Country: Angola Date: Dec. 12th - 2011

Lost Time Injury ( LTI): Chemical Burns to the eyes Number of pages: 01

IP (Injured Person) started his shift at 07:30 a.m. and around 12:30 p.m. on December 12, IP (Maintenance Plumber) was preparing some Caustic Soda (Lye) to execute his duties. IP mixed some Sodium Hydroxide (NaOH) also known as Caustic Soda (or Lye) with cold water, resulting in a strong and highly exothermic reaction. The mixture rose to the eyes, causing burns. IP was treated washing the eyes thoroughly and area around them with clean and fresh water. After that the IP was sent to the clinic. The IP stayed home for 7 days for treatment. FINDINGS The safety glasses were not used properly, IP had removed them to the top of the head claiming that it was very dark and the goggles weren’t allowing him to see. IP was not use the recommended product for that purpose. PREVENTIVE / CORRECTIVE ACTIONS The preparation of the Caustic Soda must be handled with caution. The mixture must be done using warm water, because the reaction will be weaker. Also, always wear the safety glasses adequately, as well, as all the proper PPE, and do the mix in a well lit and ventilated area. In Angola, due to the risks involving the use of Caustic Soda, we must replace it with the HDB 90 (product from Mitam) for biological treatment of septic tanks and pipes. KEY LESSONS LEARNED & RECOMMENDATIONS Sodium hydroxide (NaOH), also known as lye and caustic soda, is a caustic metallic base. It is very soluble in water and is highly exothermic when you dissolve it in cold water.

Na2O + H2O → 2 NaOH Sodium hydroxide is used in the home as a drain cleaning agent for clearing clogged drains, usually in the form of a dry crystal or as a thick liquid gel. Sodium hydroxide saponifies the triglycerides found in fat into water soluble fatty acid salts. Likewise, sodium hydroxide hydrolyzes the amide bonds in protein, such as those found in hair. These reactions are sped by the heat generated when sodium hydroxide and the other chemical components of the cleaner dissolve in water. Such drain cleaners and their acidic versions are highly caustic and should be handled with care. Solid sodium hydroxide or solutions of sodium hydroxide may cause chemical burns, permanent injury or scarring if it contacts unprotected human, or other animal, tissue. It may cause blindness if it contacts the eye. Protective equipment such as rubber gloves, safety clothing and eye protection should always be used when handling the material or its solutions. Caustic Soda should be replaced by HDB 90 – highly recommended

Solid sodium hydroxide and solutions of more than 2% by weight

(0.5 M) should be labeled as corrosive.

Chemical burn caused by exposure to

a less than 10% sodium hydroxide solution photographed 44 hours after

exposure.

Do you need to report an incident, accident or a near miss?

Please forward your information to João Beato on the following contact details as soon as possible after the incident

Unproper use of safety glasses and mixture done inside.

Proper use of PPE and mixture prepared outside, in a well lit and ventilated area.