Carson Ph., Mumford C. Hazardous Chemicals Handbook (Справочник по опасным химическим веществам)

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First aid

In Great Britain the Health and Safety (First Aid) Regulations 1981 require an employer to

provide such equipment and facilities as are adequate and appropriate in the circumstances to

enable first aid to be rendered to his employees if they are injured, or become ill, at work. An

Approved Code of Practice gives more specific details on the number of first-aid personnel and

their training, and the type of equipment.

Emergency first aid

A qualified first-aider, or nurse, should be called immediately to deal with any injury – however

slight – incurred at work.

Any person on the spot may have to act immediately to provide first-aid treatment to prevent

deterioration in the injured person’s condition until assistance arrives. The aims are:

• To sustain life.

• To minimize danger.

• To relieve pain and distress.

Check the situation for danger to rescuers, then act as follows:

The patient: is in danger Remove from danger, or remove the danger from

the patient

is not breathing If competent to do so, give artificial ventilation.

Otherwise send for help without delay

has no pulse Start cardiac compressions

is bleeding Stop bleeding

Table 13.7 Procedure to treat spillages in a laboratory

Instruct others to keep a safe distance

Remove contaminated clothing and wash the hands before putting on protective clothing

Shut off all sources of ignition (for spillage of flammable fluid); do not operate electric switches in the vicinity

Ventilate the area well (for at least 10 min) to reduce irritant vapours and biological aerosols, and to evaporate remaining

liquid (bear in mind that ventilation may transfer the danger to other parts of the premises)

Areas with sealed windows should have controlled ventilation (areas that cannot be adequately ventilated are unsuitable for

use with hazardous materials)

Turn off the source of the leak and limit the spread of fluid by means of mop, dusters, rags, sand or diversion

Absorb spillage and shovel into buckets, and remove to a safe place, dilute greatly with running water and/or dilute with

dispersing agent and water (as with ammonia solution, ethanol, methanol and formaldehyde solution)

Neutralize acid with soda ash, chalk or similar materials kept for the purpose, mop up cautiously with water (in case local

areas of concentrated acid have been missed)

Use hypochlorite solutions in excess scattered over spillage of cyanide solutions and wearing respirator and gloves, mop up

and collect in buckets. Allow to stand for 24 hours before diluting greatly and running to waste

Flood with a phenolic disinfectant any biologically contaminated area for 30 to 60 min and then clean up with water and

allow to dry. After cleaning up wash hands with a suitable skin disinfectant (such as 0.5% Chlorhexidine in 70%

methylated spirit)

Use forceps or a brush and pan with broken glass; never use the fingers, even with gloves. Disinfect broken glass arising from

biological spills

Dispose of, by special arrangements, chemicals which cannot be admitted to the public sewerage system, e.g. flammable

liquids and reagents with high toxicity

FIRST AID 429

430 OPERATING PROCEDURES

is unconscious Check the mouth for any obstruction. Open the

airway by tilting the head back and lifting the

chin using the tips of two fingers. If this does

not keep the airway open, turn the casualty into

the recovery position i.e. turn on side and ensure

they cannot roll over; lift the chain

feels faint Lie him or her down

has broken bones Immobilize. Do not move the patient unless he/

she is in a position which exposes them to

immediate danger. Obtain expert help

has open wounds After washing your hands, if possible cover with

a dressing from the first-aid box. Seek appropriate

help

has thermal or chemical burns Immerse or flood copiously with cold water for

≥10 min

has minor injuries Ignore these if there are more serious ones

is poisoned Small amounts of water may be administered,

more if the poison is corrosive. Administer a

specific antidote if one exists. Do not induce

vomiting.

Cuts

All minor cuts should be cleaned thoroughly and covered with a suitable dressing. After controlling

bleeding, if there is a risk of a foreign body in the wound do not attempt to remove it, but cover

loosely and take patient to a doctor or hospital, as should be done if there is any doubt about the

severity of the wound.

Burns/scalds

Burns may arise from fire, hot objects/surfaces, radiant heat, very cold objects, electricity or

friction. Scalds may arise from steam, hot water, hot vapour or hot or super-heated liquids.

The affected area should be cooled by holding in cold, clean running water. Swelling is liable

to occur so jewellery or clothing likely to cause constriction must be removed. The area should

then be covered with a sterile dressing, care being taken to apply the dressing without it sticking to

the burned area. Blisters should not be pricked or damaged and cream or lotions should be avoided.

The patient may suffer from shock, in proportion to the extent of the injury. Give small drinks

and keep warm: do not overheat. In all cases, speed of treatment is crucial to limit the effects of

burns. Flowcharts which summarize the initial procedures for electrical, thermal and chemical

burns respectively are shown in Figure 13.5.

Chemical splashes, poisoning by ingestion

Refer to Table 13.8.

All cases of ingestion should be referred to a doctor and/or hospital without delay.

Antidotes

Effective antidotes for use in an emergency are not common. Examples include:

* Material Safety Data Sheets should accompany casualty in every case.

Chemical burns

Protect yourself with rubber gloves, etc.

Identify, but do not try to neutralize, the chemical

Remove casualty from danger

Wet chemicals

Dry chemicals

Carefully brush off chemical

Remove contaminated clothes, jewellery,

boots, etc.

Wash/shower all affected areas with

water for at least 10 minutes

Do not use ointments

Seek medical attention*

Work’s medical

centre

Own GP Hospital casualty

Thermal burns

Remove casualty from heat or cold

Wash/shower all affected areas with water for

at least 10 minutes

Minor –

simple burns

Major

• large, deep

• other injuries

Continue with cold

water until pain stops

Seek urgent

medical attention

Advise casualty to seek

medical attention

Work’s medical centre

Own GP Hospital casualty

Do not use

ointments

Turn off power or isolate casualty from current

Electrical burns

Treat for thermal burns – more than one

burn site may be present

Always refer for immediate medical assessment

Work’s medical centre

Hospital casualty

Figure 13.5

Initial procedures for dealing with burn injuries

(a) (b)

(c)

FIRST AID 431

432 OPERATING PROCEDURES

• for cyanide poisoning. Intravenous injection of:

– 3% Sodium nitrite and 50% sodium thiosulphate.

– Cobalt EDTA.

• for HF on the skin. Application of magnesium oxide paste with injection of calcium gluconate

below the affected area.

• for splashes of phenols. Apply alcohol-soaked swabs.

Where there is a specific antidote suitable for emergency use it should be kept available and

appropriate personnel trained in its use. Specific training should be given to first-aiders over and

above their general training if they may need to administer oxygen or deal with incidents involving

hydrogen cyanide, hydrofluoric acid or other special risks.

Table 13.8 Standard first aid treatments for chemical exposure

Splashes on the skin Flood the splashed surface thoroughly with large quantities of running water for

≥10 min or until satisfied that no chemical remains in contact with the skin

Use soap to help remove splashes of solvents, solutions and chemicals known

to be insoluble in water

Remove all contaminated clothing, taking care not to contaminate yourself in

the process

If necessary, arrange for transport to hospital or refer for medical advice to

nearest doctor

Information to accompany the casualty:

Chemical involved

Details of treatment already given

(

Special procedures apply to certain chemicals, e.g. anhydrous hydrogen fluoride,

aqueous hydrofluoric acid, phenol and related compounds

)

Splashes in the eye Flood the eye thoroughly with large quantities of clean, cool water or sterile

liquid from a sealed container and continue for 10–15 min

Ensure that the water bathes the eyeball by gently prising open the eyelids and

keeping them apart until treatment is completed. Do not attempt to remove

anything that is embedded

All eye injuries from chemicals require medical advice. Apply an eye pad and

arrange transport to hospital

Information to accompany the casualty:

Chemical involved

Details of treatment already given

Inhalation of gas Remove the casualty from the danger area after first ensuring your own safety

Loosen clothing; administer oxygen if available

If the casualty is unconscious, place in the recovery position and watch to see

if breathing stops

If breathing has stopped, apply artificial respiration by the mouth-to-mouth

method; if no pulse is detectable, start cardiac compressions

If necessary, arrange transport to hospital

Information to accompany the casualty:

Gas involved

Details of treatment already given

(

Special procedures apply to certain chemicals, e.g. hydrogen cyanide)

Ingestion of poisonous chemical If the chemical has been confined to the mouth, give large quantities of water

as a mouthwash; ensure that the mouthwash is not swallowed

If the chemical has been swallowed, small amounts of water may be administered,

more if the chemical is corrosive; administer a specific antidote if one exists

Do not induce vomiting

Arrange transport to hospital

Information to accompany the casualty:

Chemical swallowed

Details of treatment already given

Estimate of quantity/concentration of chemical consumed

Records

Any injuries or cases of illness treated should be recorded. The minimum details are:

• Date, time and place of incident/treatment.

• Name and job of casualty.

• Details of injury/illness and of treatment.

• Subsequent movements of casualty (i.e. returned to work, sent home, sent to hospital, etc.).

• Name and signature of person providing treatment.

Personal protection

Because personal protection is limited to the user and the equipment must be worn for the

duration of the exposure to the hazard, it should generally be considered as a last line of defence.

Respiratory protection in particular should be restricted to hazardous situations of short duration

(e.g. emergencies, maintenance, or temporary arrangements while engineering control measures

are being introduced). Occasionally, personal protection may be the only practicable measure and

a legal requirement. If it is to be effective, its selection, correct use and condition are of paramount

importance. (Therefore within the UK the Personal Protective Equipment at Work Regulations

1992 require the provision of suitable p.p.e. except where and to the extent that a risk to health

and safety is adequately controlled by other means. This has to be maintained, which covers:

replacement or cleaning and keeping in an efficient state, in efficient working order and in good

repair.)

Respiratory protection

Recommendations for the selection, use and maintenance of respiratory protective equipment are

provided in the UK by BS 4275 1997 and BS EN 132. The two basic principles are:

• purification of the air breathed (respirator) or

• supply of oxygen from uncontaminated sources (breathing apparatus).

If the oxygen content of the contaminated air is deficient (refer to page 72), breathing apparatus

is essential. The degree of protection required is determined by the level of contamination, the

hygiene standard for the contaminant(s), the efficiency of any filter or adsorber available, and the

efficiency with which the facepiece of the device seals to the user’s face (this is reduced by

beards, spectacles etc.). The level of comfort and user acceptability are further considerations.

The nominal protection factor (NPF) describes the level of protection afforded by a specific

respirator:

NPF =

Concentration of contaminant in air

Concentration of contaminant inside facepiece

The British Standard also uses the Assigned Protection Factor, i.e. the level of respiratory protection

that can realistically be expected to be achieved in the workplace by 95% of adequately trained

and supervised workers, using a properly functioning and correctly fitted respiratory protective

device (see Table 13.9)

PERSONAL PROTECTION 433

434 OPERATING PROCEDURES

Table 13.9 Assigned Protection Factors for Respirators and Breathing Apparatus

Type APF (depending upon detailed

equipment specification

1 Filtering devices 4–40

Half or quarter mask and filter

Filtering half-mask without inhalation valves

Valved filtering half masks

Filtering half masks

Full face mask and filter

Power assisted filtering device with full, half or quarter masks

Power filtering device with helmet or hood

2 Breathing apparatus 10–2000

Light duty construction air line

Fresh air hose and compressed air line

Self contained

Gas masks (canister or cartridge mask)

Respirators for gases and vapours comprise a facepiece and a container filled with a specific

adsorbent for the contaminant. Care must be taken to select the correct type. More than one

canister can be attached.

The useful life of a canister should be estimated based on the probable concentration of

contaminant, period of use, breathing rate and capacity of the canister.

Dust and fume masks

Dust and fume masks consist of one or two cartridges containing a suitable filter (e.g. paper or

resin-impregnated wool) to remove particulate contaminant. The efficiency of the filters against

particles of various sizes is quoted in manufacturers’ literature and national standards. Such

masks do not remove vapour from the air.

Facepiece fit is the limiting factor on the degree of protection afforded. Efficiency tends to

increase with use, i.e. as the filter becomes loaded, but the resistance to breathing also increases.

‘Paper cup’ type masks are also available.

Powered dust masks

Masks are available with battery-powered filter packs which supply filtered air to a facepiece

from a haversack filter unit. Another type comprises a protective helmet incorporating an electrically

operated fan and filter unit complete with face vizor and provision for ear muffs.

Breathing apparatus

Compressed airline system: a facepiece or hood is connected to a filter box and hand-operated

regulator valve which is provided with a safety device to prevent accidental complete closure.

Full respiratory, eye and facial protection is provided by full-facepiece versions. The compressed

air is supplied from a compressor through a manifold or from cylinders.

Self-contained breathing apparatus is available in three types:

• Open-circuit compressed air.

• Open-circuit oxygen-cylinder, liquid or solid-state generation.

• Regenerative oxygen.

All respiratory protective systems should be stored in clean, dry conditions but be readily accessible.

They should be inspected and cleaned regularly, with particular attention to facepiece seals, non-

return valves, harnesses etc. Issue on a personal basis is essential for regular use; otherwise the

equipment should be returned to a central position. Records are required of location, date of issue,

estimated duration of use of canisters etc.

Guidance on the choice of respiratory protection for selected environments is given in Figure

13.6. All persons liable to use such protection should be fully trained; this should cover details of

hazards, limitations of apparatus, inspection, proper fitting of facepiece, testing, cleaning etc.

Toxic

Low

toxicity

Environment

Confined spaces e.g. tanks, stills

Allowing unrestricted

movement

Allowing limited

movement

DG G

HAZARDS

All hazards All hazards

CBAABA

APPARATUS

CRHDR HDH CBA PDR PPD GDR

CAR or

CBA

CPF or

CBA

Low

toxicity

Toxic

Low

toxicity

Toxic

Normal working conditions

Allowing unrestricted

movement

DG D G OD D OD

Figure 13.6

Guide to the selection of respiratory protection

Hazards Equipment

D Dust ABA Air line breathing apparatus

G Gas CAR Canister respirator

DG Dust and gas CBA Self-contained breathing apparatus

OD Oxygen deficiency CPF Canister respirators with particulate filters

CR Cartridge respirator

GDR General purpose dust respirators

HDH High efficiency dust respirators

HDR Positive pressure direct dust hoods and blouses (high efficiency)

PDR Positive pressure powered dust respirators

PPD Positive pressure powered dust hood and blouses

Eye protection

The common-sense approach to the use of eye protection, includes:

• Eye protectors and/or fixed shields provided according to the nature of the process.

• Eye protectors on personal issue.

• Replacement of lost, defective or unsuitable eye protectors.

• Eye protectors suitable for individual needs.

• Eye protectors and shields that conform to an appropriate, approved specification and are

marked to indicate intended use.

PERSONAL PROTECTION 435

436 OPERATING PROCEDURES

There are also requirements relating to the proper use and care of eye protectors/shields.

The normal range of personal eye protection is summarized in Table 13.10. In the UK the

appropriate standard is BS EN 167, 168, 175 and BS 7028. Fixed shields can be of polycarbonate

plastic to guard against splashing and projectiles, or of toughened glass or Perspex for protection

against splashing only. Wrap-around of the hazard is required. If the need for access behind a

shield cannot be eliminated personal protection is still necessary.

Table 13.10 Normal range of personal eye protection

Safety spectacles A variety of styles and colours are available with different side-shields to protect

against lateral hazards

Attention must be given to both the lens (available toughened/tinted/to personal

prescription for wearers requiring corrected vision) and the frame

Cup and wide-vision goggles Tend to be more versatile and cheaper and offer more protection and, according

to design, can protect against fine dust, fumes, liquid splashes and impact

from flying particles

Tend to be less comfortable than safety glasses and usually cannot be worn over

ordinary spectacles

Often mist up and as a rule are not fitted with prescription lenses

Face shields Intended to protect from the forehead to the neck

Some are attached to headgear and equipped with a chin-guard to prevent upward

splashing of acids/alkalis

The transparent screen is commonly made of polycarbonate

Heavier special versions are available, e.g. for welding

Head protection

Head protection is required against falling objects but also serves against heat, chemical splashes,

or entanglement of hair in machinery. The appropriate standard is BS EN 397 (1995).

Common-sense guidelines can be deduced from the requirements for ‘building operations’ and

‘works of engineering construction’ summarized in Table 13.11. In special situations, e.g. for fire-

fighting or protection against toxic chemicals, hoods and suits cover the head and neck and many

incorporate protection.

Table 13.11 Head protection requirements for construction activities (Construction (Head protection) Regulations

1989)

Provision, maintenance and replacement whenever necessary

Regular checking/replacement

Protection to be adequate, e.g. to BS EN 397 or equivalent standard (Type 1 helmets with comfort options strongly recommeded)

Protection to be compatible with the work/activity of the wearer

Protection to be worn at all times unless there is no risk from falling objects or possibility of hitting the head against

something

Wearing of safety helmets to be ensured

Hand protection

Protection of the hands may rely upon gloves or barrier creams. The choice of gloves depends

upon:

• Hazard to be protected against, e.g. corrosive or irritant chemicals, heat, abrasion.

• Degree of resistance required.

• Sensitivity required.

• Area to be protected, e.g. to wrist level or extending over the forearms.

For applications where surgical gloves provide adequate protection, if these are of natural

rubber latex then powder-free gloves with low/undetectable protein and allergen levels are advisable.

(Alternatively the use of nitrile gloves eliminates the risk of latex allergy.)

General advice on the suitability and degree of resistance of glove materials are summarized

in Table 13.12. In all cases, however, in addition to the necessary mechanical properties (i.e.

resistance to abrasion, blade cut resistance, tear resistance and puncture resistance rated according

to European Standard EN 388), consideration should be given to the resistance to the specific

chemicals involved.

Chemical permeation is rated in tests under EN 374-3. The breakthrough time of a chemical

through a glove is quoted as a permeation index:

Breakthrough time (min)

Greater than 10 30 60 120 240 480

Permeation index 1 2 3 4 5 6

If the time <10 minutes the index is 0. Clearly the greater the index the better the resistance to

permeation.

Some glove suppliers also provide data on, or a noting of, degradation, i.e. the physical effects

which a chemical will have upon a particular glove material.

Resistance to penetration by micro-organisms is covered by EN 374-2 and protection from low

temperatures in EN 511. Careful handling and regular inspection are essential since chemicals

and abrasion will eventually cause deterioration of gloves. Rinsing in clean water and drying

naturally will prolong their life.

Barrier creams are applied before work to provide a protective film. A different type of cream,

cleansing cream, is applied after work to aid dirt removal and to condition skin with humectant.

Limitations of barrier creams

• They may become a reservoir for harmful chemicals.

• Water-soluble preparations should not be used for aqueous situations; water-repellant creams

are available for such applications.

• There is a limit to the quantity of chemical a barrier cream can repel.

• Effectiveness diminishes as a result of abrasion and massage.

• They are unlikely to prevent an allergic contact dermatitis.

Protective clothing

Protective clothing includes overalls, bibs, duffle coats, aprons, complete one-piece suits with

hoods, spats, armlets etc. It is chosen for protection against mechanical hazards, abrasion,

extremes of temperature etc. as well as chemicals. The nature of the hazard and user comfort

dictate the choice. The properties of a range of protective clothing materials are listed in Table

13.13. Further guidance on selection, use and maintenance of chemical protective clothing is

given in BS 7184:1989.

PERSONAL PROTECTION 437

438 OPERATING PROCEDURES

Table 13.12 Glove material resistance rating (courtesy James North & Sons Ltd)

Glove material

Chemical Natural rubber Neoprene Nitrile Normal PVC High grade PVC

Organic acids

Acetic acid E E E E E

Citric acid E E E E E

Formic acid E E E E E

Lactic acid E E E E E

Lauric acid E E E E E

Maleic acid E E E E E

Oleic acid E E E E E

Oxalic acid E E E E E

Palmitic acid E E E E E

Phenol E E G E E

Propionic acid E E E E E

Stearic acid E E E E E

Tannic acid E E E E E

Inorganic acids

Arsenic acid G G G E E

Carbonic acid G G G E E

Chromic acid (up to 50%) G F F E

(1)

Fluorosilicic acid G G G E G

Hydrochloric acid (up to 40%) G G G E G

Hydrofluoric acid G G G E

(1)

Hydrogen sulphide (acid) F F G E E

Hydrogen peroxide G G G E E

Nitric acid (up to 50%) NR NR NR G

(1)

Perchloric acid F G F E

(1)

Phosphoric acid G G G E G

Sulphuric acid (up to 50%) G G F E

(1)

Sulphurous acid G G G E E

Saturated salt solutions

Ammonium acetate E E E E E

Ammonium carbonate E E E E E

Ammonium lactate E E E E E

Ammonium nitrate E E E E E

Ammonium nitrite E E E E E

Ammonium phosphate E E E E E

Calcium hypochlorite NR G G E E

Ferric chloride E E E E E

Magnesium chloride E E E E E

Mercuric chloride G G G E E

Potassium chromate E E E E E

Potassium cyanide E E E E E

Potassium dichromate E E E E E

Potassium halides E E E E E

Potassium permanganate E E E E E

Sodium carbonate E E E E E

Sodium chloride E E E E E

Sodium hypochlorite NR F F E E

Sodium nitrate E E E E E

Solutions of copper salts G G G E E

Stannous chloride E E E E E

Zinc chloride E E E E E

Alkalis

Ammonium hydroxide E E E E E

Calcium hydroxide E E E E E

Potassium hydroxide E G G E E