid bromine spill or large amounts of bromine vapours present (large visible vapour clouds or other indications of large vapour leak; evidence of standing liquid bromine; evidence of bromine egress into soil or water ways)

  1. Bromine resistant gas tight suit (level A responder suit)
  2. Positive pressure SCBA, fully encapsulated

Notes:

  • Wear chemical protective clothing that is specifically recommended by the manufacturer for bromine service.  Note that chemical protective clothing will generally provide little or no thermal protection.
  • Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with a chemical substance, including bromine, is possible. 
  • Chemical responders and personal protective equipment that have been exposed to bromine and its vapors should be fully decontaminated prior to equipment removal. 
  • When in doubt about the level of bromine vapours present, the highest level of PPE protection should be utilized  


2.2.5 Neutralisers for Bromine

There are a wide variety of chemicals that can be used to neutralize bromine.  A summary of commonly available neutralising materials appear in the table below.  In an emergency situation, where time is of the essence, an available neutralizing chemical, even if less preferred, may be the best option for use.  For instance, though sodium thiosulfate is less preferred than other options for a variety of reasons, it may still be the best option if it is already at the scene and slake lime or soda ash will not be available for another hour.

 

Bromine Neutralizing Agents - Summary Table 

 

 

Slaked Lime [Ca(OH)2]

Slaked lime (solid) is recommended because it:

  • is usually readily available (it can be found in home and garden shops as garden lime
  • can be used to form a dike around a bromine spill
  • will adsorb the bromine. 

Slaked lime will only begin to react with bromine when water is added.

The balanced equation for the neutralisation reaction is as follows:

6Ca(OH)2 + 6Br2 --> Ca(BrO3)2 + 5CaBr2 + 6H20

A 20% - 40% slaked lime water slurry can be used.

Procedure for use

  1. Form a dam of solid slaked lime around the bromine spill
  2. Adsorb the bromine in the slaked lime and mix with a shovel or other suitable device
  3. Slowly add water to a small amount of the mixed solids to activate neutralisation
  4. mix water/bromine/slaked lime mixture thoroughly using a shovel or other mixing aid
  5. Proceed incrementally in a step-wise manner by repeating steps 2 - 4 until all the bromine is neutralized
  6. Collect the neutralised materials for further remediation at an approved site.

Sodium carbonate (soda ash) slurry

Sodium carbonate can be used as a 35% suspended solution, as a solid or as a dissolved solid .

In order of preference:

35% solution >> solid > dissolved.

3Na2CO3 + 3 Br2   --->  NaBrO3 + 5NaBr + 3CO2

  • 1,3 kg sodium carbonate destroys 1 kg of bromine.
  • Heat of Reaction: 14.2 Kcal/mole Br2 (endothermic).
  • 10 - 30% potassium carbonate solution can also be used if more readily available.

Suspensions at concentration of more than 35% should not be used. The desired weight ratio between suspension and bromine is 1:1 to 1:2.

The neutralisation of bromine with sodium carbonate suspension yields products containing about 40% reacted bromine.

It is important to note that the reaction between soda ash and bromine will release large volumes of CO2 gas.  CO2 gas may increase bromine fumes if it percolates through the liquid bromine

 

Caustic (Sodium hydroxide 5 - 10%)

In an area where the spillage has been contained, a 5% to 10% solution of caustic soda is sometimes used but is not recommended. Sodium bromate can form, which is an oxidising agent and can be explosive under some conditions.

6NaOH + 3 Br2 ---> NaBrO3 + 5NaBr + 3H2O

Heat of Reaction: - 10.8 Kcal/mole Br2 (exothermic)

 

Sodium thiosulfate (sodium hyposulfite)

A solution of 40% sodium thiosulphate (hyposulphite) in water containing 1% soda ash [Na2(CO3)2] can also be used. The solution has limited shelf life.

Sodium thiosulphate has a very high heat of reaction and should only should be used for neutralising small quantities

2Na2S2O3 + Br2 ---> Na2S406 + 2NaBr

Roughly 1 kg sodium thiosulfate will destroy 1 kg bromine.
The solution is made of the following components:

  • 90 kg sodium thiosulphate.
  • 2,5 kg sodium carbonate (Na2CO3).
  • 200 L water.

CAUTION! - Bromates (Br03-)

Bromates can form during some neutralisation reactions and may need to be removed.  Bromates are strong oxidising agent.  Dried bromates can be shock sensitive and consequently may explode under some conditions.

Neutralisation streams containing bromates will generate bromine and bromine vapours if acidified.  A 10 - 30% sodium thiosulfate (aqueous) solution or an aqueous sodium bisulphite solution can be used to reduce bromates to their corresponding bromide salt.  Reactions to reduce bromates to bromide are highly exothermic. 

Anhydrous Ammonia gas (Vapours only)

Anhydrous ammonia gas can be used to assist chemical responders in significantly reducing bromine vapours in a spill situation.  This technique is for trained responders only.  Anhydrous hydrogen bromide is itself flammable and hazardous and careful consideration must be given prior to use in a given situation.

The salt forming reaction is exothermic.  Too much heat development will cause the formation of explosive intermediates.  Do not pour liquid ammonia on a bromine leak as a violent reaction may occur.

8NH3 + 3Br2 ---> 6NH4Br + N2

One kilogram of NH3 will react with about 4 kg Br2.

 

Ammonia Solution

A 10-25% ammonia solution in water reacts with bromine in an alkaline environment.  Anhydrous ammonia is a strong irritant for the skin, eyes and respiratory tract. It has a characteristic sharp, penetrating odour and is flammable.
25% ammonia reacts with bromine per the following equation:

3Br2 + 8NH4OH ---> 6NH4Br + 8H20 + N2

 

Stock

It is recommended that a bulk bromine user keep about two tons of bagged slaked lime [Ca(OH)2] or bagged soda ash [Na2CO3] on site. If the potential for a major emergency exist, provisions that would allow supply of as much as about 20 tons of bagged slaked lime or bagged soda ash should be considered.

Stored neutralizing materials should be protected against weather damage and replaced periodically after caking.

An additional source of neutralizing materials within a reasonable distance from the site should be available on short notice.


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