cannot be overexposed to laser radiation if there is an effective laser safety program in place!!!

Transcription

1 Education, Training & Standards In other words, workers cannot be overexposed to laser radiation if there is an effective laser safety program in place!!!

2 Education, Training & Standards The employer should establish & maintain an adequate program for the control of laser hazards to the eyes & skin

3 Education, Training & Standards Class 2 & 3a lasers & laser systems... A laser safety program meeting the requirements of ANSI Standard Z or a program providing an equivalent level of worker protection, constitutes an effective exposure control plan.

4 Education, Training & Standards Class 3b & 4 lasers & laser systems A laser safety program meeting the requirements of ANSI Standard Z constitutes an effective exposure control plan.

5 Education, Training & Standards The requirements of a laser safety program are summarized in Section 1.3 of ANSI Standard Z

6 Education, Training & Standards

7 ANSI standards require laser facilities regardless of their size to establish & maintain an adequate safety program for the control of laser hazards. Laser Safety Program

8 Laser Safety Program The employer has the fundamental responsibility for assurance of the safe use of lasers owned &/or operated by the employer or employee.

9 Laser Safety Program The DM must designate a Laser Safety Officer (LSO) for the facility: to be responsible for implementing a laser safety program for all circumstances involving human access to Class 3b &/or Class 4 laser radiation.

10 Laser Safety Program A laser safety officer (LSO) is responsible for: Establishing the laser treatment controlled area & ensuring only authorized personnel occupy the operating area.

11 Laser Safety Program A LSO is responsible for: Evaluating hazards in laser treatment areas... e.g. floor cluttered, unclear access to footswitch, cables not secure, cords crimped, etc.)

12 Laser Safety Program A LSO is responsible for: Approving installation & equipment prior to use, & modifications to existing equipment & facilities Approving standard operating procedures (SOPs), administrative & procedural controls (i.e. checklists)

13 Laser Safety Program A LSO is responsible for: Recommending or approving protective equipment (i.e. eyewear, clothing, barriers, assuring personnel safety, etc. as required)

14 Laser Safety Program Auditing the functionality of control measures periodically to ensure proper operation. Approving wording on area signs & equipment labels

15 Laser Safety Program Keeping a laser use log that records laser procedure & time, power settings, accessories used, & problems encountered & their resolution.

16 Laser Safety Program Keeping a laser maintenance log Assuring adequate safety education & training are provided to all laser area personnel.

17 Laser Safety Program The DM may be the laser safety officer In all cases a laser safety officer (LSO) must be designated & must have authority to carry out a laser safety program in the facility.

18 Laser Safety Program The LSO must have training & experience to administer a laser safety program. The LSO must be authorized by the employer & be responsible for monitoring & overseeing the control of laser hazards.

19 Safety Zones Laser safety standards make use of the concept of maximum permissible exposure (MPE)...

20 Safety Zones Maximum permissible exposure (MPE) the amount of energy (joules) or power (watts) in the cross section of area (cm 2 ) of a laser beam......that a person may be exposed without hazardous effect or adverse biological changes in the eye or skin.

21 Safety Zones Laser safety standards use maximum permissible exposure (MPE), to protect a person from laser exposure.

22 Safety Zones Laser radiation exposure can be unsafe within a specific distance, beyond which it is not harmful......as the laser beam spreads out (divergence) & attenuates or is scattered by air...

23 Safety Zones...consequently, knowledge of this distance can be used to protect oneself and others from laser exposure injury

24 Safety Zones The distance beyond which it is safe to view or be exposed to a laser beam is unique for each type of laser & depends on many factors. Standards define the area inside this distance as the Nominal Hazard Zone (NHZ)

25 Safety Zones Nominal Ocular Hazard Distance (NOHD) The distance along the axis of an unobstructed beam to the human eye beyond which the irradiance or radiant exposure, during installation or service, is not expected to exceed the appropriate MPE.

26 Safety Zones It is simple to define an area or zone where the laser is used & exposures in this area exceeds the maximum permissible exposure......& to require safety precautions be used in this zone.

27 Safety Zones Designate the laser operating &/or treatment room as the NHZ Prevent inadvertent scattered beam from exiting the room through open doors, windows or other breaks in the treatment room enclosure!

28 Safety Zones Access into the treatment enclosure must be restricted to essential personnel during treatments

29 Safety Zones

30 Safety Zones Occupancy & activity within the laser treatment controlled area are subject to supervision to protection against laser hazard use. The laser treatment area is usually a separate room with a closeable door & covered windows.

31 Safety Zones Appropriate warning signs MUST be identified at all entrances to the area.

32 Safety Zones The entry warning sign(s) can be a large version of the laser warning sign that is attached to the laser

33 Safety Zones A sign with an exclamation mark in the triangle is the newer ANSI standard recommended sign & is the style required when interpreting the requirement of the WorkSafeBC, Occupational Health & Safety Regulation. The older style is still acceptable!

34 Safety Zones

35 Safety Zones Additional wording recommended for ANSI entrance signs are: Eye Protection is Required Laser Protective Eyewear Required Invisible Laser Radiation Knock Before Entering Restricted Area

36 Safety Zones Some infrared radiation can travel through window glass & other openings & be reflected off mirrors or other shiny surfaces.

37 Safety Zones Cover windows with a non flammable opaque material labeled with the optical density OD number or restrict radiation from leaving the treatment room.

38 Safety Zones Fire proof light weight laser blocking covers are available with magnetic sides to put on & off easily. Only trained &/or authorized persons with protective equipment are allowed to enter or be in the treatment room!

39 Safety Zones Reflective items must not be used or worn in the area. Access to the laser treatment area must be restricted, but not prohibit rapid entry & exit in an emergency.

40 Standard Operating Procedures Safety policies & procedures need to be established & copies posted. Including... authorizations for laser use, operating instructions, prior-to-use checklists, maintenance/service instructions.

41 Standard Operating Procedures Newer lasers often have sophisticated built-in safety features: protective housings around laser, interlocks on the protective housings a key control & warning systems. To prevent unauthorized operations securely store laser &/or require a key or coded access to enable the laser.

42 Standard Operating Procedures Safety Features The guarded switch controlling client exposure, must be guarded to prevent inadvertent activation. or......require two simultaneous actions, such as foot pedal depression & hand trigger to operate laser.

43 Standard Operating Procedures Safety Features Emergency shutoff switch must be available to operator or assistant for rapid shutdown. Equipment must be serviced & maintained as recommended by manufacturer... to ensure safeguards remain functional.

44 The laser operator must periodically check: Standard Operating Procedures Safety Features! Electrical cords for damage...! Skin coolant hoses for wear & damage! Testing by protected staff

45 Non-Beam Hazards Airborne contaminants Laser tissue interactions produce a plume of smoke that may contain bacterial & viral particles (0.1 to 0.3 um)

46 Non-Beam Hazards Airborne contaminants Hazardous chemicals (e.g. benzene, formaldehyde, phenol and toluene); some of which are carcinogens.

47 Non-Beam Hazards Airborne contaminants To avoid the inhalation of aerosols, appropriate air evacuation systems must be used! The system is determined by the laser beam power (i.e. irradiance W/cm 2 )

48 Non-Beam Hazards Protecting operator & surgical staff Controlling dispersion of laser exhaust hazardous materials, potentially toxic gases & airborne contaminants Capture exhaust 2-5 cm at point of production i.e. treatment area. Completely trap or vented out of the area in an environmentally sound manner.

49 Non-Beam Hazards Protecting operator & surgical staff Portable smoke extractors using charcoal &/or HEPA filters are satisfactory (see Control of Smoke From Laser/Electric Surgical Procedures)... National Institute for Occupational Safety and Health (NIOSH)

50 Non-Beam Hazards Protecting operator & surgical staff Filters & absorbers in portable smoke evacuators require replacing regularly Local exhaust ventilation techniques serve as the first line of protection from exposure. ANSI Z , section

51 Non-Beam Hazards Protecting operator & surgical staff ANSI Z , section Respiratory Protection: At present there is no suitable halfmask respirator (fitting over nose & mouth) used for the specific purpose of excluding all laser generated plume particulates, bacteria, viruses, gases, vapors, or other irritants...

52 Non-Beam Hazards Protecting operator & surgical staff Surgical masks are intended to protect the patient from the contaminated nasal or oral droplets of anyone with access to the surgical field.

53 Non-Beam Hazards Protecting operator & surgical staff Standard surgical masks do not offer protection against particles of 0.2 um or smaller. Filter masks that filter > 0.2 um particles & rated for laser use are available,...such as the half face mask with an organic cartridge and HEPA filter pad (P100).

54 Non-Beam Hazards Fire Safety Lasers should not be used in the presence of: flammable anesthetics prep solutions containing alcohol drying agents petroleum ointments flammable plastics

55 Non-Beam Hazards Fire Safety Recommendations: 1. Surgical drapes made of flameretardant material & protected with moistened towels & sponges near the primary laser beam. 2. Water & fire extinguisher should be readily available.

56 Non-Beam Hazards Fire Safety 3. Adequate prep towels & the insertion of a moistened sponge in the anal opening to reduce the release of methane gas when performing surgery in the perineal area. 4. Use intravenous anesthetic technique instead of a volatile gas anesthetic when practicable.

57 Non-Beam Hazards Fire Safety 5. An oxygen rich environment - may increase the risk of fire hazard. Use laser safe endotracheal tubes that may include nonflammable metal tubes, specially wrapped red rubber tubes, or 100% silicone tubes.

58 Non-Beam Hazards Fire Safety The cuff of the endotracheal tube should be filled with saline. Protect the endotracheal tube with moistened sponges.

59 Non-Beam Hazards Electrical Hazards Ensure there is adequate amperage, voltage & avoid fluids, which may result in a short circuit, to the laser system. Proper grounding & insulation are Imperative.

60 Non-Beam Hazards Internal maintenance must only be performed by a qualified biomedical technician for the specific type of laser.

61 Non-Beam Hazards Documentation & Records The DM must keep records & have them available on site. Records include: Laser operator qualifications i.e. laser educational & safety training Standard Operating Procedures (SOP) Safety checklist (see Appendix 1) Previous safety inspections Reports of accidents or incidents All records must be typed or legibly written in and retained.

62 Non-Beam Hazards Conclusion Surgical lasers are powerful & potentially dangerous instruments Misuse can result in severe injury to the animal, occupationally exposed veterinarian & staff.

63 Non-Beam Hazards Conclusion Protection is relatively easy With safety & training the potentially exposed veterinarian & staff can ensure their protection & that of the animal.

64 References: Non-Beam Hazards Lasers Have You Seen the Light? by Timothy Holt, DVM Proceedings & Note Book, CANWEST Veterinary Conference, 2005.

65 Non-Beam Hazards References: Further information on laser safety may be obtained from: The Laser Institute of America Research Parkway, Suite 125 Orlando FL Phone: Rockwell Laser Industries Inc PO Box Cincinnati OH Phone: toll free

66 References: Non-Beam Hazards Radiation Protection Services BC Centre for Disease Control th Ave W Vancouver BC V5Z 4R4 Phone: American National Standards Institute (ANSI) 1819 L Street, NW, 6th Floor Washington DC Phone:

67 Non-Beam Hazards Glossary of Terms ANSI: American National Standards Institute - a private, non-profit organization that administers the US voluntary standardization and conformity assessment system. Incidental personnel: those whose work makes it possible, but unlikely, that they will be exposed to laser energy sufficient to damage their skin or eyes.

68 Non-Beam Hazards Glossary of Terms Infrared: invisible radiation with wavelengths from approximately 700 nanometers (nm) to 1 millimeter. Irradiance: the power per unit area, usually expressed in watts per square meter, used to measure or quantify the intensity of laser radiation. Joule: the unit of energy used to measure the energy of a laser pulse.

69 Non-Beam Hazards Glossary of Terms Laser controlled area: area that is appropriately enclosed so that no laser radiation above the maximum permissible exposure inadvertently escapes to injure unsuspecting persons. Laser personnel: those who work routinely in the laser environment & must be fully protected.

70 Non-Beam Hazards Glossary of Terms Laser Safety Officer: the person with training & Designated Member experience who is authorized by the to be responsible for the laser safety program in the facility. MPE: abbreviation for the Maximum Permissible Exposure allowed by the laser standard before injury occurs to the skin or eyes.

71 Non-Beam Hazards Glossary of Terms Nd:YAG: notation for the component in a laser that produces infrared radiation i.e. Nd:YAG (neodymium-doped yttrium aluminum garnet; Nd:Y 3 Al 5 O 12 ) a crystal used as a lasing medium for solid-state lasers.

72 Non-Beam Hazards Glossary of Terms NHZ - Nominal Hazard Zone: The space within which the level of the direct, reflected, or scattered radiation during normal operation EXCEEDS the maximum permissible exposure. Exposure levels beyond the boundary of the NHZ are below the MPE

73 Non-Beam Hazards NOHD Nominal Ocular Hazard Distance The distance along the axis of the unobstructed beam from a laser, fiber end, or connector to a human eye, beyond which the irradiance or radiant exposure, is not expected to exceed the applicable Maximum Permissible Exposure.

74 Non-Beam Hazards Optical Density [OD] a measure of the laser radiation permitted to pass though a filter (OD = log10 (potential eye exposure/mpe) Optical Density 0 = light transmission 1 Optical Density 1 = light transmission 0.1 Optical Density 2 = light transmission 0.01 Optical Density 3 = light transmission Optical Density 4 = light transmission Optical Density 5 = light transmission etc.

75 Non-Beam Hazards Optical density - a measure of laser radiation permitted to pass though a filter Which transmits more light an Optical Density OD of 1 or an OD of 5? Optical Density 1 = light transmission 0.1 Optical Density 5 = light transmission Protection is rated by the Optical Density (OD) of safety glasses, which measures how much laser light is blocked.

76 Appendix 1: Laser Safety Checklist Procedure Correct wavelength of goggles? Laser safety goggle wavelength blocks laser wavelength in use? Laser treatment area clear of reflective items; e.g. reflective surfaces, mirrors, steal sinks, taps, glass, etc? Patient s eyes, skin, etc. protected? Record OD of protective goggles. (OD = log 10 (laser beam power /MPE) Warning sign outside laser door? Warning notices posted? Laser &/or electrosurgical smoke masks available? Operator s Initials

77 Appendix 1: Laser Safety Checklist Procedure Use of laser protective clothing, gloves, etc.? Anesthetic machine inspected? Emergency shutdown procedure posted? Laser treatment area clear of unauthorized personnel? MPE - Maximum Permissible Exposure AREA clearly defined? Record average power of laser. Record laser classification used. Record name of laser operator. Operator s Initials

78 Appendix 1: Laser Safety Checklist Procedure Smoke evacuation working? Fire extinguisher/water available? Presence of laser safety official? Preventative maintenance of laser up to date? Name of person holding safety key? Permanent location of safety key? Name of emergency contact? Laser designated as controlled area? Operator s laser manual available? Contact information of manufacturer? Operator s Initials