Everyone entering a hazardous site must be safe from hazards. The main motive behind the usage of Personal Protective Equipment, commonly known by the acronym PPE, is to offer a barrier for the isolation of individuals from the physical, chemical, and biological hazards that are offered by a hazardous site.
All the organs of the body can be protected by carefully selecting appropriate Personal Protective Equipment. This chapter introduces various types of PPE and describes their usages in different situations. However, the term PPE, in general, refers to Personal Protective Equipment as well as Personal Protective Clothing collectively.
All occupational sites must adhere to an established PPE program. The following should be the primary objectives of the PPE program −
The following should be included in the comprehensive PPE program −
The copies of the written PPE program must be made available for each and every employee working in the organisation. Moreover, each worksite should also possess a reference copy of the PPE program. The technical data on the following must also be made available to the employees −
The PPE Program must be subjected to a review at least once in a year. The following factors must be considered in the review −
A survey covering each site for ensuring the proper enforcement of the regulations regarding the PPE.
A record of the time for which the workers wear various PPE in terms of personhours.
Experiences of illnesses and accidents.
Equipment selection adequacy.
Operational guidelines’ adequacy.
The proper implementation of cleaning, decontamination, inspection, maintenance, and storage programs.
The effectiveness of training programs.
Coordination with Health and Safety programs.
The completion rate of objectives.
Program records adequacy.
Recommendations for the improvement and modification of the program.
Cost of the program.
The outcomes of the evaluation of the program must be made available to the employees as well as the top management for the adaption and the implementation of the program.
Inhalation is one of the major routes for contaminants to enter the body, respiratory protection is very important in hazardous environments. Respiratory protective devicesare also known as respirators and are made up of a facepiece that is attached to an airsource or an air purifier.
The respirators having an air source are called atmosphere-supplying respirators and come in the following two types −
Self-Contained Breathing Apparatus (SCBA) − The air supply source is carried by the user.
Supplied Air Respirator (SAR) − The air supply is located at a remote location and the air is transmitted by a hose.
On the other hand, air purifying respirators have an air purifying element that purifies the surrounding air. These respirators are further distinguished according to the type of airflow used to supply air to the facepiece.
In our subsequent section, we will discuss the different types of respirators distinguished according to the type of airflow.
A positive pressure respirator continues to maintain a constant positive pressure in the facepiece while inhaling as well as exhaling. The following are the two main types of positive pressure respirators −
Where the mask’s positive pressure is maintained (except when the breathing rate is too high) by an exhalation valve and a regulator. In the case of any leakage, the regulator sends a continuous stream of air preventing any contaminants from getting in through the leak.
Where a stream of air is continuously fed to the facepiece. In the case of SAR variants of these respirators, the intrusion of ambient air is checked by the continuous flow of air while rapidly using air supply on the other hand.
A negative pressure is created due to inhalation, which draws air into the facepiece in negative pressure respirators. The most dangerous flaw in negative pressure respirators is that, if any leaks or cracks occur in any part of the respirator, the user inhales contaminated air.
Respirators can further be differentiated depending on the type of facepiece being used in conjunction with the air source. Generally, facepieces come in two different configurations −
Full-facepiece masks encompass the entirety of the face starting from the hairline to the chin. Good eye-protection is provided by them.
Half-facepiece masks only cover the area under the nose and above the chin. No eye-protection is provided in these facepieces.
SCBAs generally have a facepiece attached to a regulator to an air source by a hose. The wearer of this respirator carries the air source. In atmospheres that are immediately dangerous to life and health (IDLH), only positive pressure SCBAs are recommended.
Most of the contaminants can be checked by SCBAs. However, the limited supply of air in the case of SCBAs limit them from continuous prolonged usage, depending upon the rate of consumption of the user and the amount of air carried by him. The heft and the bulk of these respirators hinder the movement of the wearer in confined spaces and may even cause heat stress.
Supplied air respirators provide purified air and never pure oxygen. These respirators supply air from a stationary source. Both positive and negative pressure variants of these respirators are available. The highest level of protection in SARs is provided by positive demand SARs having escape provisions and they are the only SARs recommended in hazardous sites.
In the case of an IDHL atmosphere, a SAR is never recommended unless an escape SCBA is equipped with the SAR. The following two types of air sources are used by SARs −
Although SARs can be used for a significantly longer period as compared to SCBAs, the hose connected to a stationary source of air hinders the wearers from going further distances.
A combination respirator provides the best advantages of an SCBA and a SAR. A regulator is used in the case of these regulators to switch between the SCBA and the SAR modes of its operation. This switching can be either achieved manually or automatically.
A self-contained air supply in these respirator enables its wearer to enter into and exit out of an area, while the connected airline enables its wearer to work for a prolonged period of time at a single stretch.
An air purifying element along with a facepiece constitutes an air purifying respirator. The air purifying element might either be a removable component of the facepiece itself or maybe a separate device connected to the facepiece via a corrugated hose. Different air purifying respirators purify the ambient air by different approaches such as −
However, these respirators find their place in the areas having lower concentrations of contaminants and these respirators are absolutely not recommended for IDHL atmospheric conditions.
Any item that provides skin/body protection is considered personal protective clothing. Some of these may include
Protective clothing serve a purpose. Not all types of protective clothing can help against chemical exposures. In conjunction with the protective clothing, there are certain tools and accessories that must be carried by certain personnel. Some of these accessories are −
The personal protective clothing items have been briefly described below −
An encapsulating suit encapsulates the whole body of the wearer. Gloves and boots may or may not be attached to these suits. These suits protect against chemical exposures, dust, splashes and vapours.
However, due to the lack of proper airline, an immense amount of heat stress may develop with the one who is wearing it. It is highly recommended to use this suit with a cooling suit when used with a closed circuit SCBA.
A non-encapsulating suit is usually an assembly of separate pieces of protective clothing such as jackets, hoods, and pants. Just like an encapsulating suit, this suit protects against particles, splashes and other contaminants. However, it cannot protect against vapours and gasses. Moreover, it does not offer any head or neck protection.
It may also contribute to the build-up of heat. It is strongly recommended to tape-seal junctions near the wrists and the ankles while wearing this suit.
These items are commonly worn along with non-encapsulating suits. These clothing items offer an additional level of protection from splashes, dust particles, and chemicals.
A firefighter’s protective clothing comprises of fireproof gloves, helmets, bunker coats/ running coats, bunker pants/running pants, and running boots. This suit protects the firefighters against fires, heat, minor explosions, hot water, and certain particles.
However, this attire does not help much in preventing risks from gases and chemicals. Moreover, it is too difficult to decontaminate this suit.
Proximity garments, also known as approach garments, are a set of protective clothing. The set comprises boot covers, as well as gloves and hoods made of aluminised nylon. These garments provide an extra layer of protection over other full body suits discussed above.
These garments protect against heat, but not against chemical exposure. However, these garments can be custom made to protect against certain chemicals. It is highly recommended to use auxiliary cooling and SCBA with these garments.
A blast suit consists of blast vests, bomb blankets, and bomb carriers. The suit provides a certain level of protection against minor blasts and detonations. Bomb blankets can also be used to redirect a blast. However, hearing protection is something that is not offered by a blast suit.
A radiation protective suit is a combination of various types of antiradiation clothing items that provide protection against alpha and beta radiations but fail to protect against gamma radiation.
A cooling garment dissipates the excess heat from the body of the personnel wearing other full body suits. Cooling garments significantly reduce the risk of a heat stress emergency. Consider the following approaches while implementing cooling garments −
Cool and dry air is circulated throughout the suit by a pump that uses refrigeration coils, vortex coolers, or heat exchangers for the transmission of air.
Packets of ice are inserted into a jacket.
A pump throughout the body of the wearer circulates water from a reservoir.
A safety helmet is often made from hard plastic, rubber, or a combination of both. It protects the head of its wearer against accidents, projectiles, blasts, blows, and many other head injuries. In addition, the inner lining of the helmet protects the wearer from cold.
A hood protects its wearer against splashes of chemicals, particles, and rain. It is often worn along with a helmet.
A face shield protects the face from the top to the chin. Proper sizes of face shields must be provided for the best fit and the best level of safety. However, they are not capable of protecting the face against projectiles.
These eye-gears protect the eyes against chemical splashes and dust particles that might potentially get into the eye. However, they cannot stop larger projectiles. They also help in protecting the eyes against lasers and bright lights.
Sweatbands absorb the sweat dripping from the head and stop the sweat from entering into the eyes.
Earplugs must be worn in sites having a very high level of noise. This equipment prevents the noise from entering into the ears.
Gloves and sleeves offer a great deal of protection to the hands and the arms of the wearer while handling chemicals and other hazardous substances.
Safety boots usually provide a great deal of protection from chemicals and other such contaminants. Furthermore, they are reinforced with steel for additional protection from physical inflexions.
Knives come in handy in a multitude of scenarios. From cutting a rope to cutting a fatally suffocating suit, a knife has it all covered.
These hand-held light sources are essential for approaching dark environments, confined spaces, and buildings. Moreover, they can also be used as an SOS signal during an emergency.
A dosimeter is used to measure the ionising radiation of a certain surrounding. It is highly recommended to couple a dosimeter with a full body suit.
A locator beacon helps the emergency personnel in locating any injured or contaminated personnel needing help. These beacons use radio waves, sound, or light to transmit the signal.
A two-way radio can be used to communicate with remotely located personnel. These radios use radio waves to transmit voice signals.
A safety harness is a mandatory equipment that must be worn by the personnel who work at greater heights. It significantly diminishes the risk of an emergency due to a fall.