PPE

Protection of Emergency Personnel from Chemical Hazards in Mountainous Areas

Issue 12 and Volume 17.

Patrice Poisson

The Pyrenees-Atlantiques Fire Department (PAFD) protects people, property, and the environment in the most southwest region of France. The region covers an area of 3,000 square miles with a population of 650,000. The department comprises 600 paid firefighters, 2,000 volunteer firefighters, and 150 administrators.

The PAFD has a hazmat team to deal with industrial accidents at chemical plants; accidents related to the transport of hazardous materials; pollution of rivers or water from oil spills and other contaminants; radiological emergencies; and chemical, biological, radiological, nuclear, and explosive (CBRNE) threats. The unit consists of 160 specialists in chemical hazards and 40 specialists in radiological hazards.

In June 2007, a truck overturned while negotiating a curve on a major road between France and Spain. Much of its cargo of potassium hydroxide (17,000 liters) flowed into a river in a ravine more than 55 yards below the roadway, causing significant pollution.

During the reconnaissance and initial technical operations, firefighters specializing in chemical hazards and in mountain search and rescue were ordered to measure the acidity of the land lying between the truck and the river. A member of the rescue team was lowered into the ravine using rappelling equipment to conduct the survey. His protection consisted of only chemical gloves and goggles because a safety harness could not be used in conjunction with the available personal protective equipment (PPE).

On the night of the accident, pH values of 12 were measured in the river from the accident site to just over one mile downstream of the accident. For the first three miles, there was total mortality of fish fauna. The environmental cost of this accident was estimated at $330,000 United States dollars.

A review of this operation highlighted inadequate PPE for the personnel involved. As this type of accident could occur again at any time, the PAFD hazmat team’s chief decided to develop PPE that optimizes team safety in operations involving chemical contamination.

Priority One

Our first priority was to determine if an existing PPE would fulfill our requirements. After inquiring with manufacturers of chemical PPE suits including Draeger, Trelleborg, Respirex, and MATISEC, we found that there was no PPE available with integrated safety harnesses. It became apparent that we would have to create a unique chemical protective suit that would incorporate already proven protective designs for the integrity of both the suit and the safety harness.

We chose French company MATISEC to develop this new PPE. Our hazmat team was already equipped with MATISEC Corporation gas-tight chemical protective suits for emergency teams, the GR III, with inside self-contained breathing apparatus (SCBA). These suits have been completely satisfactory. We also made our choice of Matisec based on a successful relationship with its research and development department. The department needed to create a gas-tight suit with an integrated safety harness that conformed with the requirements of European standards EN 943-1 and EN 943-2 from the existing GR III (PPE level A).

The challenge was to install a safety harness on the hazmat specialist in accordance with the requirements of the mountain search and rescue team without compromising the integrity of the SCBA, ensure adequate comfort during working conditions, and maintain the functionality of both the PPE and the safety harness under working conditions.

(1) To preserve the integrity of the harness, which might be compromised by corrosive chemicals, the PAFD decided that the harness would be positioned inside the suit. This internal positioning required it to consider the lowering device and the connecting line that acts as an umbilical cord connecting the wearer to the lowering device. The placement of the harness in the suit had to allow tight vertical positioning of 45 degrees to the ventral attachment point without irritating the skin of the suit. (Photo by author.)

Suit Design

The fall arrest harness, NAVAHO® BOD by PETZL Corporation, was used in designing the harness to be used in our PPE. To preserve the integrity of the harness, which might be compromised by corrosive chemicals, we decided that the harness would be positioned inside the suit. This internal positioning required us to consider the lowering device and the connecting line that acts as an umbilical cord connecting the wearer to the lowering device. The placement of the harness in the suit had to allow tight vertical positioning of 45 degrees to the ventral attachment point without irritating the skin of the suit.

Another consideration was the choice of breathing apparatus and its positioning. The wearer’s respiratory protection should be ensured by means of a device that would allow at least 45 minutes of breathing. Additionally, the breathing apparatus should minimally affect the positioning of the center of gravity of the carrier during a maximum inclination of 45 degrees from vertical. We decided to use the Triplair breathing apparatus MATISEC also used in spacesuits. This device consists of three bottles of 0.8 gallons under a pressure of 4,350 psi. Everything is protected in a housing made of ABS antishock plastic. This device has been developed for the French Navy. Its small footprint allows for movement in tight areas.

Finally, we decided to equip the suit with the ability to allow breathing of atmospheric air to conserve the capacity of the breathing apparatus bottles during waiting phases before engagement, descent, ascent, and decontamination.

Performance Requirements

The performance requirements for gas-tight chemical protective suits (type 1) are defined in European standard EN 943-1. They are specified in EN 943-2 for equipment for emergency rescue teams. In these documents, resistance to abrasion, flex cracking, bending at -22°F, tear, tensile strength, puncture, and resistance to ignition are taken into account. The sealing conditions must prevent a loss of no greater than 0.04 psi for six minutes at rest. In use, the loss of pressure inside of the suit must not exceed 0.06 psi.

Development and Testing

Following the hazmat team’s needs definition, the MATISEC Corporation made a prototype. Several difficulties were encountered during initial testing:

1. During suspension, the wearer became horizontal because of binding of the umbilical cord attached to the front of the suit.

2. Excessive tensioning of the textile was likely to cause tearing of the umbilical cord. The length of the strap was too long. The strap has been shortened, and the length of the textile has been increased.

3. In a test for attaching to a helicopter winching device, the carabiner rigging would detach from the winching hook.

These issues were quickly resolved.

Another testing phase was to determine if the physical properties of the suit could be maintained regardless of the wearer during a short vertical drop (maintenance of suit vacuum, carabiner function, and radio contact with the mountain specialists).

Operational validation of the suit was the last phase. It consisted of a simulated transportation accident involving hazmat with recovery of barrels of toxic chemicals in a river 30 meters below unattainable. A total of six specialists were engaged as if under real conditions. To determine the physiological effects under these conditions, the medical department monitored the following criteria: heart rate, blood pressure, and temperature.

One of the questions asked was who could respond in this situation. Three categories of specialists were compared: divers accustomed to work with respiratory equipment, mountaineers accustomed to working with ropes, and specialists in chemical risks. The conclusion was that the ergonomics of the suit and breathing apparatus did not cause specific constraints and there was no significant difference between the groups studied.

Standard Equipment

The GR III hazardous environment suit is now part of the regular equipment for the Pyrenees-Atlantiques chemical hazards team vehicles. The suits enable the hazmat team to work under optimum safety conditions.

PATRICE POISSON is a 23-year French career firefighter. He is a deputy chief and a hazardous materials and CBRN specialist.