Two new standards were recently finalized by California's Occupational Safety and Health Standards Board (OSHSB) that address hazards common to laboratory workers and tree trimmers. Read on to learn what's new.

Microtome safety

Microtomes—also known as "histotomes" or "cryostats"—are commonly found in health care, academic institutions, research facilities, and biological laboratories. These lab devices section extremely thin slices of tissue for microscopy samples by moving a tissue block over a razor-sharp blade.

Microtomes don't typically come equipped with point-of-operation guarding like that required by Cal/OSHA in General Industry Safety Orders (GISO) Section 4184, and aftermarket guards aren't readily available. Accidental cuts to fingers and hands are common when using microtomes, but these injuries are generally minor and not reportable. However, fingertip amputations do sometimes occur.

To address the hazards of microtomes, OSHSB has:

• Added a definition of "microtomes" to Section 3207, where general definitions used in the Cal/OSHA standards are found;


• Added an exception to Section 4184 that exempts microtomes from guarding requirements when guarding is not feasible;and


• Created a new Section 3558, which includes safe work practices and training requirements for microtome operators.

Tree work

After several fatal incidents in which tree workers were suffocated by the palm frond skirts (dead growth under the palm canopy) of the trees they were trimming, Cal/OSHA decided to update its tree trimming requirements.

OSHSB has updated GISO Article 12, Tree Work, Maintenance, or Removal, to address:

• Definitions. Many new definitions are found in Section 3420. In particular, ornamental palms have been added to the standard's scope.


• Training requirements. Section 3421 expands the training and retraining requirements for tree trimmers and requires training in chemical, plant, and animal hazards as well as electrical hazards and emergency response.


• First-aid requirements. Section 3421 now requires that at least two workers trained in first aid and cardiopulmonary resuscitation (CPR) be available during field work involving two or more employees at a work location. New employees must be trained in first aid and CPR within 90 days of their hiring dates.


• Electrical safety measures. Section 3423 has been expanded to detail the training that must be given to tree workers who may be exposed to live electrical equipment or conductors and to specify minimum clearance distances.


• Mobile equipment. Section 3424 has been expanded to cover maintenance, inspection, and safe operation requirements for mobile equipment used in tree work. This section also includes expanded safe work practices for brush chippers.


• Power saws. Section 3425 includes expanded safe work practices for power saw use, including a requirement that tool lanyards be provided for heavier saws.


• Hand tools. Section 3426 includes expanded safe work practices for using hand tools, including a prohibition against carrying tools by hand while climbing and a requirement that workers using hand tools remain a safe distance from one another.


• Climbing equipment. Technical specifications for many different types of tree climbing equipment are now included in Section 3421.


• Safe work procedures. Safe work procedures specified in Section 3427 include inspection requirements for climbing equipment; communication methods to be used between workers at elevation and workers on the ground; the establishment of "drop zones" to protect workers on the ground; the use of rigging in removing trimmed material; and safe work practices for removing dead palm fronds and felling operations.

Practice tip

The CPR and first-aid training requirement does not apply to workers who pick up downed branches after emergencies if those workers don't use tree work equipment such as chain saws and brush chippers.

Section 3428, Operating Rules, has been repealed; most of the information from that section has been incorporated elsewhere in the revised Article 12.

Besides the revisions in Article 12, OSHSB amended the High-Voltage Electrical Safety Orders (HVESO), Section 2950, to delineate the minimum approach distances to energized conductors for persons other than qualified line clearance tree trimmers and trainees.

Cal/OSHA aligns standards with federal OSHA

Two additional revisions took effect in October: revisions to the first-aid standards for electrical workers and some minor technical corrections to a handful of other standards.

First aid for electrical workers. In October 2011, OSHSB adopted federal OSHA's revisions to the requirements for first-aid training and availability for electrical workers. These revisions were added to the Low-Voltage and High-Voltage Electrical Safety Orders. OSHSB also applied these revisions to electrical workers in construction and general industry.

It later came to OSHSB's attention that the federal standard specifically excludes construction, meaning the agency had overreached its authority in applying the new standard to construction. The October 2012 revision corrects that mistake, clarifying the standard's applicability and bringing it into line with the federal standard.

The effect of this change, according to OSHSB, will be to return requirements for first-aid and medical services for construction work to those that applied before October 27, 2011. The change took effect on October 5, 2012.

Technical corrections. On December 27, 2011, federal OSHA published typographical corrections and nonsubstantive technical amendments to 16 standards, effective October 4, 2012. OSHSB identified four of those amendments that applied to California's standards.

Two were typographical corrections (correcting the CAS number for oleum in GISO Section 5189 and correcting a cross-reference in GISO Section 5192, Hazardous Waste Operations and Emergency Response). Two other corrections pertain to California's GISO and Construction Safety Orders lead standards and affect existing employer action thresholds for employee notification of lead exposure and temporary medical removal with medical removal protection benefits.